Signal chain++

This reverts commit 79dab822fd.

.gitmodules

@@ -1,22 +1,9 @@
+[submodule "External/ReactiveCocoa"]
+	path = External/ReactiveCocoa
+	url = https://github.com/ReactiveCocoa/ReactiveCocoa.git
+[submodule "External/Mantle"]
+	path = External/Mantle
+	url = https://github.com/github/Mantle.git
 [submodule "External/OHHTTPStubs"]
 	path = External/OHHTTPStubs
 	url = https://github.com/github/OHHTTPStubs
-[submodule "Carthage.checkout/Nimble"]
-	path = Carthage/Checkouts/Nimble
-	url = https://github.com/Quick/Nimble.git
-[submodule "Carthage.checkout/ReactiveCocoa"]
-	path = Carthage/Checkouts/ReactiveCocoa
-	url = https://github.com/ReactiveCocoa/ReactiveCocoa.git
-[submodule "Carthage.checkout/Quick"]
-	path = Carthage/Checkouts/Quick
-	url = https://github.com/Quick/Quick.git
-[submodule "Carthage.checkout/xcconfigs"]
-	path = Carthage/Checkouts/xcconfigs
-	url = https://github.com/jspahrsummers/xcconfigs.git
-[submodule "Carthage.checkout/Mantle"]
-	path = Carthage/Checkouts/Mantle
-	url = https://github.com/Mantle/Mantle.git
-[submodule "Carthage/Checkouts/Nimble"]
-	url = https://github.com/Quick/Nimble.git
-[submodule "Carthage/Checkouts/Quick"]
-	url = https://github.com/Quick/Quick.git

.travis.yml

@@ -1,10 +0,0 @@
-osx_image: xcode8.3
-language: objective-c
-
-install: script/bootstrap
-script: script/cibuild
-notifications:
-  email: false
-env:
-  global:
-    secure: L4C3hHzXc/sgL35dIz3kjqIzPWnXCHsFOgbOcz0f249zlnegeKHQdChm4HUDtfrbmKLMYQCIvVfcgPeLaHkCSeHqXUihXLT2LglK+0GX3MBbFzde9x1uln2O68hH1tTmBg2O2i4Dtc4D3e+2tVv3XmhQDZt0znIVO6n9YgevDqw=

Cartfile

@@ -1,2 +0,0 @@
-github "Mantle/Mantle" ~> 1.5.3
-github "ReactiveCocoa/ReactiveCocoa" ~> 2.4.3

Cartfile.private

@@ -1,3 +0,0 @@
-github "jspahrsummers/xcconfigs" ~> 0.8.1
-github "Quick/Quick" ~> 1.1.0
-github "Quick/Nimble" ~> 6.1.0

Cartfile.resolved

@@ -1,5 +0,0 @@
-github "Mantle/Mantle" "1.5.8"
-github "Quick/Nimble" "v6.1.0"
-github "Quick/Quick" "v1.1.0"
-github "ReactiveCocoa/ReactiveCocoa" "v2.5"
-github "jspahrsummers/xcconfigs" "0.8.1"

README.md

@@ -6,7 +6,6 @@ and transparent as updates to a website**.
 Instead of publishing a feed of versions from which your app must select,
 Squirrel updates to the version your server tells it to. This allows you to
 intelligently update your clients based on the request you give to Squirrel.
-The server can remotely drive behaviors like rolling back or phased rollouts.
 
 Your request can include authentication details, custom headers or a request
 body so that your server has the context it needs in order to supply the most
@@ -14,49 +13,23 @@ suitable update.
 
 The update JSON Squirrel requests should be dynamically generated based on
 criteria in the request, and whether an update is required. Squirrel relies
-on server side support for determining whether an update is required, see
-[Server Support](#server-support).
+on server side support for determining whether an update is required, see [Server
+Support](#server-support) below.
 
-Squirrel's installer is also designed to be fault tolerant, and ensure that any
+Squirrel’s installer is also designed to be fault tolerant, and ensure that any
 updates installed are valid.
 
 ![:shipit:](http://shipitsquirrel.github.io/images/ship%20it%20squirrel.png)
 
 # Adopting Squirrel
 
-1. Install xctool with `brew install xctool`
 1. Add the Squirrel repository as a git submodule
-1. Run `script/bootstrap` from within the submodule
-1. Add references to Squirrel.xcodeproj and its [dependencies](#dependencies) to
-   your project
+1. Add a reference to Squirrel.xcodeproj to your project
 1. Add Squirrel.framework as a target dependency
 1. Link Squirrel.framework and add it to a Copy Files build phase which copies
 it into your Frameworks directory
-1. Ensure your application includes the [dependencies](#dependencies). Squirrel
-does not embed them itself.
-
-If you’re developing Squirrel on its own, then use `Squirrel.xcworkspace`.
-
-# Dependencies
-
-Squirrel depends on [ReactiveCocoa](http://github.com/ReactiveCocoa/ReactiveCocoa)
-and [Mantle](https://github.com/Mantle/Mantle).
-
-If your application is already using ReactiveCocoa, ensure it is using the same
-version as Squirrel.
-
-Otherwise, add a target dependency and Copy Files build phase entry for the
-ReactiveCocoa.framework target included in Squirrel's repository, in
-External/ReactiveCocoa.
-
-Similarly, ensure your application includes Mantle, or copies in the Squirrel
-version.
-
-Finally, ensure your application's Runpath Search Paths (`LD_RUNPATH_SEARCH_PATHS`)
-includes the directory that Squirrel.framework, ReactiveCocoa.framework
-and Mantle.framework are copied into.
-
-# Configuration
+1. Ensure your Runpath Search Paths (`LD_RUNPATH_SEARCH_PATHS`) includes the
+Frameworks directory Squirrel.framework is copied into
 
 Once Squirrel is added to your project, you need to configure and start it.
 
@@ -64,16 +37,7 @@ Once Squirrel is added to your project, you need to configure and start it.
 #import <Squirrel/Squirrel.h>
 
 - (void)applicationDidFinishLaunching:(NSNotification *)notification {
-	NSURLComponents *components = [[NSURLComponents alloc] init];
-
-	components.scheme = @"http";
-	components.host = @"mycompany.com";
-	components.path = @"/myapp/latest";
-
-	NSString *bundleVersion = NSBundle.mainBundle.sqrl_bundleVersion;
-	components.query = [[NSString stringWithFormat:@"version=%@", bundleVersion] stringByAddingPercentEncodingWithAllowedCharacters:NSCharacterSet.URLQueryAllowedCharacterSet]
-
-	self.updater = [[SQRLUpdater alloc] initWithUpdateRequest:[NSURLRequest requestWithURL:components.URL]];
+	self.updater = [[SQRLUpdater alloc] initWithUpdateRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"https://mycompany.com/myapp/latest"]]];
 
 	// Check for updates every 4 hours.
 	[self.updater startAutomaticChecksWithInterval:60 * 60 * 4];
@@ -84,26 +48,7 @@ Squirrel will periodically request and automatically download any updates. When
 your application terminates, any downloaded update will be automatically
 installed.
 
-## Update Requests
-
-Squirrel is indifferent to the request the client application provides for
-update checking. `Accept: application/json` is added to the request headers
-because Squirrel is responsible for parsing the response.
-
-For the requirements imposed on the responses and the body format of an update
-response see [Server Support](#server-support).
-
-Your update request must *at least* include a version identifier so that the
-server can determine whether an update for this specific version is required. It
-may also include other identifying criteria such as operating system version or
-username, to allow the server to deliver as fine grained an update as you
-would like.
-
-How you include the version identifier or other criteria is specific to the
-server that you are requesting updates from. A common approach is to use query
-parameters, [Configuration](#configuration) shows an example of this.
-
-## Update Available Notifications
+## Update Notifications
 
 To know when an update is ready to be installed, you can subscribe to the
 `updates` signal on `SQRLUpdater`:
@@ -114,18 +59,12 @@ To know when an update is ready to be installed, you can subscribe to the
 }];
 ```
 
-## Installing Updates
+If you've been notified of an available update, and don't want to wait for it to
+be installed automatically, you can terminate the app to begin the installation
+process immediately.
 
-While downloaded updates are automatically installed when your application
-terminates, if don't want to wait you can manually terminate the app to begin
-the installation process immediately.
-
-Once an [update available notification](#update-available-notifications) has
-been received, you may want to present an interface informing the user about
-the update and offering the ability to install and relaunch.
-
-To explicitly install a downloaded update and automatically relaunch afterward,
-subscribe to the `relaunchToInstallUpdate` signal on `SQRLUpdater`:
+If you want to install a downloaded update and automatically relaunch afterward,
+`SQRLUpdater` can do that:
 
 ```objc
 [[self.updater relaunchToInstallUpdate] subscribeError:^(NSError *error) {
@@ -133,33 +72,17 @@ subscribe to the `relaunchToInstallUpdate` signal on `SQRLUpdater`:
 }];
 ```
 
-# Server Support
+# Update JSON Format
 
-Your server should determine whether an update is required based on the
-[Update Request](#update-requests) your client issues.
-
-If an update is required your server should respond with a status code of
-[200 OK](http://tools.ietf.org/html/rfc2616#section-10.2.1) and include the
-[update JSON](#update-json-format) in the body. Squirrel **will** download and
-install this update, even if the version of the update is the same as the
-currently running version. To save redundantly downloading the same version
-multiple times your server must not inform the client to update.
-
-If no update is required your server must respond with a status code of
-[204 No Content](http://tools.ietf.org/html/rfc2616#section-10.2.5). Squirrel
-will check for an update again at the interval you specify.
-
-## Update JSON Format
-
-When an update is available, Squirrel expects the following schema in response
-to the update request provided:
+Squirrel requests the URL you provide with `Accept: application/json` and
+expects the following schema in response:
 
 ```json
 {
 	"url": "http://mycompany.com/myapp/releases/myrelease",
 	"name": "My Release Name",
 	"notes": "Theses are some release notes innit",
-	"pub_date": "2013-09-18T12:29:53+01:00"
+	"pub_date": "2013-09-18T12:29:53+01:00",
 }
 ```
 
@@ -170,10 +93,23 @@ installing ZIP updates. If future update formats are supported their MIME type
 will be added to the `Accept` header so that your server can return the
 appropriate format.
 
-"pub_date" if present must be formatted according to ISO 8601.
+"pub_date" if present must be formatted according to ISO 8601
+
+# Server Support
+
+If an update is required your server should respond with a status code of
+[200 OK](http://tools.ietf.org/html/rfc2616#section-10.2.1) and include the
+update JSON in the body. Squirrel **will** download and install this update,
+even if the version of the update is the same as the currently running version.
+To save redundantly downloading the same version multiple times your server must
+inform the client not to update.
+
+If no update is required your server must respond with a status code of
+[204 No Content](http://tools.ietf.org/html/rfc2616#section-10.2.5). Squirrel
+will check for an update again at the interval you specify.
 
 # User Interface
 
 Squirrel does not provide any GUI components for presenting updates. If you want
 to indicate updates to the user, make sure to [listen for downloaded
-updates](#update-available-notifications).
+updates](#update-notifications).

Squirrel.xcodeproj/xcshareddata/xcschemes/Squirrel.xcscheme

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0830"
-   version = "2.0">
+   LastUpgradeVersion = "0500"
+   version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
       buildImplicitDependencies = "YES">
@@ -22,14 +22,14 @@
          </BuildActionEntry>
          <BuildActionEntry
             buildForTesting = "YES"
-            buildForRunning = "NO"
+            buildForRunning = "YES"
             buildForProfiling = "NO"
             buildForArchiving = "NO"
-            buildForAnalyzing = "NO">
+            buildForAnalyzing = "YES">
             <BuildableReference
                BuildableIdentifier = "primary"
                BlueprintIdentifier = "D0C22BEE179CC00E00158214"
-               BuildableName = "SquirrelTests.xctest"
+               BuildableName = "SquirrelTests.octest"
                BlueprintName = "SquirrelTests"
                ReferencedContainer = "container:Squirrel.xcodeproj">
             </BuildableReference>
@@ -37,61 +37,32 @@
       </BuildActionEntries>
    </BuildAction>
    <TestAction
-      buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "NO">
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      buildConfiguration = "Test">
       <Testables>
          <TestableReference
             skipped = "NO">
             <BuildableReference
                BuildableIdentifier = "primary"
                BlueprintIdentifier = "D0C22BEE179CC00E00158214"
-               BuildableName = "SquirrelTests.xctest"
+               BuildableName = "SquirrelTests.octest"
                BlueprintName = "SquirrelTests"
                ReferencedContainer = "container:Squirrel.xcodeproj">
             </BuildableReference>
          </TestableReference>
       </Testables>
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "D0C22BD6179CC00E00158214"
-            BuildableName = "Squirrel.framework"
-            BlueprintName = "Squirrel"
-            ReferencedContainer = "container:Squirrel.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
-      <EnvironmentVariables>
-         <EnvironmentVariable
-            key = "FORCE_APP_IDENTIFIER"
-            value = "com.github.Squirrel.SquirrelTests"
-            isEnabled = "YES">
-         </EnvironmentVariable>
-      </EnvironmentVariables>
-      <AdditionalOptions>
-      </AdditionalOptions>
    </TestAction>
    <LaunchAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = ""
-      selectedLauncherIdentifier = "Xcode.IDEFoundation.Launcher.PosixSpawn"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
+      buildConfiguration = "Debug"
       ignoresPersistentStateOnLaunch = "NO"
       debugDocumentVersioning = "YES"
-      debugXPCServices = "NO"
-      debugServiceExtension = "internal"
       allowLocationSimulation = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "D0C22BD6179CC00E00158214"
-            BuildableName = "Squirrel.framework"
-            BlueprintName = "Squirrel"
-            ReferencedContainer = "container:Squirrel.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
       <EnvironmentVariables>
          <EnvironmentVariable
             key = "SQRLUpdateFromURL"
@@ -103,20 +74,11 @@
       </AdditionalOptions>
    </LaunchAction>
    <ProfileAction
-      buildConfiguration = "Profile"
       shouldUseLaunchSchemeArgsEnv = "YES"
       savedToolIdentifier = ""
       useCustomWorkingDirectory = "NO"
+      buildConfiguration = "Profile"
       debugDocumentVersioning = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "D0C22BD6179CC00E00158214"
-            BuildableName = "Squirrel.framework"
-            BlueprintName = "Squirrel"
-            ReferencedContainer = "container:Squirrel.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
    </ProfileAction>
    <AnalyzeAction
       buildConfiguration = "Debug">

Squirrel.xcodeproj/xcshareddata/xcschemes/TestApplication.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0830"
+   LastUpgradeVersion = "0500"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -23,10 +23,10 @@
       </BuildActionEntries>
    </BuildAction>
    <TestAction
-      buildConfiguration = "Test"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "YES">
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      buildConfiguration = "Test">
       <Testables>
       </Testables>
       <MacroExpansion>
@@ -38,21 +38,17 @@
             ReferencedContainer = "container:Squirrel.xcodeproj">
          </BuildableReference>
       </MacroExpansion>
-      <AdditionalOptions>
-      </AdditionalOptions>
    </TestAction>
    <LaunchAction
-      buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
+      buildConfiguration = "Debug"
       ignoresPersistentStateOnLaunch = "NO"
       debugDocumentVersioning = "YES"
-      debugServiceExtension = "internal"
       allowLocationSimulation = "YES">
-      <BuildableProductRunnable
-         runnableDebuggingMode = "0">
+      <BuildableProductRunnable>
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "D08D4E0B17B451500012B22D"
@@ -65,13 +61,12 @@
       </AdditionalOptions>
    </LaunchAction>
    <ProfileAction
-      buildConfiguration = "Release"
       shouldUseLaunchSchemeArgsEnv = "YES"
       savedToolIdentifier = ""
       useCustomWorkingDirectory = "NO"
+      buildConfiguration = "Release"
       debugDocumentVersioning = "YES">
-      <BuildableProductRunnable
-         runnableDebuggingMode = "0">
+      <BuildableProductRunnable>
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "D08D4E0B17B451500012B22D"

Squirrel.xcodeproj/xcshareddata/xcschemes/shipit.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0830"
+   LastUpgradeVersion = "0500"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -20,45 +20,47 @@
                ReferencedContainer = "container:Squirrel.xcodeproj">
             </BuildableReference>
          </BuildActionEntry>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "NO"
+            buildForArchiving = "NO"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "D0C22BEE179CC00E00158214"
+               BuildableName = "SquirrelTests.octest"
+               BlueprintName = "SquirrelTests"
+               ReferencedContainer = "container:Squirrel.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
       </BuildActionEntries>
    </BuildAction>
    <TestAction
-      buildConfiguration = "Test"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "YES">
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      buildConfiguration = "Test">
       <Testables>
       </Testables>
-      <AdditionalOptions>
-      </AdditionalOptions>
    </TestAction>
    <LaunchAction
-      buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
+      buildConfiguration = "Debug"
       ignoresPersistentStateOnLaunch = "NO"
       debugDocumentVersioning = "YES"
-      debugServiceExtension = "internal"
       allowLocationSimulation = "YES">
-      <MacroExpansion>
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "D014AC0017B97885007D79D0"
-            BuildableName = "ShipIt"
-            BlueprintName = "ShipIt"
-            ReferencedContainer = "container:Squirrel.xcodeproj">
-         </BuildableReference>
-      </MacroExpansion>
       <AdditionalOptions>
       </AdditionalOptions>
    </LaunchAction>
    <ProfileAction
-      buildConfiguration = "Release"
       shouldUseLaunchSchemeArgsEnv = "YES"
       savedToolIdentifier = ""
       useCustomWorkingDirectory = "NO"
+      buildConfiguration = "Release"
       debugDocumentVersioning = "YES">
    </ProfileAction>
    <AnalyzeAction

Squirrel.xcworkspace/contents.xcworkspacedata

@@ -1,22 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Workspace
-   version = "1.0">
-   <FileRef
-      location = "group:Squirrel.xcodeproj">
-   </FileRef>
-   <FileRef
-      location = "group:Carthage/Checkouts/Mantle/Mantle.xcodeproj">
-   </FileRef>
-   <FileRef
-      location = "group:Carthage/Checkouts/ReactiveCocoa/ReactiveCocoa.xcodeproj">
-   </FileRef>
-   <FileRef
-      location = "group:External/OHHTTPStubs/OHHTTPStubs/OHHTTPStubs.xcodeproj">
-   </FileRef>
-   <FileRef
-      location = "group:Carthage/Checkouts/Quick/Quick.xcodeproj">
-   </FileRef>
-   <FileRef
-      location = "group:Carthage/Checkouts/Nimble/Nimble.xcodeproj">
-   </FileRef>
-</Workspace>

Squirrel/NSBundle+SQRLVersionExtensions.h

@@ -14,7 +14,4 @@
 // Info.plist, or nil if the key is not present.
 @property (nonatomic, copy, readonly) NSString *sqrl_bundleVersion;
 
-/// The value of the `kCFBundleExecutableKey` key.
-@property (nonatomic, copy, readonly) NSString *sqrl_executableName;
-
 @end

Squirrel/NSBundle+SQRLVersionExtensions.m

@@ -14,8 +14,4 @@
 	return [self objectForInfoDictionaryKey:(id)kCFBundleVersionKey];
 }
 
-- (NSString *)sqrl_executableName {
-	return [self objectForInfoDictionaryKey:(id)kCFBundleExecutableKey];
-}
-
 @end

Squirrel/NSData+SQRLExtensions.h

@@ -0,0 +1,19 @@
+//
+//  NSData+SQRLExtensions.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 21/01/2014.
+//  Copyright (c) 2014 GitHub. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+@interface NSData (SQRLExtensions)
+
+// Returns an NSData for the SHA1 hash of the receiver.
+- (NSData *)sqrl_SHA1Hash;
+
+// Returns the base16 encoding of the receiver.
+- (NSString *)sqrl_base16String;
+
+@end

Squirrel/NSData+SQRLExtensions.m

@@ -0,0 +1,31 @@
+//
+//  NSData+SQRLExtensions.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 21/01/2014.
+//  Copyright (c) 2014 GitHub. All rights reserved.
+//
+
+#import "NSData+SQRLExtensions.h"
+
+#import <CommonCrypto/CommonCrypto.h>
+
+@implementation NSData (SQRLExtensions)
+
+- (NSData *)sqrl_SHA1Hash {
+	unsigned char hash[CC_SHA1_DIGEST_LENGTH];
+	CC_SHA1(self.bytes, (CC_LONG)self.length, hash);
+	return [NSData dataWithBytes:hash length:sizeof(hash) / sizeof(*hash)];
+}
+
+- (NSString *)sqrl_base16String {
+	NSMutableString *base16 = [NSMutableString stringWithCapacity:self.length * 2];
+	uint8_t *bytes = (uint8_t *)self.bytes;
+	for (NSUInteger idx = 0; idx < self.length; idx++) {
+		uint8_t byte = *(bytes + idx);
+		[base16 appendFormat:@"%02hhx", byte];
+	}
+	return base16;
+}
+
+@end

Squirrel/NSHTTPURLResponse+SQRLExtensions.h

@@ -0,0 +1,18 @@
+//
+//  NSHTTPURLResponse+SQRLExtensions.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 04/12/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+@interface NSHTTPURLResponse (SQRLExtensions)
+
+// Case insensitively look up a header field value.
+//
+// Returns the value of the header if present or nil otherwise.
+- (NSString *)sqrl_valueForHTTPHeaderField:(NSString *)field;
+
+@end

Squirrel/NSHTTPURLResponse+SQRLExtensions.m

@@ -0,0 +1,26 @@
+//
+//  NSHTTPURLResponse+SQRLExtensions.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 04/12/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "NSHTTPURLResponse+SQRLExtensions.h"
+
+#import <ReactiveCocoa/ReactiveCocoa.h>
+
+@implementation NSHTTPURLResponse (SQRLExtensions)
+
+- (NSString *)sqrl_valueForHTTPHeaderField:(NSString *)field {
+	return [[[self.allHeaderFields.rac_signal
+		filter:^ BOOL (RACTuple *keyValuePair) {
+			return [keyValuePair[0] caseInsensitiveCompare:field] == NSOrderedSame;
+		}]
+		reduceEach:^(NSString *key, NSString *value) {
+			return value;
+		}]
+		first];
+}
+
+@end

Squirrel/RACSignal+SQRLFileManagerExtensions.h

@@ -0,0 +1,15 @@
+//
+//  RACSignal+SQRLFileManagerExtensions.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 21/01/2014.
+//  Copyright (c) 2014 GitHub. All rights reserved.
+//
+
+#import <ReactiveCocoa/ReactiveCocoa.h>
+
+@interface RACSignal (SQRLFileManagerExtensions)
+
+- (RACSignal *)sqrl_tryCreateDirectory;
+
+@end

Squirrel/RACSignal+SQRLFileManagerExtensions.m

@@ -0,0 +1,21 @@
+//
+//  RACSignal+SQRLFileManagerExtensions.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 21/01/2014.
+//  Copyright (c) 2014 GitHub. All rights reserved.
+//
+
+#import "RACSignal+SQRLFileManagerExtensions.h"
+
+@implementation RACSignal (SQRLFileManagerExtensions)
+
+- (RACSignal *)sqrl_tryCreateDirectory {
+	return [[self
+		try:^(NSURL *directoryURL, NSError **errorRef) {
+			return [NSFileManager.defaultManager createDirectoryAtURL:directoryURL withIntermediateDirectories:YES attributes:nil error:errorRef];
+		}]
+		setNameWithFormat:@"%@ -sqrl_tryCreateDirectory", self];
+}
+
+@end

Squirrel/RACSignal+SQRLTransactionExtensions.h

@@ -6,7 +6,7 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <ReactiveCocoa/RACSignal.h>
+#import <ReactiveCocoa/ReactiveCocoa.h>
 
 @interface RACSignal (SQRLTransactionExtensions)
 

Squirrel/RACSignal+SQRLTransactionExtensions.m

@@ -7,8 +7,6 @@
 //
 
 #import "RACSignal+SQRLTransactionExtensions.h"
-
-#import <ReactiveCocoa/RACDisposable.h>
 #import <IOKit/pwr_mgt/IOPMLib.h>
 
 // How long before power assertions time out.
@@ -99,15 +97,12 @@ static RACDisposable *SQRLCreateTransaction(NSString *name, NSString *descriptio
 		va_end(args);
 	}
 
-	return [[RACSignal createSignal:^(id<RACSubscriber> subscriber) {
-		RACDisposable *transactionDisposable = SQRLCreateTransaction(name, description);
-		RACDisposable *subscriptionDisposable = [self subscribe:subscriber];
-
-		return [RACDisposable disposableWithBlock:^{
-			[subscriptionDisposable dispose];
-			[transactionDisposable dispose];
-		}];
-	}] setNameWithFormat:@"[%@] -sqrl_addTransactionWithName: %@ description: %@", self.name, name, description];
+	return [[RACSignal
+		create:^(id<RACSubscriber> subscriber) {
+			[subscriber.disposable addDisposable:SQRLCreateTransaction(name, description)];
+			[self subscribe:subscriber];
+		}]
+		setNameWithFormat:@"[%@] -sqrl_addTransactionWithName: %@ description: %@", self.name, name, description];
 }
 
 - (RACSignal *)sqrl_addSubscriptionTransactionWithName:(NSString *)name description:(NSString *)descriptionFormat, ... {
@@ -119,13 +114,13 @@ static RACDisposable *SQRLCreateTransaction(NSString *name, NSString *descriptio
 		va_end(args);
 	}
 
-	return [[RACSignal createSignal:^(id<RACSubscriber> subscriber) {
-		RACDisposable *transactionDisposable = SQRLCreateTransaction(name, description);
-		RACDisposable *subscriptionDisposable = [self subscribe:subscriber];
-		[transactionDisposable dispose];
-
-		return subscriptionDisposable;
-	}] setNameWithFormat:@"[%@] -sqrl_addSubscriptionTransactionWithName: %@ description: %@", self.name, name, description];
+	return [[RACSignal
+		create:^(id<RACSubscriber> subscriber) {
+			RACDisposable *transactionDisposable = SQRLCreateTransaction(name, description);
+			[self subscribe:subscriber];
+			[transactionDisposable dispose];
+		}]
+		setNameWithFormat:@"[%@] -sqrl_addSubscriptionTransactionWithName: %@ description: %@", self.name, name, description];
 }
 
 @end

Squirrel/SQRLAuthorization.h

@@ -1,27 +0,0 @@
-//
-//  SQRLAuthorization.h
-//  Squirrel
-//
-//  Created by Keith Duncan on 06/01/2014.
-//  Copyright (c) 2014 GitHub. All rights reserved.
-//
-
-#import <Foundation/Foundation.h>
-
-#import <Security/Security.h>
-
-// Wraps an AuthorizationRef.
-@interface SQRLAuthorization : NSObject
-
-// Designated initializer.
-//
-// authorization - Must not be NULL, the returned object assumes ownership of
-//                 the passed authorization.
-//
-// Returns an object which ties the `authorization` argument to the returned
-// object's lifetime.
-- (instancetype)initWithAuthorization:(AuthorizationRef)authorization;
-
-@property (readonly, nonatomic, assign) AuthorizationRef authorization;
-
-@end

Squirrel/SQRLAuthorization.m

@@ -1,28 +0,0 @@
-//
-//  SQRLAuthorization.m
-//  Squirrel
-//
-//  Created by Keith Duncan on 06/01/2014.
-//  Copyright (c) 2014 GitHub. All rights reserved.
-//
-
-#import "SQRLAuthorization.h"
-
-@implementation SQRLAuthorization
-
-- (instancetype)initWithAuthorization:(AuthorizationRef)authorization {
-	NSParameterAssert(authorization != NULL);
-
-	self = [self init];
-	if (self == nil) return nil;
-
-	_authorization = authorization;
-
-	return self;
-}
-
-- (void)dealloc {
-	if (_authorization != NULL) AuthorizationFree(_authorization, kAuthorizationFlagDestroyRights);
-}
-
-@end

Squirrel/SQRLCodeSignature.h

@@ -21,44 +21,32 @@ extern const NSInteger SQRLCodeSignatureErrorCouldNotCreateStaticCode;
 
 @class RACSignal;
 
-// Implements the verification of Apple code signatures and requirements.
+// Implements the verification of Apple code signatures.
 @interface SQRLCodeSignature : MTLModel
 
 // A serialized version of the `SecRequirementRef` that the receiver was
 // initialized with.
 @property (nonatomic, copy, readonly) NSData *requirementData;
 
-// Determines the designated requirement of the currently-executing application.
-// The returned code signature can be used to verify that a bundle is code sign
-// valid and meets the designated requirement of the current application.
+// Determines the code signature of the currently-executing application.
 //
 // error - If not NULL, set to any error that occurs.
 //
 // Returns a `SQRLCodeSignature`, or nil if an error occurs retrieving the
-// designated requirement for the running code.
+// signature for the running code.
 + (instancetype)currentApplicationSignature:(NSError **)error;
 
-// Determines the designated requirement of the specified bundle. The returned
-// code signature can be used to verify that an arbitrary bundle is valid and
-// meets the designated requirement of `bundle`.
+// Initializes the receiver with the given requirement.
 //
-// bundleURL - Must not be nil, the location of a bundle directory structure
-//             which has been code signed and includes a designated requirement.
-//             This bundle's designated requirement is used when verifying other
-//             bundles.
-// error     - If not NULL, set to any error that occurs.
-//
-// Returns a `SQRLCodeSignature`, or nil if an error occurs retrieving the
-// designated requirement of the bundle at `bundleURL`.
-+ (instancetype)signatureWithBundle:(NSURL *)bundleURL error:(NSError **)error;
+// requirement - The code requirement for tested bundles. This must not be NULL.
+- (id)initWithRequirement:(SecRequirementRef)requirement;
 
-// Verifies the code signature of the specified bundle and verifies that the
-// bundle meets the receiver's requirement.
+// Verifies that the code signature of the specified bundle matches the receiver.
 //
 // bundleURL - The URL to the bundle to verify on disk. This must not be nil.
 //
 // Returns a signal which will synchronously send completed on success, or error
-// if the requirement was not verified successfully.
+// if the code signature was not verified successfully.
 - (RACSignal *)verifyBundleAtURL:(NSURL *)bundleURL;
 
 @end

Squirrel/SQRLCodeSignature.m

@@ -7,11 +7,8 @@
 //
 
 #import "SQRLCodeSignature.h"
-
-#import "EXTKeyPathCoding.h"
-#import "EXTScope.h"
-#import <ReactiveCocoa/RACSignal+Operations.h>
-#import <ReactiveCocoa/RACSubscriber.h>
+#import <ReactiveCocoa/EXTScope.h>
+#import <ReactiveCocoa/ReactiveCocoa.h>
 #import <Security/Security.h>
 
 NSString * const SQRLCodeSignatureErrorDomain = @"SQRLCodeSignatureErrorDomain";
@@ -22,14 +19,9 @@ const NSInteger SQRLCodeSignatureErrorCouldNotCreateStaticCode = -2;
 @interface SQRLCodeSignature ()
 
 // A `SecRequirementRef` that tested bundles must satisfy.
-@property (atomic, strong) id requirement;
-
-// Initializes the receiver with the given requirement.
 //
-// This is the designated initializer for this class.
-//
-// requirement - The code requirement for tested bundles. This must not be NULL.
-- (id)initWithRequirement:(SecRequirementRef)requirement;
+// This property is automatically retained.
+@property (atomic) id requirement;
 
 @end
 
@@ -45,49 +37,8 @@ const NSInteger SQRLCodeSignatureErrorCouldNotCreateStaticCode = -2;
 
 #pragma mark Lifecycle
 
-+ (instancetype)currentApplicationSignature:(NSError **)errorRef {
-	SecCodeRef staticCode = NULL;
-	OSStatus error = SecCodeCopySelf(kSecCSDefaultFlags, &staticCode);
-	if (error != noErr) {
-		if (errorRef != NULL) *errorRef = [NSError errorWithDomain:NSOSStatusErrorDomain code:error userInfo:nil];
-		return nil;
-	}
-
-	@onExit {
-		CFRelease(staticCode);
-	};
-
-	return [self signatureWithCode:staticCode error:errorRef];
-}
-
-+ (instancetype)signatureWithBundle:(NSURL *)bundleURL error:(NSError **)errorRef {
-	SecStaticCodeRef bundleCode = NULL;
-	OSStatus error = SecStaticCodeCreateWithPath((__bridge CFURLRef)bundleURL, kSecCSDefaultFlags, &bundleCode);
-	if (error != noErr) {
-		if (errorRef != NULL) *errorRef = [NSError errorWithDomain:NSOSStatusErrorDomain code:error userInfo:nil];
-		return nil;
-	}
-
-	@onExit {
-		CFRelease(bundleCode);
-	};
-
-	return [self signatureWithCode:bundleCode error:errorRef];
-}
-
-+ (instancetype)signatureWithCode:(SecStaticCodeRef)code error:(NSError **)errorRef {
-	SecRequirementRef designatedRequirement = NULL;
-	OSStatus error = SecCodeCopyDesignatedRequirement(code, kSecCSDefaultFlags, &designatedRequirement);
-	if (error != noErr) {
-		if (errorRef != NULL) *errorRef = [NSError errorWithDomain:NSOSStatusErrorDomain code:error userInfo:nil];
-		return nil;
-	}
-
-	@onExit {
-		CFRelease(designatedRequirement);
-	};
-
-	return [[SQRLCodeSignature alloc] initWithRequirement:designatedRequirement];
++ (instancetype)currentApplicationSignature:(NSError **)error {
+	return [self modelWithDictionary:nil error:error];
 }
 
 - (id)initWithRequirement:(SecRequirementRef)requirement {
@@ -98,12 +49,41 @@ const NSInteger SQRLCodeSignatureErrorCouldNotCreateStaticCode = -2;
 	} error:NULL];
 }
 
+- (id)initWithDictionary:(NSDictionary *)dictionary error:(NSError **)error {
+	self = [super initWithDictionary:dictionary error:error];
+	if (self == nil) return nil;
+
+	if (self.requirement == nil) {
+		SecCodeRef staticCode = NULL;
+		OSStatus result = SecCodeCopySelf(kSecCSDefaultFlags, &staticCode);
+		@onExit {
+			if (staticCode != NULL) CFRelease(staticCode);
+		};
+
+		if (result != noErr) {
+			if (error != NULL) *error = [NSError errorWithDomain:NSOSStatusErrorDomain code:result userInfo:nil];
+			return nil;
+		}
+
+		SecRequirementRef req = NULL;
+		result = SecCodeCopyDesignatedRequirement(staticCode, kSecCSDefaultFlags, &req);
+		self.requirement = CFBridgingRelease(req);
+
+		if (result != noErr) {
+			if (error != NULL) *error = [NSError errorWithDomain:NSOSStatusErrorDomain code:result userInfo:nil];
+			return nil;
+		}
+	}
+
+	return self;
+}
+
 #pragma mark Verification
 
 - (RACSignal *)verifyBundleAtURL:(NSURL *)bundleURL {
 	NSParameterAssert(bundleURL != nil);
 
-	return [[RACSignal createSignal:^ RACDisposable * (id<RACSubscriber> subscriber) {
+	return [[RACSignal create:^(id<RACSubscriber> subscriber) {
 		SecStaticCodeRef staticCode = NULL;
 		
 		OSStatus result = SecStaticCodeCreateWithPath((__bridge CFURLRef)bundleURL, kSecCSDefaultFlags, &staticCode);
@@ -120,8 +100,10 @@ const NSInteger SQRLCodeSignatureErrorCouldNotCreateStaticCode = -2;
 			if (failureReason != nil) userInfo[NSLocalizedFailureReasonErrorKey] = failureReason;
 			
 			[subscriber sendError:[NSError errorWithDomain:SQRLCodeSignatureErrorDomain code:SQRLCodeSignatureErrorCouldNotCreateStaticCode userInfo:userInfo]];
-			return nil;
+			return;
 		}
+
+		if (subscriber.disposable.disposed) return;
 		
 		CFErrorRef validityError = NULL;
 		result = SecStaticCodeCheckValidityWithErrors(staticCode, kSecCSCheckAllArchitectures, (__bridge SecRequirementRef)self.requirement, &validityError);
@@ -139,11 +121,10 @@ const NSInteger SQRLCodeSignatureErrorCouldNotCreateStaticCode = -2;
 			if (validityError != NULL) userInfo[NSUnderlyingErrorKey] = (__bridge NSError *)validityError;
 			
 			[subscriber sendError:[NSError errorWithDomain:SQRLCodeSignatureErrorDomain code:SQRLCodeSignatureErrorDidNotPass userInfo:userInfo]];
-			return nil;
+			return;
 		}
 		
 		[subscriber sendCompleted];
-		return nil;
 	}] setNameWithFormat:@"-verifyCodeSignatureOfBundle: %@", bundleURL];
 }
 

Squirrel/SQRLDirectoryManager.h

@@ -6,16 +6,13 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Cocoa/Cocoa.h>
+#import <Foundation/Foundation.h>
 
 @class RACSignal;
 
 // Provides the file locations that Squirrel/ShipIt use.
 @interface SQRLDirectoryManager : NSObject
 
-// The application identifier to use in file locations.
-@property (nonatomic, copy, readonly) NSString *applicationIdentifier;
-
 // Returns the shared `SQRLDirectoryManager` for the running application, based
 // on the bundle identifier or application name.
 + (instancetype)currentApplicationManager;
@@ -29,24 +26,27 @@
 //                 on-disk locations for. This must not be nil.
 - (instancetype)initWithApplicationIdentifier:(NSString *)appIdentifier;
 
-// Finds or creates a storage folder.
+// Finds or creates an Application Support subdirectory for the receiver’s
+// application identifier.
 //
 // Returns a signal which synchronously sends a URL then completes, or errors.
-- (RACSignal *)storageURL;
+@property (readonly, nonatomic) RACSignal *applicationSupportURL;
+
+// Finds or creates a downloads directory to store update downloads in prior to
+// installation. This is an applicationSupportURL subdirectory.
+//
+// Returns a signal which sends a URL then completes, or errors.
+@property (readonly, nonatomic) RACSignal *downloadDirectoryURL;
+
+// Creates a new directory to unpack a downloaded update into prior to
+// installation. This is an applicationSupportURL subdirectory.
+//
+// Returns a signal which sends a URL then completes, or errors.
+- (RACSignal *)createUniqueUpdateDirectoryURL;
 
 // Determines where archived `SQRLShipItState` should be saved.
 //
 // Returns a signal which synchronously sends a URL then completes, or errors.
-- (RACSignal *)shipItStateURL;
-
-// Determines where ShipIt's stdout log should be saved.
-//
-// Returns a signal which synchronously sends a URL then completes, or errors.
-- (RACSignal *)shipItStdoutURL;
-
-// Determines where ShipIt's stderr log should be saved.
-//
-// Returns a signal which synchronously sends a URL then completes, or errors.
-- (RACSignal *)shipItStderrURL;
+@property (readonly, nonatomic) RACSignal *shipItStateURL;
 
 @end

Squirrel/SQRLDirectoryManager.m

@@ -7,8 +7,16 @@
 //
 
 #import "SQRLDirectoryManager.h"
+#import <ReactiveCocoa/ReactiveCocoa.h>
+#import <ReactiveCocoa/EXTScope.h>
+#import "RACSignal+SQRLFileManagerExtensions.h"
 
-#import <ReactiveCocoa/RACSignal+Operations.h>
+@interface SQRLDirectoryManager ()
+
+// The application identifier to use in file locations.
+@property (nonatomic, copy, readonly) NSString *applicationIdentifier;
+
+@end
 
 @implementation SQRLDirectoryManager
 
@@ -24,7 +32,7 @@
 		// Should only fallback to when running under otest, where
 		// NSBundle.mainBundle doesn't return useful data.
 		if (identifier == nil) {
-			identifier = NSProcessInfo.processInfo.environment[@"FORCE_APP_IDENTIFIER"];
+			identifier = NSRunningApplication.currentApplication.localizedName;
 		}
 
 		NSAssert(identifier != nil, @"Could not automatically determine the current application's identifier");
@@ -47,52 +55,74 @@
 
 #pragma mark Folder URLs
 
-- (RACSignal *)storageURL {
-	return [[RACSignal
++ (NSString *)fileSystemNameForIdentifier:(NSString *)identifier {
+	// Periods are problematic in the filesystem because they denote file type.
+	// A directory can become a package which can be undesirable.
+	return [identifier stringByReplacingOccurrencesOfString:@"." withString:@"~"];
+}
+
+- (RACSignal *)applicationSupportURL {
+	return [[[[RACSignal
 		defer:^{
 			NSError *error = nil;
-			NSURL *folderURL = [NSFileManager.defaultManager URLForDirectory:NSCachesDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:YES error:&error];
-			if (folderURL == nil) {
+			NSURL *directoryURL = [NSFileManager.defaultManager URLForDirectory:NSApplicationSupportDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:YES error:&error];
+			if (directoryURL == nil) {
 				return [RACSignal error:error];
 			}
 
-			folderURL = [folderURL URLByAppendingPathComponent:self.applicationIdentifier];
-			if (![NSFileManager.defaultManager createDirectoryAtURL:folderURL withIntermediateDirectories:YES attributes:nil error:&error]) {
-				return [RACSignal error:error];
-			}
-
-			return [RACSignal return:folderURL];
+			return [RACSignal return:directoryURL];
 		}]
-		setNameWithFormat:@"%@ -storageURL", self];
+		map:^ (NSURL *directoryURL) {
+			RACSignal *identifierComponents = [@[ self.applicationIdentifier, @"com.github.Squirrel" ].rac_signal
+				map:^(NSString *name) {
+					return [self.class fileSystemNameForIdentifier:name];
+				}];
+
+			RACSignal *pathComponents = [directoryURL.pathComponents.rac_signal concat:identifierComponents];
+			return [NSURL fileURLWithPathComponents:[pathComponents array]];
+		}]
+		sqrl_tryCreateDirectory]
+		setNameWithFormat:@"%@ -applicationSupportURL", self];
+}
+
+- (RACSignal *)downloadDirectoryURL {
+	return [[[[self
+		applicationSupportURL]
+		map:^(NSURL *directoryURL) {
+			return [directoryURL URLByAppendingPathComponent:@"downloads"];
+		}]
+		sqrl_tryCreateDirectory]
+		setNameWithFormat:@"%@ -downloadDirectoryURL", self];
+}
+
+- (RACSignal *)createUniqueUpdateDirectoryURL {
+	return [[[[self
+		applicationSupportURL]
+		map:^(NSURL *directoryURL) {
+			// noindex so that Spotlight doesn't pick up apps pending update and
+			// add them to the Launch Services database.
+			return [[directoryURL URLByAppendingPathComponent:NSProcessInfo.processInfo.globallyUniqueString] URLByAppendingPathExtension:@"noindex"];
+		}]
+		try:^(NSURL *directoryURL, NSError **errorRef) {
+			// Explicitly just provide the owner with permission, discarding the
+			// current umask. This matches the `mkdtemp` behaviour.
+			NSDictionary *directoryAttributes = @{
+				NSFilePosixPermissions: @(S_IRWXU),
+			};
+			return [NSFileManager.defaultManager createDirectoryAtURL:directoryURL withIntermediateDirectories:YES attributes:directoryAttributes error:errorRef];
+		}]
+		setNameWithFormat:@"%@ -createUniqueUpdateDirectoryURL", self];
 }
 
 - (RACSignal *)shipItStateURL {
 	return [[[self
-		storageURL]
+		applicationSupportURL]
 		map:^(NSURL *folderURL) {
 			return [folderURL URLByAppendingPathComponent:@"ShipItState.plist"];
 		}]
 		setNameWithFormat:@"%@ -shipItStateURL", self];
 }
 
-- (RACSignal *)shipItStdoutURL {
-	return [[[self
-		storageURL]
-		map:^(NSURL *folderURL) {
-			return [folderURL URLByAppendingPathComponent:@"ShipIt_stdout.log"];
-		}]
-		setNameWithFormat:@"%@ -shipItStdoutURL", self];
-}
-
-- (RACSignal *)shipItStderrURL {
-	return [[[self
-		storageURL]
-		map:^(NSURL *folderURL) {
-			return [folderURL URLByAppendingPathComponent:@"ShipIt_stderr.log"];
-		}]
-		setNameWithFormat:@"%@ -shipItStderrURL", self];
-}
-
 #pragma mark NSObject
 
 - (NSString *)description {

Squirrel/SQRLDownload+Private.h

@@ -0,0 +1,21 @@
+//
+//  SQRLDownload+Private.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 21/01/2014.
+//  Copyright (c) 2014 GitHub. All rights reserved.
+//
+
+#import "SQRLDownload.h"
+
+@interface SQRLDownload ()
+
+// Designated initialiser.
+//
+// request - Must not be nil. The request this download is for.
+// fileURL - Must not be nil. The file location to save received data to.
+//
+// Returns an initialised download suitable for saving response data.
+- (instancetype)initWithRequest:(NSURLRequest *)request fileURL:(NSURL *)fileURL;
+
+@end

Squirrel/SQRLDownload.h

@@ -0,0 +1,31 @@
+//
+//  SQRLDownload.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 21/11/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import <Mantle/Mantle.h>
+
+@class RACSignal;
+
+// A download is a file which holds the response body for a request and can be
+// resumed by a subsequent request if the initial transfer is interrupted.
+//
+// Don't create a download directly, instead retrieve one from
+// `SQRLDownloadManager`.
+@interface SQRLDownload : MTLModel
+
+// The `request` the receiver was initialised with.
+@property (readonly, copy, nonatomic) NSURLRequest *request;
+
+// The `fileURL` the receiver was initialised with.
+@property (readonly, copy, nonatomic) NSURL *fileURL;
+
+// Calculate a request suitable for resuming the download.
+//
+// Returns a signal which sends an `NSURLRequest` then completes.
+@property (readonly, nonatomic) RACSignal *resumableRequest;
+
+@end

Squirrel/SQRLDownload.m

@@ -0,0 +1,29 @@
+//
+//  SQRLDownload.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 21/11/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLDownload.h"
+#import "SQRLDownload+Private.h"
+
+#import <ReactiveCocoa/ReactiveCocoa.h>
+
+@implementation SQRLDownload
+
+- (instancetype)initWithRequest:(NSURLRequest *)request fileURL:(NSURL *)fileURL {
+	return [self initWithDictionary:@{
+		@keypath(self.request): request,
+		@keypath(self.fileURL): fileURL,
+	} error:NULL];
+}
+
+- (RACSignal *)resumableRequest {
+	return [[RACSignal
+		return:self.request]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+@end

Squirrel/SQRLDownloadManager.h

@@ -0,0 +1,61 @@
+//
+//  SQRLDownloadController.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 26/09/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+@class SQRLDownload;
+@class SQRLResumableDownload;
+@class RACSignal;
+@class SQRLDirectoryManager;
+
+// Stores metadata for download resumption, and manages the disk locations for
+// where they're stored.
+@interface SQRLDownloadManager : NSObject
+
+// Default download manager, initializes a download manager with the current
+// application directory manager. Stores downloads in
+// `directoryManager.downloadDirectoryURL`.
++ (instancetype)defaultDownloadManager;
+
+// Designated initialiser.
+//
+// directoryManager - Must not be nil.
+//
+// Returns a download manager which can resume previously started downloads for
+// the initialised directory manager's application.
+- (instancetype)initWithDirectoryManager:(SQRLDirectoryManager *)directoryManager;
+
+// Clean the resumable download state, removes downloaded data and tracking
+// state.
+//
+// Returns a signal which errors or completes when all file operations have been
+// attempted.
+- (RACSignal *)removeAllResumableDownloads;
+
+// Retrieve a previously started download, or initialise a new download.
+//
+// Previously started downloads may have been removed and require
+// reinitialising.
+//
+// request - The request you are performing and require a disk location to save
+//           the response body to. Must not be nil.
+//
+// Returns a signal which sends an `SQRLDownload` object then completes, or
+// errors.
+- (RACSignal *)downloadForRequest:(NSURLRequest *)request;
+
+// Store metadata for a download so that it can be resumed later.
+//
+// download - The download being stored for future resumption. Must not be nil.
+// request  - The request for which the download can be resumed. Must not be
+//            nil.
+//
+// Returns a signal which completes or errors.
+- (RACSignal *)setDownload:(SQRLResumableDownload *)download forRequest:(NSURLRequest *)request;
+
+@end

Squirrel/SQRLDownloadManager.m

@@ -0,0 +1,239 @@
+//
+//  SQRLDownloadController.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 26/09/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLDownloadManager.h"
+
+#import <ReactiveCocoa/ReactiveCocoa.h>
+
+#import "SQRLDirectoryManager.h"
+#import "SQRLDownload.h"
+#import "SQRLDownload+Private.h"
+#import "SQRLResumableDownload.h"
+
+#import "NSData+SQRLExtensions.h"
+
+@interface SQRLDownloadManager ()
+@property (nonatomic, strong, readonly) SQRLDirectoryManager *directoryManager;
+@property (nonatomic, assign, readonly) dispatch_queue_t queue;
+
+// Reads the download index.
+//
+// Returns a signal which sends the download index at time of read then
+// completes, or errors.
+- (RACSignal *)readDownloadIndex;
+
+// Write a new download index.
+//
+// block - Map from the old download index to the new download index. Writing
+//         is serialised, subsequent writers will receive the output of the
+//         previous map block. If the output of the map is equal to the input
+//         no write is attempted and the returned signal completes.
+//
+// Returns a signal which completes or errors.
+- (RACSignal *)writeDownloadIndexWithBlock:(NSDictionary * (^)(NSMutableDictionary *))block;
+@end
+
+@implementation SQRLDownloadManager
+
++ (instancetype)defaultDownloadManager {
+	static SQRLDownloadManager *defaultDownloadManager;
+	static dispatch_once_t defaultDownloadManagerPredicate;
+
+	dispatch_once(&defaultDownloadManagerPredicate, ^{
+		defaultDownloadManager = [[self alloc] initWithDirectoryManager:SQRLDirectoryManager.currentApplicationManager];
+	});
+
+	return defaultDownloadManager;
+}
+
+- (id)initWithDirectoryManager:(SQRLDirectoryManager *)directoryManager {
+	NSParameterAssert(directoryManager != nil);
+
+	self = [super init];
+	if (self == nil) return nil;
+
+	_directoryManager = directoryManager;
+
+	_queue = dispatch_queue_create("com.github.Squirrel.SQRLDownloadManager.queue", DISPATCH_QUEUE_CONCURRENT);
+	dispatch_set_target_queue(_queue, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0));
+
+	return self;
+}
+
+- (void)dealloc {
+	if (_queue != NULL) dispatch_release(_queue);
+}
+
+- (RACSignal *)removeAllResumableDownloads {
+	return [[[RACSignal
+		merge:@[
+			[self downloadStoreIndexFileLocation],
+			[self.directoryManager downloadDirectoryURL]
+		]]
+		flattenMap:^ (NSURL *location) {
+			return [[RACSignal
+				defer:^{
+					NSError *error;
+					BOOL remove = [NSFileManager.defaultManager removeItemAtURL:location error:&error];
+					return (remove ? [RACSignal empty] : [RACSignal error:error]);
+				}]
+				catch:^(NSError *error) {
+					if ([error.domain isEqualToString:NSCocoaErrorDomain] && error.code == NSFileNoSuchFileError) return [RACSignal empty];
+					return [RACSignal error:error];
+				}];
+		}]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+- (RACSignal *)downloadStoreIndexFileLocation {
+	return [[[self.directoryManager
+		applicationSupportURL]
+		map:^(NSURL *directory) {
+			return [directory URLByAppendingPathComponent:@"DownloadIndex.plist"];
+		}]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+- (RACSignal *)readDownloadIndex {
+	return [[[self
+		downloadStoreIndexFileLocation]
+		flattenMap:^(NSURL *location) {
+			return [RACSignal
+				create:^(id<RACSubscriber> subscriber) {
+					dispatch_async(self.queue, ^{
+						if (subscriber.disposable.disposed) return;
+
+						NSError *error;
+						NSDictionary *propertyList = [self readPropertyListWithContentsOfURL:location error:&error];
+						if (propertyList == nil) {
+							[subscriber sendError:error];
+							return;
+						}
+
+						[subscriber sendNext:propertyList];
+						[subscriber sendCompleted];
+					});
+				}];
+		}]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+- (RACSignal *)writeDownloadIndexWithBlock:(NSDictionary * (^)(NSMutableDictionary *))block {
+	NSParameterAssert(block != nil);
+
+	return [[[self
+		downloadStoreIndexFileLocation]
+		flattenMap:^(NSURL *location) {
+			return [RACSignal create:^(id<RACSubscriber> subscriber) {
+				dispatch_barrier_async(self.queue, ^{
+					if (subscriber.disposable.disposed) return;
+
+					NSError *error;
+					NSDictionary *propertyList = [self readPropertyListWithContentsOfURL:location error:&error];
+					if (propertyList == nil) {
+						[subscriber sendError:error];
+						return;
+					}
+
+					NSDictionary *newPropertyList = block([propertyList mutableCopy]);
+					if ([newPropertyList isEqual:propertyList]) {
+						[subscriber sendCompleted];
+						return;
+					}
+
+					NSData *newData = [NSKeyedArchiver archivedDataWithRootObject:newPropertyList];
+					if (newData == nil) {
+						NSDictionary *errorInfo = @{ NSURLErrorKey: location };
+						[subscriber sendError:[NSError errorWithDomain:NSCocoaErrorDomain code:NSPropertyListWriteStreamError userInfo:errorInfo]];
+						return;
+					}
+
+					BOOL write = [newData writeToURL:location options:NSDataWritingAtomic error:&error];
+					if (!write) {
+						[subscriber sendError:error];
+						return;
+					}
+
+					[subscriber sendCompleted];
+				});
+			}];
+		}]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+- (NSDictionary *)readPropertyListWithContentsOfURL:(NSURL *)location error:(NSError **)errorRef {
+	NSData *propertyListData = [NSData dataWithContentsOfURL:location options:NSDataReadingUncached error:NULL];
+	if (propertyListData == nil) {
+		return @{};
+	}
+
+	NSDictionary *propertyList = [NSKeyedUnarchiver unarchiveObjectWithData:propertyListData];
+	if (propertyList == nil) {
+		if (errorRef != NULL) {
+			NSDictionary *errorInfo = @{ NSURLErrorKey: location };
+			*errorRef = [NSError errorWithDomain:NSCocoaErrorDomain code:NSPropertyListReadCorruptError userInfo:errorInfo];
+		}
+		return nil;
+	}
+
+	return propertyList;
+}
+
++ (NSString *)keyForURL:(NSURL *)URL {
+	return URL.absoluteString;
+}
+
++ (NSString *)fileNameForURL:(NSURL *)URL {
+	NSString *key = [self keyForURL:URL];
+	return [[[key dataUsingEncoding:NSUTF8StringEncoding] sqrl_SHA1Hash] sqrl_base16String];
+}
+
+- (RACSignal *)downloadForRequest:(NSURLRequest *)request {
+	NSParameterAssert(request != nil);
+
+	return [[[[self
+		readDownloadIndex]
+		map:^(NSDictionary *index) {
+			NSString *key = [self.class keyForURL:request.URL];
+			return index[key];
+		}]
+		flattenMap:^(SQRLResumableDownload *download) {
+			if (download != nil) return [RACSignal return:download];
+
+			return [[[self.directoryManager
+				downloadDirectoryURL]
+				map:^(NSURL *downloadDirectory) {
+					return [downloadDirectory URLByAppendingPathComponent:[self.class fileNameForURL:request.URL]];
+				}]
+				map:^(NSURL *location) {
+					return [[SQRLDownload alloc] initWithRequest:request fileURL:location];
+				}];
+		}]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+- (RACSignal *)setDownload:(SQRLResumableDownload *)download forRequest:(NSURLRequest *)request {
+	NSParameterAssert(download.response != nil);
+	NSParameterAssert(request != nil);
+
+	return [[self
+		writeDownloadIndexWithBlock:^(NSMutableDictionary *index) {
+			NSString *key = [self.class keyForURL:request.URL];
+
+			if (download != nil) {
+				index[key] = download;
+			} else {
+				[index removeObjectForKey:key];
+			}
+
+			return index;
+		}]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+@end

Squirrel/SQRLDownloadedUpdate.h

@@ -11,7 +11,7 @@
 @class SQRLUpdate;
 
 // A SQRLUpdate that has been successfully downloaded to disk.
-@interface SQRLDownloadedUpdate : MTLModel
+@interface SQRLDownloadedUpdate : MTLModel <MTLJSONSerializing>
 
 // The application bundle representing the downloaded and unarchived update.
 @property (nonatomic, strong, readonly) NSBundle *bundle;

Squirrel/SQRLDownloadedUpdate.m

@@ -7,6 +7,7 @@
 //
 
 #import "SQRLDownloadedUpdate.h"
+#import "SQRLUpdate.h"
 #import <ReactiveCocoa/ReactiveCocoa.h>
 
 @interface SQRLDownloadedUpdate ()
@@ -40,9 +41,15 @@
 #pragma mark MTLJSONSerializing
 
 + (NSDictionary *)JSONKeyPathsByPropertyKey {
-	return @{
-		@keypath(SQRLDownloadedUpdate.new, bundleURL): NSNull.null
-	};
+	return @{};
+}
+
++ (NSValueTransformer *)updateJSONTransformer {
+	return [MTLValueTransformer mtl_JSONDictionaryTransformerWithModelClass:SQRLUpdate.class];
+}
+
++ (NSValueTransformer *)bundleURLJSONTransformer {
+	return [NSValueTransformer valueTransformerForName:MTLURLValueTransformerName];
 }
 
 @end

Squirrel/SQRLInstaller+Private.h

@@ -1,17 +0,0 @@
-//
-//  SQRLInstaller+Private.h
-//  Squirrel
-//
-//  Created by Keith Duncan on 08/01/2014.
-//  Copyright (c) 2014 GitHub. All rights reserved.
-//
-
-#import "SQRLInstaller.h"
-
-// The defaults key to store a `SQRLInstallerOwnedBundle` so that a moved bundle
-// can be restored.
-extern NSString * const SQRLInstallerOwnedBundleKey;
-
-// The defaults key to store the number of installation attempts that have been
-// made.
-extern NSString * const SQRLShipItInstallationAttemptsKey;

Squirrel/SQRLInstaller.h

@@ -11,7 +11,7 @@
 // The domain for errors originating within SQRLInstaller.
 extern NSString * const SQRLInstallerErrorDomain;
 
-// There was an error copying the target or update bundle to a backup location.
+// There was an error copying the target bundle to the backup location.
 extern const NSInteger SQRLInstallerErrorBackupFailed;
 
 // There was an error replacing the target bundle with the update.
@@ -34,39 +34,35 @@ extern const NSInteger SQRLInstallerErrorInvalidState;
 // There was an error moving a bundle across volumes.
 extern const NSInteger SQRLInstallerErrorMovingAcrossVolumes;
 
-// There was an error changing the file permissions of the update.
-extern const NSInteger SQRLInstallerErrorChangingPermissions;
+@class RACSignal;
+@class RACAction;
+@class SQRLShipItState;
+@class SQRLDirectoryManager;
 
-@class RACCommand;
-
-// Performs the installation of an update, saving its intermediate state to user
-// defaults.
+// Performs the installation of an update, using the `SQRLShipItState` on disk,
+// as located by `SQRLDirectoryManager`.
 //
 // This class is meant to be used only after the app that will be updated has
 // terminated.
 @interface SQRLInstaller : NSObject
 
-// Initializes an installer using the given application identifier, which is
-// used to scope resumable state stored to user defaults.
+// Attempts to install the update or resume an in-progress installation.
 //
-// applicationIdentifier - The defaults domain in which to store resumable
-//                         state. Must not be nil.
-- (instancetype)initWithApplicationIdentifier:(NSString *)applicationIdentifier;
-
-// When executed with a `SQRLShipItRequest`, attempts to install the update or
-// resume an in-progress installation.
-//
-// Each execution will complete or error on an unspecified scheduler when
+// Returns a signal which completes or errors on an unspecified scheduler when
 // installation has completed or failed.
-@property (nonatomic, strong, readonly) RACCommand *installUpdateCommand;
+- (RACSignal *)installUpdateWithState:(SQRLShipItState *)state;
 
-// When executed with a `SQRLShipItRequest`, aborts an installation, and
-// attempts to restore the old version of the application if necessary.
+// Aborts an installation, and attempts to restore the old version of the
+// application if necessary.
 //
-// This must not be executed while `installUpdateCommand` is executing.
+// This must not be executed while `installUpdateWithState:` is executing.
 //
-// Each execution will complete or error on an unspecified scheduler once
+// Returns a signal while completes or errors on an unspecified scheduler once
 // aborting/recovery has finished.
-@property (nonatomic, strong, readonly) RACCommand *abortInstallationCommand;
+- (RACSignal *)abortInstallationWithState:(SQRLShipItState *)state;
+
+// Initializes an installer using the given directory manager to read and write the
+// state of the installation.
+- (id)initWithDirectoryManager:(SQRLDirectoryManager *)directoryManager;
 
 @end

Squirrel/SQRLInstaller.m

@@ -7,24 +7,17 @@
 //
 
 #import "SQRLInstaller.h"
-
-#import <libkern/OSAtomic.h>
-#import "EXTScope.h"
-#import <ReactiveCocoa/NSEnumerator+RACSequenceAdditions.h>
-#import <ReactiveCocoa/NSObject+RACPropertySubscribing.h>
-#import <ReactiveCocoa/RACCommand.h>
-#import <ReactiveCocoa/RACSequence.h>
-#import <ReactiveCocoa/RACSignal+Operations.h>
-#import <ReactiveCocoa/RACSubscriber.h>
-#import <sys/xattr.h>
-
 #import "NSBundle+SQRLVersionExtensions.h"
 #import "NSError+SQRLVerbosityExtensions.h"
 #import "RACSignal+SQRLTransactionExtensions.h"
 #import "SQRLCodeSignature.h"
-#import "SQRLShipItRequest.h"
+#import "SQRLDirectoryManager.h"
+#import "SQRLShipItState.h"
 #import "SQRLTerminationListener.h"
-#import "SQRLInstallerOwnedBundle.h"
+#import <libkern/OSAtomic.h>
+#import <ReactiveCocoa/EXTScope.h>
+#import <ReactiveCocoa/ReactiveCocoa.h>
+#import <sys/xattr.h>
 
 NSString * const SQRLInstallerErrorDomain = @"SQRLInstallerErrorDomain";
 
@@ -35,58 +28,85 @@ const NSInteger SQRLInstallerErrorInvalidBundleVersion = -4;
 const NSInteger SQRLInstallerErrorMissingInstallationData = -5;
 const NSInteger SQRLInstallerErrorInvalidState = -6;
 const NSInteger SQRLInstallerErrorMovingAcrossVolumes = -7;
-const NSInteger SQRLInstallerErrorChangingPermissions = -8;
 
-NSString * const SQRLShipItInstallationAttemptsKey = @"SQRLShipItInstallationAttempts";
-NSString * const SQRLInstallerOwnedBundleKey = @"SQRLInstallerOwnedBundle";
+// Maps an installer state to a selector to invoke.
+typedef struct {
+	// The state for which the associated method should be invoked.
+	SQRLInstallerState installerState;
+
+	// A method accepting a `SQRLShipItState` argument and returning a cold
+	// signal.
+	//
+	// If NULL, installation should complete.
+	SEL selector;
+} SQRLInstallerDispatchTableEntry;
 
 @interface SQRLInstaller ()
 
-// The defaults domain to store all resumable state in.
-@property (nonatomic, copy, readonly) NSString *applicationIdentifier;
+// Finds the state file to read and write from.
+@property (nonatomic, strong, readonly) SQRLDirectoryManager *directoryManager;
 
-// The bundle currently owned by this installer.
+// Reads the given key from `state`, failing if it's not set.
 //
-// Stores the bundle moved aside by an install request so that the original
-// bundle can be restored to its original location if needed.
-@property (atomic, strong) SQRLInstallerOwnedBundle *ownedBundle;
-
-// Reads the given key from `request`, failing if it's not set.
-//
-// key     - The property key to read from `request`. This must not be nil, and
-//           should refer to a property of object type.
-// request - The request object to read. This must not be nil.
+// key   - The property key to read from `state`. This must not be nil, and
+//         should refer to a property of object type.
+// state - The state object to read. This must not be nil.
 //
 // Returns a signal which synchronously sends the non-nil read value then
 // completes, or errors.
-- (RACSignal *)getRequiredKey:(NSString *)key fromRequest:(SQRLShipItRequest *)request;
+- (RACSignal *)getRequiredKey:(NSString *)key fromState:(SQRLShipItState *)state;
 
-// Moves the updateBundleURL to an owned directory to prevent symlink attack,
-// takes user:group ownership of the bundle, then verifies that it meets the
-// designated requirement of the targetBundleURL.
+// Performs the remaining stages of installation, as specified by `state`.
 //
-// request - The request whose update should be prepared and validated.
+// state - The installation state. This must not be nil.
 //
-// Returns a signal which sends the owned & validated bundle URL then completes,
-// or errors.
-- (RACSignal *)prepareAndValidateUpdateBundleURLForRequest:(SQRLShipItRequest *)request;
+// Returns a signal which will complete or error on an unspecified thread.
+- (RACSignal *)resumeInstallationFromState:(SQRLShipItState *)state;
 
-// Saves a `SQRLInstallerOwnedBundle` for the targetBundleURL to the
-// preferences, then moves the targetBundleURL to an owned directory.
+// Moves the specified bundle to a backup location.
 //
-// request - The request whose target should be removed in preparation of an
-//           update being installed.
+// bundleURL - The URL to the bundle that should be backed up. This must not be
+//             nil.
 //
-// Returns a signal which completes, or errors.
-- (RACSignal *)acquireTargetBundleURLForRequest:(SQRLShipItRequest *)request;
+// Returns a signal which will send the `NSURL` to the proposed backup location
+// as soon as possible, then complete once the bundle has actually been moved.
+- (RACSignal *)backUpBundleAtURL:(NSURL *)bundleURL;
 
-// Deletes a bundle that was moved into place using -moveAndTakeOwnershipOfBundleAtURL:.
+// Deletes a bundle that was backed up using -backUpBundleAtURL:.
 //
-// bundleURL - The URL to the backup bundle, as sent from -moveAndTakeOwnershipOfBundleAtURL:.
+// backupURL - The URL to the backup bundle, as sent from -backUpBundleAtURL:.
 //             This must not be nil.
 //
 // Returns a signal which will synchronously complete or error.
-- (RACSignal *)deleteOwnedBundleAtURL:(NSURL *)bundleURL;
+- (RACSignal *)deleteBackupAtURL:(NSURL *)backupURL;
+
+// Validates the code signature of a bundle, optionally restoring it upon
+// failure.
+//
+// bundleURL       - The URL of the bundle whose code signature should be
+//                   verified. This must not be nil.
+// signature       - The code signature that the bundle must match. This must
+//                   not be nil.
+// backupBundleURL - If not nil, the URL to a bundle that should replace
+//                   `bundleURL` if the code signature does not pass validation.
+//
+// Returns a signal which will synchronously complete if `bundleURL` passes
+// validation, or if the bundle was recovered from `backupBundleURL`. If
+// validation or recovery fails, an error will be sent.
+- (RACSignal *)verifyBundleAtURL:(NSURL *)bundleURL usingSignature:(SQRLCodeSignature *)signature recoveringUsingBackupAtURL:(NSURL *)backupBundleURL;
+
+// Attempts to determine whether a bundle has already been moved on disk.
+//
+// sourceURL - The original URL to the bundle. This must not be nil.
+// targetURL - The proposed destination URL for the bundle. This must not be
+//             nil.
+// signature - The code signature that any item must match in order to be
+//             considered the correct bundle. This must not be nil.
+//
+// Returns a signal which will synchronously send YES if `targetURL` points to
+// a bundle matching the code signature, NO if it doesn't and `sourceURL` still
+// exists, or an error otherwise.
+- (RACSignal *)checkWhetherBundlePreviouslyAtURL:(NSURL *)sourceURL wasInstalledAtURL:(NSURL *)targetURL usingSignature:(SQRLCodeSignature *)signature;
 
 // Moves `sourceURL` to `targetURL`.
 //
@@ -98,7 +118,7 @@ NSString * const SQRLInstallerOwnedBundleKey = @"SQRLInstallerOwnedBundle";
 // sourceURL - The URL to move from. This must not be nil.
 //
 // Retruns a signal which will synchronously complete or error.
-- (RACSignal *)installItemToURL:(NSURL *)targetURL fromURL:(NSURL *)sourceURL;
+- (RACSignal *)installItemAtURL:(NSURL *)targetURL fromURL:(NSURL *)sourceURL;
 
 // Recursively clears the quarantine extended attribute from the given
 // directory.
@@ -112,96 +132,56 @@ NSString * const SQRLInstallerOwnedBundleKey = @"SQRLInstallerOwnedBundle";
 // Returns a signal which will send completed or error on a background thread.
 - (RACSignal *)clearQuarantineForDirectory:(NSURL *)directory;
 
-// Recursively changes the owner and group of the given directory tree to that
-// of the current process, then disables writing for anyone but the owner.
-//
-// directoryURL - The URL to the folder to take ownership of. This must not be
-//                nil.
-//
-// Returns a signal which will synchronously complete or error.
-- (RACSignal *)takeOwnershipOfDirectory:(NSURL *)directoryURL;
-
 @end
 
 @implementation SQRLInstaller
 
 #pragma mark Lifecycle
 
-- (id)initWithApplicationIdentifier:(NSString *)applicationIdentifier {
-	NSParameterAssert(applicationIdentifier != nil);
+- (id)initWithDirectoryManager:(SQRLDirectoryManager *)directoryManager {
+	NSParameterAssert(directoryManager != nil);
 
 	self = [super init];
 	if (self == nil) return nil;
 
-	_applicationIdentifier = [applicationIdentifier copy];
-
-	@weakify(self);
-
-	RACSignal *aborting = [[[[RACObserve(self, abortInstallationCommand)
-		ignore:nil]
-		map:^(RACCommand *command) {
-			return command.executing;
-		}]
-		switchToLatest]
-		setNameWithFormat:@"aborting"];
-
-	_installUpdateCommand = [[RACCommand alloc] initWithEnabled:[aborting not] signalBlock:^(SQRLShipItRequest *request) {
-		@strongify(self);
-		NSParameterAssert(request != nil);
-
-		// Request can be changed between launches, the installer may have
-		// already have an owned bundle, for a previous targetURL.
-		//
-		// If that's the case, we need to abort the previous owned bundle, and
-		// then handle the new install request.
-
-		return [[[[self
-			abortInstall]
-			doError:^(NSError *error) {
-				NSLog(@"Couldn't abort install and restore owned bundle to previous location %@, error %@", self.ownedBundle.originalURL, error.sqrl_verboseDescription);
-			}]
-			catchTo:[RACSignal empty]]
-			then:^{
-				return [self installRequest:request];
-			}];
-	}];
-
-	_abortInstallationCommand = [[RACCommand alloc] initWithEnabled:[self.installUpdateCommand.executing not] signalBlock:^(SQRLShipItRequest *request) {
-		@strongify(self);
-
-		return [self abortInstall];
-	}];
-
+	_directoryManager = directoryManager;
+	
 	return self;
 }
 
-#pragma mark Preferences
+#pragma mark Actions
 
-- (SQRLInstallerOwnedBundle *)ownedBundle {
-	id archiveData = CFBridgingRelease(CFPreferencesCopyValue((__bridge CFStringRef)SQRLInstallerOwnedBundleKey, (__bridge CFStringRef)self.applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost));
-	if (![archiveData isKindOfClass:NSData.class]) return nil;
+- (RACSignal *)installUpdateWithState:(SQRLShipItState *)state {
+	NSParameterAssert(state != nil);
 
-	SQRLInstallerOwnedBundle *ownedBundle = [NSKeyedUnarchiver unarchiveObjectWithData:archiveData];
-	if (![ownedBundle isKindOfClass:SQRLInstallerOwnedBundle.class]) return nil;
-
-	return ownedBundle;
+	return [[self
+		resumeInstallationFromState:state]
+		sqrl_addTransactionWithName:NSLocalizedString(@"Updating", nil) description:NSLocalizedString(@"%@ is being updated, and interrupting the process could corrupt the application", nil), state.targetBundleURL.path];
 }
 
-- (void)setOwnedBundle:(SQRLInstallerOwnedBundle *)ownedBundle {
-	NSData *archiveData = (ownedBundle == nil ? nil : [NSKeyedArchiver archivedDataWithRootObject:ownedBundle]);
-	CFPreferencesSetValue((__bridge CFStringRef)SQRLInstallerOwnedBundleKey, (__bridge CFPropertyListRef)archiveData, (__bridge CFStringRef)self.applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
-	CFPreferencesSynchronize((__bridge CFStringRef)self.applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
+- (RACSignal *)abortInstallationWithState:(SQRLShipItState *)state {
+	NSParameterAssert(state != nil);
+
+	return [[[RACSignal
+		zip:@[
+			[self getRequiredKey:@keypath(state.targetBundleURL) fromState:state],
+			[self getRequiredKey:@keypath(state.codeSignature) fromState:state]
+		] reduce:^(NSURL *targetBundleURL, SQRLCodeSignature *codeSignature) {
+			return [self verifyBundleAtURL:targetBundleURL usingSignature:codeSignature recoveringUsingBackupAtURL:state.backupBundleURL];
+		}]
+		flatten]
+		sqrl_addTransactionWithName:NSLocalizedString(@"Aborting update", nil) description:NSLocalizedString(@"An update to %@ is being rolled back, and interrupting the process could corrupt the application", nil), state.targetBundleURL.path];
 }
 
-#pragma mark Properties
+#pragma mark Installer State
 
-- (RACSignal *)getRequiredKey:(NSString *)key fromRequest:(SQRLShipItRequest *)request {
+- (RACSignal *)getRequiredKey:(NSString *)key fromState:(SQRLShipItState *)state {
 	NSParameterAssert(key != nil);
-	NSParameterAssert(request != nil);
+	NSParameterAssert(state != nil);
 
 	return [[RACSignal
 		defer:^{
-			id value = [request valueForKey:key];
+			id value = [state valueForKey:key];
 			if (value == nil) {
 				NSString *errorDescription = [NSString stringWithFormat:NSLocalizedString(@"Missing %@", nil), key];
 				return [RACSignal error:[self missingDataErrorWithDescription:errorDescription]];
@@ -209,275 +189,309 @@ NSString * const SQRLInstallerOwnedBundleKey = @"SQRLInstallerOwnedBundle";
 				return [RACSignal return:value];
 			}
 		}]
-		setNameWithFormat:@"%@ -getRequiredKey: %@ fromRequest: %@", self, key, request];
+		setNameWithFormat:@"%@ -getRequiredKey: %@ fromState: %@", self, key, state];
 }
 
-#pragma mark Installer States
+- (RACSignal *)resumeInstallationFromState:(SQRLShipItState *)state {
+	NSParameterAssert(state != nil);
 
-- (RACSignal *)prepareAndValidateUpdateBundleURLForRequest:(SQRLShipItRequest *)request {
-	NSParameterAssert(request != nil);
+	const SQRLInstallerDispatchTableEntry dispatchTablePrototype[] = {
+		{ .installerState = SQRLInstallerStateNothingToDo, .selector = NULL },
+		{ .installerState = SQRLInstallerStateClearingQuarantine, .selector = @selector(clearQuarantineWithState:) },
+		{ .installerState = SQRLInstallerStateBackingUp, .selector = @selector(backUpWithState:) },
+		{ .installerState = SQRLInstallerStateInstalling, .selector = @selector(installWithState:) },
+		{ .installerState = SQRLInstallerStateVerifyingInPlace, .selector = @selector(verifyInPlaceWithState:) },
+	};
 
-	return [[[[[[[self
-		ownedTemporaryDirectoryURL]
-		flattenMap:^(NSURL *directoryURL) {
-			return [self copyBundleAtURL:request.updateBundleURL toDirectory:directoryURL];
-		}]
+	const size_t tableCount = sizeof(dispatchTablePrototype) / sizeof(*dispatchTablePrototype);
+	NSValue *boxedDispatchTable = [NSValue valueWithBytes:dispatchTablePrototype objCType:@encode(__typeof__(dispatchTablePrototype))];
+
+	RACSignal *step = [RACSignal defer:^{
+		SQRLInstallerDispatchTableEntry dispatchTable[tableCount];
+		[boxedDispatchTable getValue:&dispatchTable];
+
+		SQRLInstallerState installerState = state.installerState;
+
+		size_t tableIndex;
+		for (tableIndex = 0; tableIndex < tableCount; tableIndex++) {
+			if (dispatchTable[tableIndex].installerState == installerState) {
+				break;
+			}
+		}
+
+		if (tableIndex >= tableCount) {
+			NSDictionary *userInfo = @{
+				NSLocalizedDescriptionKey: [NSString stringWithFormat:NSLocalizedString(@"Invalid installer state %i", nil), (int)installerState],
+				NSLocalizedRecoverySuggestionErrorKey: NSLocalizedString(@"Try installing the update again.", nil)
+			};
+
+			return [RACSignal error:[NSError errorWithDomain:SQRLInstallerErrorDomain code:SQRLInstallerErrorInvalidState userInfo:userInfo]];
+		}
+
+		SEL selector = dispatchTable[tableIndex].selector;
+		if (selector == NULL) {
+			// Nothing to do.
+			return [RACSignal empty];
+		}
+
+		NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:[self methodSignatureForSelector:selector]];
+		invocation.target = self;
+		invocation.selector = selector;
+		
+		SQRLShipItState *stateArg = state;
+		[invocation setArgument:&stateArg atIndex:2];
+		[invocation invoke];
+
+		__unsafe_unretained RACSignal *step = nil;
+		[invocation getReturnValue:&step];
+
+		SQRLInstallerState nextState;
+		if (tableIndex + 1 >= tableCount) {
+			nextState = SQRLInstallerStateNothingToDo;
+		} else {
+			nextState = dispatchTable[tableIndex + 1].installerState;
+		}
+
+		return [[[step
+			doCompleted:^{
+				NSLog(@"Completed state %i", (int)installerState);
+			}]
+			ignoreValues]
+			concat:[RACSignal return:@(nextState)]];
+	}];
+
+	return [[self
+		stepRepeatedly:step withState:state]
+		setNameWithFormat:@"%@ -resumeInstallationFromState: %@", self, state];
+}
+
+- (RACSignal *)stepRepeatedly:(RACSignal *)step withState:(SQRLShipItState *)state {
+	NSParameterAssert(step != nil);
+	NSParameterAssert(state != nil);
+
+	return [step flattenMap:^(NSNumber *nextState) {
+		state.installerState = nextState.integerValue;
+		state.installationStateAttempt = 1;
+		return [[state
+			writeUsingURL:self.directoryManager.shipItStateURL]
+			// Automatically begin the next step.
+			concat:[self stepRepeatedly:step withState:state]];
+	}];
+}
+
+- (RACSignal *)clearQuarantineWithState:(SQRLShipItState *)state {
+	NSParameterAssert(state != nil);
+
+	return [[[self
+		getRequiredKey:@keypath(state.updateBundleURL) fromState:state]
 		flattenMap:^(NSURL *bundleURL) {
-			return [[[self
-				clearQuarantineForDirectory:bundleURL]
-				ignoreValues]
-				concat:[RACSignal return:bundleURL]];
+			return [self clearQuarantineForDirectory:bundleURL];
 		}]
-		zipWith:[self codeSignatureForBundleAtURL:request.targetBundleURL]]
-		reduceEach:^(NSURL *updateBundleURL, SQRLCodeSignature *codeSignature) {
-			return [[[self
-				verifyBundleAtURL:updateBundleURL usingSignature:codeSignature]
-				ignoreValues]
-				concat:[RACSignal return:updateBundleURL]];
-		}]
-		flatten]
-		setNameWithFormat:@"%@ -prepareAndValidateUpdateBundleURLForRequest: %@", self, request];
+		setNameWithFormat:@"%@ -clearQuarantineWithState: %@", self, state];
 }
 
-- (RACSignal *)acquireTargetBundleURLForRequest:(SQRLShipItRequest *)request {
-	NSParameterAssert(request != nil);
+- (RACSignal *)backUpWithState:(SQRLShipItState *)state {
+	NSParameterAssert(state != nil);
 
 	return [[[[RACSignal
 		zip:@[
-			[self ownedTemporaryDirectoryURL],
-			[self codeSignatureForBundleAtURL:request.targetBundleURL],
-		] reduce:^(NSURL *directoryURL, SQRLCodeSignature *codeSignature) {
-			NSURL *targetBundleURL = request.targetBundleURL;
-			NSURL *newBundleURL = [directoryURL URLByAppendingPathComponent:targetBundleURL.lastPathComponent];
+			[self getRequiredKey:@keypath(state.targetBundleURL) fromState:state],
+			[self getRequiredKey:@keypath(state.codeSignature) fromState:state],
+		] reduce:^(NSURL *bundleURL, SQRLCodeSignature *codeSignature) {
+			RACSignal *skipBackup = [RACSignal return:@NO];
+			if (state.backupBundleURL != nil) {
+				skipBackup = [self checkWhetherBundlePreviouslyAtURL:bundleURL wasInstalledAtURL:state.backupBundleURL usingSignature:codeSignature];
+			}
 
-			return [[SQRLInstallerOwnedBundle alloc] initWithOriginalURL:request.targetBundleURL temporaryURL:newBundleURL codeSignature:codeSignature];
+			return [skipBackup flattenMap:^(NSNumber *skip) {
+				if (skip.boolValue) {
+					return [RACSignal empty];
+				} else {
+					return [self backUpBundleAtURL:bundleURL];
+				}
+			}];
 		}]
-		doNext:^(SQRLInstallerOwnedBundle *ownedBundle) {
-			self.ownedBundle = ownedBundle;
+		flatten]
+		flattenMap:^(NSURL *backupBundleURL) {
+			// Save the chosen backup URL as soon as we have it, so we
+			// can resume even if the state change hasn't taken effect.
+			//
+			// N.B. It's important that this method remain
+			// synchronous, so it finishes before returning
+			// control to -backUpBundleAtURL:. Really, the flow
+			// here should be refactored so it doesn't matter.
+			state.backupBundleURL = backupBundleURL;
+			return [state writeUsingURL:self.directoryManager.shipItStateURL];
 		}]
-		flattenMap:^(SQRLInstallerOwnedBundle *ownedBundle) {
-			return [self installItemToURL:ownedBundle.temporaryURL fromURL:ownedBundle.originalURL];
-		}]
-		setNameWithFormat:@"%@ -acquireTargetBundleURLForRequest: %@", self, request];
+		setNameWithFormat:@"%@ -backUpWithState: %@", self, state];
 }
 
-- (RACSignal *)renameIfNeeded:(SQRLShipItRequest *)request updateBundleURL:(NSURL *)updateBundleURL {
-	if (!request.useUpdateBundleName) return [RACSignal return:request];
+- (RACSignal *)installWithState:(SQRLShipItState *)state {
+	NSParameterAssert(state != nil);
 
-	return [[self
-		renamedTargetIfNeededWithTargetURL:request.targetBundleURL sourceURL:updateBundleURL]
-		flattenMap:^(NSURL *newTargetURL) {
-			if ([newTargetURL isEqual:request.targetBundleURL]) return [RACSignal return:request];
-
-			SQRLShipItRequest *updatedRequest = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:request.updateBundleURL targetBundleURL:newTargetURL bundleIdentifier:request.bundleIdentifier launchAfterInstallation:request.launchAfterInstallation useUpdateBundleName:request.useUpdateBundleName];
-			return [[self
-				installItemToURL:newTargetURL fromURL:request.targetBundleURL]
-				concat:[RACSignal return:updatedRequest]];
-		}];
-}
-
-- (RACSignal *)installRequest:(SQRLShipItRequest *)request {
-	NSParameterAssert(request != nil);
-
-	return [[[[self
-		prepareAndValidateUpdateBundleURLForRequest:request]
-		flattenMap:^(NSURL *updateBundleURL) {
+	return [[[RACSignal
+		zip:@[
+			[self getRequiredKey:@keypath(state.targetBundleURL) fromState:state],
+			[self getRequiredKey:@keypath(state.updateBundleURL) fromState:state],
+			[self getRequiredKey:@keypath(state.backupBundleURL) fromState:state],
+			[self getRequiredKey:@keypath(state.codeSignature) fromState:state]
+		] reduce:^(NSURL *targetBundleURL, NSURL *updateBundleURL, NSURL *backupBundleURL, SQRLCodeSignature *codeSignature) {
 			return [[[[self
-				renameIfNeeded:request updateBundleURL:updateBundleURL]
-				flattenMap:^(SQRLShipItRequest *request) {
-					return [[self acquireTargetBundleURLForRequest:request] concat:[RACSignal return:request]];
+				checkWhetherBundlePreviouslyAtURL:updateBundleURL wasInstalledAtURL:targetBundleURL usingSignature:codeSignature]
+				flattenMap:^(NSNumber *skip) {
+					if (skip.boolValue) {
+						return [RACSignal empty];
+					} else {
+						return [self installItemAtURL:targetBundleURL fromURL:updateBundleURL];
+					}
 				}]
-				flattenMap:^(SQRLShipItRequest *request) {
-					return [[[[[[self
-						installItemToURL:request.targetBundleURL fromURL:updateBundleURL]
-						concat:[RACSignal return:request.updateBundleURL]]
-						concat:[RACSignal return:updateBundleURL]]
-						concat:[RACSignal defer:^{
-							return [RACSignal return:self.ownedBundle.temporaryURL];
-						}]]
-						flattenMap:^(NSURL *location) {
-							return [[[self
-								deleteOwnedBundleAtURL:location]
-								doError:^(NSError *error) {
-									NSLog(@"Couldn't remove owned bundle at location %@, error %@", location, error.sqrl_verboseDescription);
-								}]
-								catchTo:[RACSignal empty]];
-						}]
-						concat:[RACSignal return:request]];
+				catch:^(NSError *error) {
+					NSString *description = [NSString stringWithFormat:NSLocalizedString(@"Failed to replace bundle %@ with update %@", nil), targetBundleURL, updateBundleURL];
+					return [RACSignal error:[self errorByAddingDescription:description code:SQRLInstallerErrorReplacingTarget toError:error]];
 				}]
-				doCompleted:^{
-					self.ownedBundle = nil;
+				catch:^(NSError *error) {
+					// Verify that the target bundle didn't get corrupted during
+					// failure. Try recovering it if it did.
+					return [[self
+						verifyBundleAtURL:targetBundleURL usingSignature:codeSignature recoveringUsingBackupAtURL:backupBundleURL]
+						// Recovery succeeded, but we still want to pass
+						// through the original error.
+						concat:[RACSignal error:error]];
 				}];
 		}]
-		sqrl_addTransactionWithName:NSLocalizedString(@"Updating", nil) description:NSLocalizedString(@"%@ is being updated, and interrupting the process could corrupt the application", nil), request.targetBundleURL.path]
-		setNameWithFormat:@"%@ -installRequest: %@", self, request];
+		flatten]
+		setNameWithFormat:@"%@ -installWithState: %@", self, state];
 }
 
-- (RACSignal *)abortInstall {
-	// The request may have been tampered with to select a new targetURL to
-	// which the moved bundles should be restored.
-	//
-	// Discard the request parameters and restore the owned bundle to its
-	// original location.
-
-	SQRLInstallerOwnedBundle *ownedBundle = self.ownedBundle;
-	if (ownedBundle == nil) return [RACSignal empty];
-
-	return [[[[self
-		installItemToURL:ownedBundle.originalURL fromURL:ownedBundle.temporaryURL]
-		doCompleted:^{
-			self.ownedBundle = nil;
-		}]
-		sqrl_addTransactionWithName:NSLocalizedString(@"Aborting update", nil) description:NSLocalizedString(@"An update to %@ is being rolled back, and interrupting the process could corrupt the application", nil), ownedBundle.originalURL.path]
-		setNameWithFormat:@"%@ -abortInstall", self];
-}
-
-#pragma mark Bundle Ownership
-
-- (RACSignal *)ownedTemporaryDirectoryURL {
-	return [[[RACSignal
-		defer:^{
-			NSString *tmpPath = [NSTemporaryDirectory() stringByResolvingSymlinksInPath];
-			NSString *template = [NSString stringWithFormat:@"%@.XXXXXXXX", self.applicationIdentifier];
-
-			char *fullTemplate = strdup([tmpPath stringByAppendingPathComponent:template].UTF8String);
-			@onExit {
-				free(fullTemplate);
-			};
-
-			if (mkdtemp(fullTemplate) == NULL) {
-				return [RACSignal error:[NSError errorWithDomain:NSPOSIXErrorDomain code:errno userInfo:nil]];
-			}
-
-			NSURL *URL = [NSURL fileURLWithPath:[NSFileManager.defaultManager stringWithFileSystemRepresentation:fullTemplate length:strlen(fullTemplate)] isDirectory:YES];
-			return [RACSignal return:URL];
-		}]
-		catch:^(NSError *error) {
-			NSString *description = [NSString stringWithFormat:NSLocalizedString(@"Could not create temporary folder", nil)];
-			return [RACSignal error:[self errorByAddingDescription:description code:SQRLInstallerErrorBackupFailed toError:error]];
-		}]
-		setNameWithFormat:@"%@ -ownedDirectoryURL", self];
-}
-
-- (RACSignal *)copyBundleAtURL:(NSURL *)bundleURL toDirectory:(NSURL *)directoryURL {
-	NSParameterAssert(bundleURL != nil);
-	NSParameterAssert(directoryURL != nil);
-
-	NSURL *newBundleURL = [directoryURL URLByAppendingPathComponent:bundleURL.lastPathComponent];
+- (RACSignal *)verifyInPlaceWithState:(SQRLShipItState *)state {
+	NSParameterAssert(state != nil);
 
 	return [[[RACSignal
-		defer:^{
-			NSError *error;
-			BOOL copy = [NSFileManager.defaultManager copyItemAtURL:bundleURL toURL:newBundleURL error:&error];
-			if (!copy) return [RACSignal error:error];
-
-			return [RACSignal return:newBundleURL];
+		zip:@[
+			[self getRequiredKey:@keypath(state.targetBundleURL) fromState:state],
+			[self getRequiredKey:@keypath(state.backupBundleURL) fromState:state],
+			[self getRequiredKey:@keypath(state.codeSignature) fromState:state]
+		] reduce:^(NSURL *targetBundleURL, NSURL *backupBundleURL, SQRLCodeSignature *codeSignature) {
+			return [[self
+				verifyBundleAtURL:targetBundleURL usingSignature:codeSignature recoveringUsingBackupAtURL:backupBundleURL]
+				concat:[[self
+					deleteBackupAtURL:backupBundleURL]
+					catchTo:[RACSignal empty]]];
 		}]
-		catch:^(NSError *error) {
-			NSString *description = [NSString stringWithFormat:NSLocalizedString(@"Failed to copy bundle %@ to directory %@", nil), bundleURL, newBundleURL];
-			return [RACSignal error:[self errorByAddingDescription:description code:SQRLInstallerErrorBackupFailed toError:error]];
-		}]
-		setNameWithFormat:@"%@ -copyBundleAtURL: %@ toDirectory: %@", self, bundleURL, directoryURL];
+		flatten]
+		setNameWithFormat:@"%@ -verifyInPlaceWithState: %@", self, state];
 }
 
-- (RACSignal *)deleteOwnedBundleAtURL:(NSURL *)bundleURL {
-	NSParameterAssert(bundleURL != nil);
+#pragma mark Backing Up
 
-	return [[[RACSignal
-		defer:^{
-			NSError *error;
-			if ([NSFileManager.defaultManager removeItemAtURL:bundleURL error:&error]) {
-				return [RACSignal empty];
-			} else {
+- (RACSignal *)backUpBundleAtURL:(NSURL *)targetBundleURL {
+	NSParameterAssert(targetBundleURL != nil);
+
+	return [[[[[[self.directoryManager
+		applicationSupportURL]
+		flattenMap:^(NSURL *applicationSupportURL) {
+			NSError *error = nil;
+			NSURL *temporaryDirectoryURL = [NSFileManager.defaultManager URLForDirectory:NSItemReplacementDirectory inDomain:NSUserDomainMask appropriateForURL:applicationSupportURL create:YES error:&error];
+			if (temporaryDirectoryURL == nil) {
 				return [RACSignal error:error];
 			}
+
+			return [RACSignal return:temporaryDirectoryURL];
 		}]
-		then:^{
+		catch:^(NSError *error) {
+			NSString *description = [NSString stringWithFormat:NSLocalizedString(@"Could not create backup folder", nil)];
+			return [RACSignal error:[self errorByAddingDescription:description code:SQRLInstallerErrorBackupFailed toError:error]];
+		}]
+		map:^(NSURL *temporaryDirectoryURL) {
+			return [temporaryDirectoryURL URLByAppendingPathComponent:targetBundleURL.lastPathComponent];
+		}]
+		flattenMap:^(NSURL *backupBundleURL) {
+			return [[[[self
+				installItemAtURL:backupBundleURL fromURL:targetBundleURL]
+				catch:^(NSError *error) {
+					NSString *description = [NSString stringWithFormat:NSLocalizedString(@"Failed to move bundle %@ to backup location %@", nil), targetBundleURL, backupBundleURL];
+					return [RACSignal error:[self errorByAddingDescription:description code:SQRLInstallerErrorBackupFailed toError:error]];
+				}]
+				ignoreValues]
+				// Return the backup URL before doing any work, to increase
+				// fault tolerance.
+				startWith:backupBundleURL];
+		}]
+		setNameWithFormat:@"%@ -backUpBundleAtURL: %@", self, targetBundleURL];
+}
+
+- (RACSignal *)deleteBackupAtURL:(NSURL *)backupURL {
+	NSParameterAssert(backupURL != nil);
+
+	return [[RACSignal
+		defer:^{
+			NSError *error = nil;
+			if (![NSFileManager.defaultManager removeItemAtURL:backupURL error:&error]) {
+				return [RACSignal error:error];
+			}
+
 			// Also remove the temporary directory that the backup lived in.
-			NSURL *temporaryDirectoryURL = bundleURL.URLByDeletingLastPathComponent;
+			NSURL *temporaryDirectoryURL = backupURL.URLByDeletingLastPathComponent;
 
 			// However, use rmdir() to skip it in case there are other files
 			// contained within (for whatever reason).
-			if (rmdir(temporaryDirectoryURL.path.fileSystemRepresentation) == 0) {
-				return [RACSignal empty];
-			} else {
-				int code = errno;
-				NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
-
-				const char *desc = strerror(code);
-				if (desc != NULL) {
-					userInfo[NSLocalizedDescriptionKey] = @(desc);
-				} else {
-					userInfo[NSLocalizedDescriptionKey] = NSLocalizedString(@"Unknown POSIX error", @"");
-				}
-
-				userInfo[NSLocalizedFailureReasonErrorKey] = [NSString stringWithFormat:NSLocalizedString(@"Couldn't remove temp dir \"%@\"", @""), temporaryDirectoryURL.path];
-				userInfo[NSURLErrorKey] = temporaryDirectoryURL;
-
-				return [RACSignal error:[NSError errorWithDomain:NSPOSIXErrorDomain code:errno userInfo:userInfo]];
+			if (rmdir(temporaryDirectoryURL.path.fileSystemRepresentation) != 0) {
+				return [RACSignal error:[NSError errorWithDomain:NSPOSIXErrorDomain code:errno userInfo:nil]];
 			}
+
+			return [RACSignal empty];
 		}]
-		setNameWithFormat:@"%@ -deleteOwnedBundleAtURL: %@", self, bundleURL];
+		setNameWithFormat:@"%@ -deleteBackupAtURL: %@", self, backupURL];
 }
 
-#pragma mark Verification
-
-- (RACSignal *)codeSignatureForBundleAtURL:(NSURL *)URL {
-	return [[RACSignal
-		defer:^{
-			NSError *error;
-			SQRLCodeSignature *codeSignature = [SQRLCodeSignature signatureWithBundle:URL error:&error];
-			if (codeSignature == nil) return [RACSignal error:error];
-			return [RACSignal return:codeSignature];
-		}]
-		setNameWithFormat:@"%@ -codeSignatureForBundleAtURL: %@", self, URL];
-}
-
-- (RACSignal *)verifyBundleAtURL:(NSURL *)bundleURL usingSignature:(SQRLCodeSignature *)signature {
+- (RACSignal *)verifyBundleAtURL:(NSURL *)bundleURL usingSignature:(SQRLCodeSignature *)signature recoveringUsingBackupAtURL:(NSURL *)backupBundleURL {
 	NSParameterAssert(bundleURL != nil);
 	NSParameterAssert(signature != nil);
 
-	return [[[self
-		takeOwnershipOfDirectory:bundleURL]
-		then:^{
-			return [signature verifyBundleAtURL:bundleURL];
+	return [[[signature
+		verifyBundleAtURL:bundleURL]
+		catch:^(NSError *error) {
+			if (backupBundleURL == nil) return [RACSignal error:error];
+
+			return [[[RACSignal
+				defer:^{
+					[NSFileManager.defaultManager removeItemAtURL:bundleURL error:NULL];
+
+					return [self installItemAtURL:bundleURL fromURL:backupBundleURL];
+				}]
+				doCompleted:^{
+					NSLog(@"Restored backup bundle to %@", bundleURL);
+				}]
+				doError:^(NSError *recoveryError) {
+					NSLog(@"Could not restore backup bundle %@ to %@: %@", backupBundleURL, bundleURL, recoveryError.sqrl_verboseDescription);
+				}];
 		}]
-		setNameWithFormat:@"%@ -verifyBundleAtURL: %@ usingSignature: %@", self, bundleURL, signature];
+		setNameWithFormat:@"%@ -verifyBundleAtURL: %@ usingSignature: %@ recoveringUsingBackupAtURL: %@", self, bundleURL, signature, backupBundleURL];
 }
 
 #pragma mark Installation
 
-/// Check if the target should be renamed and provide the renamed URL.
-///
-/// targetURL - The URL for the target. Cannot be nil.
-/// sourceURL - The URL for the source. Cannot be nil.
-///
-/// Returns a signal which will send the URL for the renamed target. If a rename
-/// isn't needed then it will send `targetURL`.
-- (RACSignal *)renamedTargetIfNeededWithTargetURL:(NSURL *)targetURL sourceURL:(NSURL *)sourceURL {
-	return [RACSignal defer:^{
-		NSBundle *sourceBundle = [NSBundle bundleWithURL:sourceURL];
-		NSString *targetExecutableName = targetURL.lastPathComponent.stringByDeletingPathExtension;
-		NSString *sourceExecutableName = sourceBundle.sqrl_executableName;
+- (RACSignal *)checkWhetherBundlePreviouslyAtURL:(NSURL *)sourceURL wasInstalledAtURL:(NSURL *)targetURL usingSignature:(SQRLCodeSignature *)signature {
+	NSParameterAssert(targetURL != nil);
+	NSParameterAssert(sourceURL != nil);
+	NSParameterAssert(signature != nil);
 
-		// If they're already the same then we're good.
-		if ([targetExecutableName isEqual:sourceExecutableName]) {
-			return [RACSignal return:targetURL];
-		}
-
-		NSString *newAppName = [sourceExecutableName stringByAppendingPathExtension:@"app"];
-		NSURL *newTargetURL = [targetURL.URLByDeletingLastPathComponent URLByAppendingPathComponent:newAppName];
-
-		// If there's already something there then don't rename to it.
-		if ([NSFileManager.defaultManager fileExistsAtPath:newTargetURL.path]) {
-			return [RACSignal return:targetURL];
-		}
-
-		return [RACSignal return:newTargetURL];
-	}];
+	return [[[[self
+		verifyBundleAtURL:targetURL usingSignature:signature recoveringUsingBackupAtURL:nil]
+		concat:[RACSignal return:@YES]]
+		catch:^(NSError *error) {
+			BOOL directory;
+			if ([NSFileManager.defaultManager fileExistsAtPath:sourceURL.path isDirectory:&directory]) {
+				// If the source still exists, this isn't an error.
+				return [RACSignal return:@NO];
+			} else {
+				return [RACSignal error:error];
+			}
+		}]
+		setNameWithFormat:@"%@ -checkWhetherBundlePreviouslyAtURL: %@ wasInstalledAtURL: %@", self, sourceURL, targetURL];
 }
 
-- (RACSignal *)installItemToURL:(NSURL *)targetURL fromURL:(NSURL *)sourceURL {
+- (RACSignal *)installItemAtURL:(NSURL *)targetURL fromURL:(NSURL *)sourceURL {
 	NSParameterAssert(targetURL != nil);
 	NSParameterAssert(sourceURL != nil);
 
@@ -489,7 +503,7 @@ NSString * const SQRLInstallerOwnedBundleKey = @"SQRLInstallerOwnedBundle";
 			} else {
 				int code = errno;
 				NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
-
+				
 				const char *desc = strerror(code);
 				if (desc != NULL) userInfo[NSLocalizedDescriptionKey] = @(desc);
 
@@ -530,7 +544,7 @@ NSString * const SQRLInstallerOwnedBundleKey = @"SQRLInstallerOwnedBundle";
 				return YES;
 			}];
 
-			return enumerator.rac_sequence.signal;
+			return [enumerator.rac_promise start];
 		}]
 		flattenMap:^(NSURL *URL) {
 			const char *path = URL.path.fileSystemRepresentation;
@@ -541,16 +555,9 @@ NSString * const SQRLInstallerOwnedBundleKey = @"SQRLInstallerOwnedBundle";
 				// file to begin with.
 				if (code != ENOATTR) {
 					NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
-
+					
 					const char *desc = strerror(code);
-					if (desc != NULL) {
-						userInfo[NSLocalizedDescriptionKey] = @(desc);
-					} else {
-						userInfo[NSLocalizedDescriptionKey] = NSLocalizedString(@"Unknown POSIX error", @"");
-					}
-
-					userInfo[NSLocalizedFailureReasonErrorKey] = [NSString stringWithFormat:NSLocalizedString(@"Couldn't remove quarantine attribute from \"%@\". This most likely means the file is read-only.", @""), URL.path];
-					userInfo[NSURLErrorKey] = URL;
+					if (desc != NULL) userInfo[NSLocalizedDescriptionKey] = @(desc);
 
 					return [RACSignal error:[NSError errorWithDomain:NSPOSIXErrorDomain code:code userInfo:userInfo]];
 				}
@@ -561,97 +568,6 @@ NSString * const SQRLInstallerOwnedBundleKey = @"SQRLInstallerOwnedBundle";
 		setNameWithFormat:@"%@ -clearQuarantineForDirectory: %@", self, directory];
 }
 
-#pragma mark File Security
-
-- (RACSignal *)readFileSecurityOfURL:(NSURL *)location {
-	NSParameterAssert(location != nil);
-
-	return [[RACSignal
-		defer:^{
-			NSError *error;
-			NSFileSecurity *fileSecurity;
-			if (![location getResourceValue:&fileSecurity forKey:NSURLFileSecurityKey error:&error]) {
-				return [RACSignal error:error];
-			}
-
-			return [RACSignal return:fileSecurity];
-		}]
-		setNameWithFormat:@"%@ -readFileSecurity: %@", self, location];
-}
-
-- (RACSignal *)writeFileSecurity:(NSFileSecurity *)fileSecurity toURL:(NSURL *)location {
-	NSParameterAssert(location != nil);
-
-	return [[RACSignal
-		defer:^{
-			NSError *error;
-			if (![location setResourceValue:fileSecurity forKey:NSURLFileSecurityKey error:&error]) {
-				return [RACSignal error:error];
-			}
-
-			return [RACSignal empty];
-		}]
-		setNameWithFormat:@"%@ -writeFileSecurity: %@", self, location];
-}
-
-- (RACSignal *)takeOwnershipOfDirectory:(NSURL *)directoryURL {
-	NSParameterAssert(directoryURL != nil);
-
-	return [[[RACSignal
-		createSignal:^(id<RACSubscriber> subscriber) {
-			NSDirectoryEnumerator *enumerator = [NSFileManager.defaultManager enumeratorAtURL:directoryURL includingPropertiesForKeys:@[ NSURLFileSecurityKey ] options:0 errorHandler:^ BOOL (NSURL *url, NSError *error) {
-				[subscriber sendError:error];
-				return NO;
-			}];
-
-			return [[enumerator.rac_sequence.signal
-				startWith:directoryURL]
-				subscribe:subscriber];
-		}]
-		flattenMap:^(NSURL *itemURL) {
-			return [[[self
-				readFileSecurityOfURL:itemURL]
-				flattenMap:^(NSFileSecurity *fileSecurity) {
-					if (![self takeOwnershipOfFileSecurity:fileSecurity]) {
-						NSDictionary *errorInfo = @{
-							NSLocalizedDescriptionKey: NSLocalizedString(@"Permissions Error", nil),
-							NSLocalizedRecoverySuggestionErrorKey: [NSString stringWithFormat:NSLocalizedString(@"Couldn’t update permissions of %@", nil), itemURL.path],
-							NSURLErrorKey: itemURL
-						};
-
-						return [RACSignal error:[NSError errorWithDomain:SQRLInstallerErrorDomain code:SQRLInstallerErrorChangingPermissions userInfo:errorInfo]];
-					}
-
-					return [RACSignal return:fileSecurity];
-				}]
-				flattenMap:^(NSFileSecurity *fileSecurity) {
-					return [self writeFileSecurity:fileSecurity toURL:itemURL];
-				}];
-		}]
-		setNameWithFormat:@"%@ -takeOwnershipOfDirectory: %@", self, directoryURL];
-}
-
-- (BOOL)takeOwnershipOfFileSecurity:(NSFileSecurity *)fileSecurity {
-	CFFileSecurityRef actualFileSecurity = (__bridge CFFileSecurityRef)fileSecurity;
-
-	// If ShipIt is running as root, this will change the owner to
-	// root:wheel.
-	if (!CFFileSecuritySetOwner(actualFileSecurity, getuid())) return NO;
-	if (!CFFileSecuritySetGroup(actualFileSecurity, getgid())) return NO;
-
-	mode_t fileMode = 0;
-	if (!CFFileSecurityGetMode(actualFileSecurity, &fileMode)) return NO;
-
-	// Remove write permission from group and other, leave executable
-	// bit as it was for both.
-	//
-	// Permissions will be r-(x?)r-(x?) afterwards, with owner
-	// permissions left as is.
-	fileMode = (fileMode & ~(S_IWGRP | S_IWOTH));
-
-	return CFFileSecuritySetMode(actualFileSecurity, fileMode);
-}
-
 #pragma mark Error Handling
 
 - (NSError *)missingDataErrorWithDescription:(NSString *)description {

Squirrel/SQRLInstallerOwnedBundle.h

@@ -1,37 +0,0 @@
-//
-//  SQRLInstallerOwnedBundle.h
-//  Squirrel
-//
-//  Created by Keith Duncan on 08/01/2014.
-//  Copyright (c) 2014 GitHub. All rights reserved.
-//
-
-#import <Mantle/Mantle.h>
-
-@class SQRLCodeSignature;
-
-// Tracks original and temporary locations of a bundle. Should be created and
-// serialised before moving a bundle aside.
-//
-// Can be used to ensure new targetURL requests meet the original bundle at that
-// location's code signature, even though it's been moved aside.
-@interface SQRLInstallerOwnedBundle : MTLModel
-
-// Designated initialiser.
-//
-// originalURL   - Where the bundle currently resides, and should be restored to
-//                 should an error occur.
-// temporaryURL  - Where the bundle will be moved to, so that another bundle can
-//                 take its place at originalURL.
-// codeSignature - The code signature of the original bundle, so that the
-//                 signature can be used irrespective of where the bundle
-//                 currently resides.
-//
-// Returns an initialised owned bundle for serializing.
-- (instancetype)initWithOriginalURL:(NSURL *)originalURL temporaryURL:(NSURL *)temporaryURL codeSignature:(SQRLCodeSignature *)codeSignature;
-
-@property (readonly, copy, nonatomic) NSURL *originalURL;
-@property (readonly, copy, nonatomic) NSURL *temporaryURL;
-@property (readonly, copy, nonatomic) SQRLCodeSignature *codeSignature;
-
-@end

Squirrel/SQRLInstallerOwnedBundle.m

@@ -1,23 +0,0 @@
-//
-//  SQRLInstallerOwnedBundle.m
-//  Squirrel
-//
-//  Created by Keith Duncan on 08/01/2014.
-//  Copyright (c) 2014 GitHub. All rights reserved.
-//
-
-#import "SQRLInstallerOwnedBundle.h"
-
-#import "EXTKeyPathCoding.h"
-
-@implementation SQRLInstallerOwnedBundle
-
-- (instancetype)initWithOriginalURL:(NSURL *)originalURL temporaryURL:(NSURL *)temporaryURL codeSignature:(SQRLCodeSignature *)codeSignature {
-	return [self initWithDictionary:@{
-		@keypath(self.originalURL): originalURL,
-		@keypath(self.temporaryURL): temporaryURL,
-		@keypath(self.codeSignature): codeSignature,
-	} error:NULL];
-}
-
-@end

Squirrel/SQRLResumableDownload.h

@@ -0,0 +1,27 @@
+//
+//  SQRLResumableDownload.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 30/09/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+#import "SQRLDownload.h"
+
+// A download which has already been started and already has partial data.
+@interface SQRLResumableDownload : SQRLDownload
+
+// Designated initialiser.
+//
+// request  - See `SQRLDownload`.
+// response - HTTP response whose body is being downloaded to `fileURL`.
+//            Must not be nil.
+// fileURL  - See `SQRLDownload`.
+- (instancetype)initWithRequest:(NSURLRequest *)request response:(NSHTTPURLResponse *)response fileURL:(NSURL *)fileURL;
+
+// The `response` the receiver was initialised with.
+@property (readonly, copy, nonatomic) NSHTTPURLResponse *response;
+
+@end

Squirrel/SQRLResumableDownload.m

@@ -0,0 +1,66 @@
+//
+//  SQRLResumableDownload.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 30/09/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLResumableDownload.h"
+
+#import <ReactiveCocoa/ReactiveCocoa.h>
+
+#import "NSHTTPURLResponse+SQRLExtensions.h"
+
+@implementation SQRLResumableDownload
+
+- (instancetype)initWithRequest:(NSURLRequest *)request response:(NSHTTPURLResponse *)response fileURL:(NSURL *)fileURL {
+	NSParameterAssert(request != nil);
+	NSParameterAssert(response != nil);
+	NSParameterAssert(fileURL != nil);
+
+	return [self initWithDictionary:@{
+		@keypath(self.request): request,
+		@keypath(self.response): response,
+		@keypath(self.fileURL): fileURL,
+	} error:NULL];
+}
+
+- (BOOL)isEqual:(SQRLResumableDownload *)object {
+	if (self == object) return YES;
+	if (![object isKindOfClass:self.class]) return NO;
+
+	if (!(self.response == nil && object.response == nil) && ![self responseEqual:object.response]) return NO;
+	if (![object.fileURL isEqual:self.fileURL]) return NO;
+
+	return YES;
+}
+
+- (BOOL)responseEqual:(NSHTTPURLResponse *)response {
+	if (![response.URL isEqual:self.response.URL]) return NO;
+	if (response.statusCode != self.response.statusCode) return NO;
+	if (![response.allHeaderFields isEqual:self.response.allHeaderFields]) return NO;
+	return YES;
+}
+
+- (RACSignal *)resumableRequest {
+	return [[[super
+		resumableRequest]
+		map:^ NSURLRequest * (NSURLRequest *request) {
+			NSHTTPURLResponse *response = self.response;
+			NSString *ETag = [response sqrl_valueForHTTPHeaderField:@"ETag"];
+			if (ETag == nil) return request;
+
+			NSNumber *alreadyDownloadedSize = nil;
+			BOOL getAlreadyDownloadedSize = [self.fileURL getResourceValue:&alreadyDownloadedSize forKey:NSURLFileSizeKey error:NULL];
+			if (!getAlreadyDownloadedSize) return request;
+
+			NSMutableURLRequest *newRequest = [request mutableCopy];
+			[newRequest setValue:ETag forHTTPHeaderField:@"If-Range"];
+			[newRequest setValue:[NSString stringWithFormat:@"%llu-", alreadyDownloadedSize.unsignedLongLongValue] forHTTPHeaderField:@"Range"];
+			return newRequest;
+		}]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+@end

Squirrel/SQRLShipItLauncher.m

@@ -13,7 +13,6 @@
 #import <Security/Security.h>
 #import <ServiceManagement/ServiceManagement.h>
 #import <launch.h>
-#import "SQRLAuthorization.h"
 
 NSString * const SQRLShipItLauncherErrorDomain = @"SQRLShipItLauncherErrorDomain";
 
@@ -22,7 +21,8 @@ const NSInteger SQRLShipItLauncherErrorCouldNotStartService = 1;
 @implementation SQRLShipItLauncher
 
 + (NSString *)shipItJobLabel {
-	return [SQRLDirectoryManager.currentApplicationManager.applicationIdentifier stringByAppendingString:@".ShipIt"];
+	NSString *currentAppIdentifier = NSBundle.mainBundle.bundleIdentifier ?: [NSString stringWithFormat:@"%@:%d", NSProcessInfo.processInfo.processName, NSProcessInfo.processInfo.processIdentifier];
+	return [currentAppIdentifier stringByAppendingString:@".ShipIt"];
 }
 
 + (RACSignal *)shipItJobDictionary {
@@ -31,13 +31,9 @@ const NSInteger SQRLShipItLauncherErrorCouldNotStartService = 1;
 	return [[[RACSignal
 		defer:^{
 			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:jobLabel];
-			return [RACSignal zip:@[
-				[directoryManager shipItStdoutURL],
-				[directoryManager shipItStderrURL],
-				[directoryManager shipItStateURL]
-			]];
+			return [directoryManager applicationSupportURL];
 		}]
-		reduceEach:^(NSURL *stdoutURL, NSURL *stderrURL, NSURL *shipItStateURL) {
+		map:^(NSURL *appSupportURL) {
 			NSBundle *squirrelBundle = [NSBundle bundleForClass:self.class];
 			NSAssert(squirrelBundle != nil, @"Could not open Squirrel.framework bundle");
 
@@ -60,16 +56,14 @@ const NSInteger SQRLShipItLauncherErrorCouldNotStartService = 1;
 			// Pass in the service name so ShipIt knows how to broadcast itself.
 			[arguments addObject:jobLabel];
 
-			// We need to pass the path to ShipIt rather than having ShipIt
-			// calculate the path itself. This is because ShipIt may run as a
-			// different user if it had to escalate to be able to replace the
-			// bundle.
-			[arguments addObject:shipItStateURL.path];
-
 			jobDict[@(LAUNCH_JOBKEY_PROGRAMARGUMENTS)] = arguments;
-			jobDict[@(LAUNCH_JOBKEY_STANDARDOUTPATH)] = stdoutURL.path;
-			jobDict[@(LAUNCH_JOBKEY_STANDARDERRORPATH)] = stderrURL.path;
+			jobDict[@(LAUNCH_JOBKEY_STANDARDOUTPATH)] = [appSupportURL URLByAppendingPathComponent:@"ShipIt_stdout.log"].path;
+			jobDict[@(LAUNCH_JOBKEY_STANDARDERRORPATH)] = [appSupportURL URLByAppendingPathComponent:@"ShipIt_stderr.log"].path;
 
+			#if DEBUG
+			jobDict[@(LAUNCH_JOBKEY_DEBUG)] = @YES;
+			#endif
+			
 			return jobDict;
 		}]
 		setNameWithFormat:@"+shipItJobDictionary"];
@@ -77,7 +71,7 @@ const NSInteger SQRLShipItLauncherErrorCouldNotStartService = 1;
 
 + (RACSignal *)shipItAuthorization {
 	return [[RACSignal
-		createSignal:^ RACDisposable * (id<RACSubscriber> subscriber) {
+		create:^(id<RACSubscriber> subscriber) {
 			AuthorizationItem rightItems[] = {
 				{
 					.name = kSMRightModifySystemDaemons,
@@ -114,15 +108,16 @@ const NSInteger SQRLShipItLauncherErrorCouldNotStartService = 1;
 
 			AuthorizationRef authorization = NULL;
 			OSStatus authorizationError = AuthorizationCreate(&rights, &environment, kAuthorizationFlagInteractionAllowed | kAuthorizationFlagExtendRights, &authorization);
-
 			if (authorizationError == noErr) {
-				[subscriber sendNext:[[SQRLAuthorization alloc] initWithAuthorization:authorization]];
+				[subscriber sendNext:(__bridge id)authorization];
 				[subscriber sendCompleted];
 			} else {
 				[subscriber sendError:[NSError errorWithDomain:NSOSStatusErrorDomain code:authorizationError userInfo:nil]];
 			}
 
-			return nil;
+			[subscriber.disposable addDisposable:[RACDisposable disposableWithBlock:^{
+				if (authorization != NULL) AuthorizationFree(authorization, kAuthorizationFlagDestroyRights);
+			}]];
 		}]
 		setNameWithFormat:@"+shipItAuthorization"];
 }
@@ -132,13 +127,11 @@ const NSInteger SQRLShipItLauncherErrorCouldNotStartService = 1;
 		zip:@[
 			self.shipItJobDictionary,
 			(privileged ? self.shipItAuthorization : [RACSignal return:nil])
-		] reduce:^(NSDictionary *jobDictionary, SQRLAuthorization *authorizationValue) {
+		] reduce:^(NSDictionary *jobDictionary, id authorization) {
 			CFStringRef domain = (privileged ? kSMDomainSystemLaunchd : kSMDomainUserLaunchd);
 
-			AuthorizationRef authorization = authorizationValue.authorization;
-
 			CFErrorRef cfError;
-			if (!SMJobRemove(domain, (__bridge CFStringRef)self.shipItJobLabel, authorization, true, &cfError)) {
+			if (!SMJobRemove(domain, (__bridge CFStringRef)self.shipItJobLabel, (__bridge AuthorizationRef)authorization, true, &cfError)) {
 				NSError *error = CFBridgingRelease(cfError);
 				cfError = NULL;
 
@@ -147,7 +140,7 @@ const NSInteger SQRLShipItLauncherErrorCouldNotStartService = 1;
 				}
 			}
 
-			if (!SMJobSubmit(domain, (__bridge CFDictionaryRef)jobDictionary, authorization, &cfError)) {
+			if (!SMJobSubmit(domain, (__bridge CFDictionaryRef)jobDictionary, (__bridge AuthorizationRef)authorization, &cfError)) {
 				return [RACSignal error:CFBridgingRelease(cfError)];
 			}
 

Squirrel/SQRLShipItRequest.h

@@ -1,100 +0,0 @@
-//
-//  SQRLShipItRequest.h
-//  Squirrel
-//
-//  Created by Keith Duncan on 08/01/2014.
-//  Copyright (c) 2014 GitHub. All rights reserved.
-//
-
-#import <Mantle/Mantle.h>
-
-@class RACSignal;
-
-// The domain for errors originating within `SQRLShipItRequest`.
-extern NSString * const SQRLShipItRequestErrorDomain;
-
-// Errors originating from the `SQRLShipItRequestErrorDomain`.
-//
-// SQRLShipItRequestErrorMissingRequiredProperty - A required property was `nil`
-//                                                 upon initialization.
-//
-//                                                 The `userInfo` dictionary for
-//                                                 this error will contain
-//                                                 `SQRLShipItStatePropertyErrorKey`.
-//
-// SQRLShipItRequestErrorUnarchiving             - The saved request could not
-//                                                 be unarchived, possibly
-//                                                 because it's invalid.
-//
-// SQRLShipItRequestErrorArchiving               - The request object could not
-//                                                 be archived.
-typedef enum : NSInteger {
-	SQRLShipItRequestErrorMissingRequiredProperty = 1,
-	SQRLShipItRequestErrorUnarchiving = 2,
-	SQRLShipItRequestErrorArchiving = 3,
-} SQRLShipItRequestError;
-
-// Associated with an `NSString` indicating the required property key that did
-// not have a value upon initialization.
-extern NSString * const SQRLShipItRequestPropertyErrorKey;
-
-// Constructed and written to disk for `ShipIt` to pick up. This represents a
-// single update request from the client's perspective.
-@interface SQRLShipItRequest : MTLModel
-
-// Reads a `SQRLShipItState` from disk, at the location specified by the given
-// URL signal.
-//
-// URLSignal - Determines the file location to read from, the signal should send
-//             an `NSURL` object then complete, or error. This must not be nil.
-//
-// Returns a signal which will synchronously send a `SQRLShipItRequest` then
-// complete, or error.
-+ (RACSignal *)readUsingURL:(RACSignal *)URLSignal;
-
-// Writes the receiver to disk, at the location specified by the given URL
-// signal.
-//
-// URLSignal - Determines the file location to write to. The signal should send
-//             an `NSURL` object then complete, or error. This must not be nil.
-//
-// Returns a signal which will synchronously complete or error.
-- (RACSignal *)writeUsingURL:(RACSignal *)URLSignal;
-
-// Designated initialiser.
-//
-// updateBundleURL         - The update bundle which will replace
-//                           targetBundleURL. Must not be nil.
-// targetBundleURL         - Where the update should be installed, if a bundle
-//                           is already present, the update is checked for
-//                           suitability against this bundle. Must not be nil.
-// bundleIdentifier        - The bundle identifier that the installer should
-//                           wait for instances of to terminate before
-//                           installing. Can be nil.
-// launchAfterInstallation - Whether the updated application should be launched
-//                           after installation.
-// useUpdateBundleName     - Should the target use the update bundle's name?
-//
-// Returns a request which can be written to disk for ShipIt to read and
-// perform.
-- (instancetype)initWithUpdateBundleURL:(NSURL *)updateBundleURL targetBundleURL:(NSURL *)targetBundleURL bundleIdentifier:(NSString *)bundleIdentifier launchAfterInstallation:(BOOL)launchAfterInstallation useUpdateBundleName:(BOOL)useUpdateBundleName;
-
-// The URL to the downloaded update's app bundle.
-@property (nonatomic, copy, readonly) NSURL *updateBundleURL;
-
-// The URL to the app bundle that should be replaced with the update.
-@property (nonatomic, copy, readonly) NSURL *targetBundleURL;
-
-// The bundle identifier of the application being updated.
-//
-// If not nil, the installer will wait for applications matching this identifier
-// (and `targetBundleURL`) to terminate before continuing.
-@property (nonatomic, copy, readonly) NSString *bundleIdentifier;
-
-// Whether to launch the application after an update is successfully installed.
-@property (nonatomic, assign, readonly) BOOL launchAfterInstallation;
-
-// Whether the app should use the update bundle's name.
-@property (nonatomic, assign, readonly) BOOL useUpdateBundleName;
-
-@end

Squirrel/SQRLShipItRequest.m

@@ -1,194 +0,0 @@
-//
-//  SQRLShipItRequest.m
-//  Squirrel
-//
-//  Created by Keith Duncan on 08/01/2014.
-//  Copyright (c) 2014 GitHub. All rights reserved.
-//
-
-#import "SQRLShipItRequest.h"
-
-#import "EXTKeyPathCoding.h"
-#import <ReactiveCocoa/RACSignal+Operations.h>
-
-NSString * const SQRLShipItRequestErrorDomain = @"SQRLShipItRequestErrorDomain";
-
-NSString * const SQRLShipItRequestPropertyErrorKey = @"SQRLShipItRequestPropertyErrorKey";
-
-@interface SQRLShipItRequest () <MTLJSONSerializing>
-@end
-
-@implementation SQRLShipItRequest
-
-#pragma mark Lifecycle
-
-- (id)initWithDictionary:(NSDictionary *)dictionary error:(NSError **)error {
-	self = [super initWithDictionary:dictionary error:error];
-	if (self == nil) return nil;
-
-	BOOL (^validateKey)(NSString *) = ^(NSString *key) {
-		if ([self valueForKey:key] != nil) return YES;
-
-		if (error != NULL) {
-			NSDictionary *userInfo = @{
-				NSLocalizedDescriptionKey: NSLocalizedString(@"Missing required value", nil),
-				NSLocalizedRecoverySuggestionErrorKey: [NSString stringWithFormat:NSLocalizedString(@"\"%@\" must not be set to nil.", nil), key]
-			};
-
-			*error = [NSError errorWithDomain:SQRLShipItRequestErrorDomain code:SQRLShipItRequestErrorMissingRequiredProperty userInfo:userInfo];
-		}
-
-		return NO;
-	};
-
-	if (!validateKey(@keypath(self.targetBundleURL))) return nil;
-	if (!validateKey(@keypath(self.updateBundleURL))) return nil;
-
-	return self;
-}
-
-- (instancetype)initWithUpdateBundleURL:(NSURL *)updateBundleURL targetBundleURL:(NSURL *)targetBundleURL bundleIdentifier:(NSString *)bundleIdentifier launchAfterInstallation:(BOOL)launchAfterInstallation useUpdateBundleName:(BOOL)useUpdateBundleName {
-	return [self initWithDictionary:@{
-		@keypath(self.updateBundleURL): updateBundleURL,
-		@keypath(self.targetBundleURL): targetBundleURL,
-		@keypath(self.bundleIdentifier): bundleIdentifier ?: NSNull.null,
-		@keypath(self.launchAfterInstallation): @(launchAfterInstallation),
-		@keypath(self.useUpdateBundleName): @(useUpdateBundleName),
-	} error:NULL];
-}
-
-#pragma mark Serialization
-
-+ (NSDictionary *)JSONKeyPathsByPropertyKey {
-	return @{};
-}
-
-+ (NSValueTransformer *)updateBundleURLJSONTransformer {
-	return [NSValueTransformer valueTransformerForName:MTLURLValueTransformerName];
-}
-
-+ (NSValueTransformer *)targetBundleURLJSONTransformer {
-	return [NSValueTransformer valueTransformerForName:MTLURLValueTransformerName];
-}
-
-+ (RACSignal *)readUsingURL:(RACSignal *)URL {
-	NSParameterAssert(URL != nil);
-
-	return [[[[URL
-		flattenMap:^(NSURL *stateURL) {
-			NSError *error;
-			NSData *data = [self readFromURL:stateURL error:&error];
-			if (data == nil) {
-				return [RACSignal error:error];
-			}
-
-			return [RACSignal return:data];
-		}]
-		flattenMap:^(NSData *data) {
-			return [self readFromData:data];
-		}]
-		catch:^(NSError *error) {
-			NSDictionary *userInfo = @{
-				NSLocalizedDescriptionKey: NSLocalizedString(@"Could not read update request", nil),
-			};
-			if (error != nil) {
-				userInfo = [userInfo mtl_dictionaryByAddingEntriesFromDictionary:@{
-					NSUnderlyingErrorKey: error,
-				}];
-			}
-			return [RACSignal error:[NSError errorWithDomain:SQRLShipItRequestErrorDomain code:SQRLShipItRequestErrorUnarchiving userInfo:userInfo]];
-		}]
-		setNameWithFormat:@"+readUsingURL: %@", URL];
-}
-
-+ (NSData *)readFromURL:(NSURL *)URL error:(NSError **)errorRef {
-	__block NSData *data = nil;
-
-	NSFileCoordinator *coordinator = [[NSFileCoordinator alloc] initWithFilePresenter:nil];
-	[coordinator coordinateReadingItemAtURL:URL options:NSFileCoordinatorReadingWithoutChanges error:errorRef byAccessor:^(NSURL *newURL) {
-		data = [NSData dataWithContentsOfURL:newURL options:NSDataReadingUncached error:errorRef];
-	}];
-
-	return data;
-}
-
-+ (RACSignal *)readFromData:(NSData *)data {
-	return [[RACSignal
-		defer:^{
-			NSError *error;
-			NSDictionary *JSONDictionary = [NSJSONSerialization JSONObjectWithData:data options:0 error:&error];
-			if (JSONDictionary == nil) {
-				return [RACSignal error:error];
-			}
-
-			SQRLShipItRequest *request = [MTLJSONAdapter modelOfClass:SQRLShipItRequest.class fromJSONDictionary:JSONDictionary error:&error];
-			if (request == nil) {
-				return [RACSignal error:error];
-			}
-
-			return [RACSignal return:request];
-
-		}]
-		setNameWithFormat:@"+readFromData: <NSData %p>", data];
-}
-
-- (RACSignal *)writeUsingURL:(RACSignal *)URL {
-	NSParameterAssert(URL != nil);
-
-	return [[[[RACSignal
-		zip:@[
-			URL,
-			[self serialization]
-		] reduce:^(NSURL *stateURL, NSData *data) {
-			NSError *error;
-			BOOL write = [self writeData:data toURL:stateURL error:&error];
-			if (!write) {
-				return [RACSignal error:error];
-			}
-
-			return [RACSignal empty];
-		}]
-		flatten]
-		catch:^(NSError *error) {
-			NSDictionary *userInfo = @{
-				NSLocalizedDescriptionKey: NSLocalizedString(@"Could not write update request", nil),
-				NSLocalizedRecoverySuggestionErrorKey: NSLocalizedString(@"An unknown error occurred while archiving.", nil),
-			};
-			if (error != nil) {
-				userInfo = [userInfo mtl_dictionaryByAddingEntriesFromDictionary:@{
-					NSUnderlyingErrorKey: error,
-				}];
-			}
-			return [RACSignal error:[NSError errorWithDomain:SQRLShipItRequestErrorDomain code:SQRLShipItRequestErrorArchiving userInfo:userInfo]];
-		}]
-		setNameWithFormat:@"%@ -writeUsingURL: %@", self, URL];
-}
-
-- (BOOL)writeData:(NSData *)data toURL:(NSURL *)URL error:(NSError **)errorRef {
-	__block BOOL success = NO;
-
-	NSFileCoordinator *coordinator = [[NSFileCoordinator alloc] initWithFilePresenter:nil];
-	[coordinator coordinateWritingItemAtURL:URL options:0 error:errorRef byAccessor:^(NSURL *newURL) {
-		success = [data writeToURL:newURL options:NSDataWritingAtomic error:errorRef];
-	}];
-
-	return success;
-}
-
-- (RACSignal *)serialization {
-	return [[RACSignal
-		defer:^{
-			NSDictionary *JSONDictionary = [MTLJSONAdapter JSONDictionaryFromModel:self];
-
-			NSError *error;
-			NSData *data = [NSJSONSerialization dataWithJSONObject:JSONDictionary options:0 error:&error];
-			if (data == nil) {
-				return [RACSignal error:error];
-			}
-
-			return [RACSignal return:data];
-		}]
-		setNameWithFormat:@"%@ serialization", self];
-}
-
-@end

Squirrel/SQRLShipItState.h

@@ -0,0 +1,117 @@
+//
+//  SQRLShipItState.h
+//  Squirrel
+//
+//  Created by Justin Spahr-Summers on 2013-10-08.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import <Mantle/Mantle.h>
+
+// The domain for errors originating within `SQRLShipItState`.
+extern NSString * const SQRLShipItStateErrorDomain;
+
+// A required property was `nil` upon initialization.
+//
+// The `userInfo` dictionary for this error will contain
+// `SQRLShipItStatePropertyErrorKey`.
+extern const NSInteger SQRLShipItStateErrorMissingRequiredProperty;
+
+// The saved state on disk could not be unarchived, possibly because it's
+// invalid.
+extern const NSInteger SQRLShipItStateErrorUnarchiving;
+
+// The state object could not be archived.
+extern const NSInteger SQRLShipItStateErrorArchiving;
+
+// Associated with an NSString indicating the required property key that did not
+// have a value upon initialization.
+extern NSString * const SQRLShipItStatePropertyErrorKey;
+
+// The current state of the installer, for persistence across relaunches and for
+// tolerance of system failures.
+//
+// SQRLInstallerStateNothingToDo        - ShipIt has not started installing yet.
+// SQRLInstallerStateClearingQuarantine - Clearing the quarantine flag on the
+//                                        update bundle so it can used without
+//                                        issue.
+// SQRLInstallerStateBackingUp          - Backing up the target bundle so it can
+//                                        be restored in the event of failure.
+// SQRLInstallerStateInstalling         - Replacing the target bundle with the
+//                                        update bundle.
+// SQRLInstallerStateVerifyingInPlace   - Verifying that the target bundle is
+//                                        still valid after updating.
+//
+// Note that these values must remain backwards compatible, so ShipIt doesn't
+// start up in a weird mode on a newer version.
+typedef enum : NSInteger {
+	SQRLInstallerStateNothingToDo = 0,
+	SQRLInstallerStateClearingQuarantine,
+	SQRLInstallerStateBackingUp,
+	SQRLInstallerStateInstalling,
+	SQRLInstallerStateVerifyingInPlace,
+} SQRLInstallerState;
+
+@class RACSignal;
+@class SQRLCodeSignature;
+
+// Encapsulates all the state needed by the ShipIt process.
+@interface SQRLShipItState : MTLModel
+
+// Reads a `SQRLShipItState` from disk, at the location specified by the given
+// URL signal.
+//
+// URLSignal - Determines the file location to read from, the signal should send
+//             an `NSURL` object then complete, or error. This must not be nil.
+//
+// Returns a signal which will synchronously send a `SQRLShipItState` then
+// complete, or error.
++ (RACSignal *)readUsingURL:(RACSignal *)URL;
+
+// Initializes the receiver with the arguments that will not change during
+// installation.
+- (id)initWithTargetBundleURL:(NSURL *)targetBundleURL updateBundleURL:(NSURL *)updateBundleURL bundleIdentifier:(NSString *)bundleIdentifier codeSignature:(SQRLCodeSignature *)codeSignature;
+
+// Writes the receiver to disk, at the location specified by the given URL
+// signal.
+//
+// URL - Determines the file location to write to. The signal should send an
+//       `NSURL` object then complete, or error. This must not be nil.
+//
+// Returns a signal which will synchronously complete or error.
+- (RACSignal *)writeUsingURL:(RACSignal *)URL;
+
+// The URL to the app bundle that should be replaced with an update.
+@property (nonatomic, copy, readonly) NSURL *targetBundleURL;
+
+// The URL to the downloaded update's app bundle.
+@property (nonatomic, copy, readonly) NSURL *updateBundleURL;
+
+// A code signature that the update bundle must match in order to be valid.
+@property (nonatomic, copy, readonly) SQRLCodeSignature *codeSignature;
+
+// The bundle identifier of the application being updated.
+//
+// If not nil, the installer will wait for applications matching this identifier
+// (and `targetBundleURL`) to terminate before continuing.
+@property (nonatomic, copy, readonly) NSString *bundleIdentifier;
+
+// The current state of the installer.
+@property (atomic, assign) SQRLInstallerState installerState;
+
+// The number of installation attempts that have occurred for the current
+// `state`.
+@property (atomic, assign) NSUInteger installationStateAttempt;
+
+// Whether to relaunch the application after an update is successfully
+// installed.
+@property (atomic, assign) BOOL relaunchAfterInstallation;
+
+// The URL where the target bundle has been backed up to before installing the
+// update.
+//
+// This property is set automatically during the course of installation. It
+// should not be preset.
+@property (atomic, copy) NSURL *backupBundleURL;
+
+@end

Squirrel/SQRLShipItState.m

@@ -0,0 +1,122 @@
+//
+//  SQRLShipItState.m
+//  Squirrel
+//
+//  Created by Justin Spahr-Summers on 2013-10-08.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLShipItState.h"
+#import <ReactiveCocoa/ReactiveCocoa.h>
+
+NSString * const SQRLShipItStateErrorDomain = @"SQRLShipItStateErrorDomain";
+NSString * const SQRLShipItStatePropertyErrorKey = @"SQRLShipItStatePropertyErrorKey";
+
+const NSInteger SQRLShipItStateErrorMissingRequiredProperty = 1;
+const NSInteger SQRLShipItStateErrorUnarchiving = 2;
+const NSInteger SQRLShipItStateErrorArchiving = 3;
+
+@implementation SQRLShipItState
+
+#pragma mark Lifecycle
+
+- (id)initWithDictionary:(NSDictionary *)dictionary error:(NSError **)error {
+	self = [super initWithDictionary:dictionary error:error];
+	if (self == nil) return nil;
+
+	BOOL (^validateKey)(NSString *) = ^(NSString *key) {
+		if ([self valueForKey:key] != nil) return YES;
+
+		if (error != NULL) {
+			NSDictionary *userInfo = @{
+				NSLocalizedDescriptionKey: NSLocalizedString(@"Missing required value", nil),
+				NSLocalizedRecoverySuggestionErrorKey: [NSString stringWithFormat:NSLocalizedString(@"\"%@\" must not be set to nil.", nil), key]
+			};
+
+			*error = [NSError errorWithDomain:SQRLShipItStateErrorDomain code:SQRLShipItStateErrorMissingRequiredProperty userInfo:userInfo];
+		}
+
+		return NO;
+	};
+
+	if (!validateKey(@keypath(self.targetBundleURL))) return nil;
+	if (!validateKey(@keypath(self.updateBundleURL))) return nil;
+	if (!validateKey(@keypath(self.codeSignature))) return nil;
+
+	return self;
+}
+
+- (id)initWithTargetBundleURL:(NSURL *)targetBundleURL updateBundleURL:(NSURL *)updateBundleURL bundleIdentifier:(NSString *)bundleIdentifier codeSignature:(SQRLCodeSignature *)codeSignature {
+	return [self initWithDictionary:@{
+		@keypath(self.targetBundleURL): targetBundleURL,
+		@keypath(self.updateBundleURL): updateBundleURL,
+		@keypath(self.bundleIdentifier): bundleIdentifier ?: NSNull.null,
+		@keypath(self.codeSignature): codeSignature,
+	} error:NULL];
+}
+
+#pragma mark Serialization
+
++ (RACSignal *)readUsingURL:(RACSignal *)URL {
+	NSParameterAssert(URL != nil);
+
+	return [[[URL
+		flattenMap:^(NSURL *stateURL) {
+			NSError *error = nil;
+			NSData *data = [NSData dataWithContentsOfURL:stateURL options:NSDataReadingUncached error:&error];
+			if (data == nil) {
+				return [RACSignal error:error];
+			}
+
+			return [RACSignal return:data];
+		}]
+		flattenMap:^(NSData *data) {
+			SQRLShipItState *state = [NSKeyedUnarchiver unarchiveObjectWithData:data];
+			if (![state isKindOfClass:SQRLShipItState.class]) {
+				NSDictionary *userInfo = @{
+					NSLocalizedDescriptionKey: NSLocalizedString(@"Could not read saved state", nil),
+					NSLocalizedRecoverySuggestionErrorKey: NSLocalizedString(@"An unknown error occurred while unarchiving.", nil)
+				};
+
+				return [RACSignal error:[NSError errorWithDomain:SQRLShipItStateErrorDomain code:SQRLShipItStateErrorUnarchiving userInfo:userInfo]];
+			}
+
+			return [RACSignal return:state];
+		}]
+		setNameWithFormat:@"+readUsingURL: %@", URL];
+}
+
+- (RACSignal *)writeUsingURL:(RACSignal *)URL {
+	NSParameterAssert(URL != nil);
+
+	RACSignal *serialization = [RACSignal defer:^{
+		NSData *data = [NSKeyedArchiver archivedDataWithRootObject:self];
+		if (data == nil) {
+			NSDictionary *userInfo = @{
+				NSLocalizedDescriptionKey: NSLocalizedString(@"Could not save state", nil),
+				NSLocalizedRecoverySuggestionErrorKey: NSLocalizedString(@"An unknown error occurred while archiving.", nil)
+			};
+
+			return [RACSignal error:[NSError errorWithDomain:SQRLShipItStateErrorDomain code:SQRLShipItStateErrorArchiving userInfo:userInfo]];
+		}
+
+		return [RACSignal return:data];
+	}];
+
+	return [[[RACSignal
+		zip:@[
+			URL,
+			serialization
+		] reduce:^(NSURL *stateURL, NSData *data) {
+			NSError *error = nil;
+			if (![data writeToURL:stateURL options:NSDataWritingAtomic error:&error]) {
+				return [RACSignal error:error];
+			}
+
+			return [RACSignal empty];
+		}]
+		flatten]
+		setNameWithFormat:@"%@ -writeUsingURL: %@", self, URL];
+}
+
+@end

Squirrel/SQRLTerminationListener.h

@@ -6,7 +6,7 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Cocoa/Cocoa.h>
+#import <Foundation/Foundation.h>
 
 @class RACSignal;
 

Squirrel/SQRLTerminationListener.m

@@ -7,14 +7,7 @@
 //
 
 #import "SQRLTerminationListener.h"
-
-#import "EXTKeyPathCoding.h"
-#import <ReactiveCocoa/NSArray+RACSequenceAdditions.h>
-#import <ReactiveCocoa/RACDisposable.h>
-#import <ReactiveCocoa/RACScheduler.h>
-#import <ReactiveCocoa/RACSequence.h>
-#import <ReactiveCocoa/RACSignal+Operations.h>
-#import <ReactiveCocoa/RACSubscriber.h>
+#import <ReactiveCocoa/ReactiveCocoa.h>
 
 @interface SQRLTerminationListener ()
 
@@ -52,7 +45,7 @@
 	return [[[[RACSignal
 		defer:^{
 			NSArray *apps = [NSRunningApplication runningApplicationsWithBundleIdentifier:self.bundleIdentifier];
-			return [apps.rac_sequence signalWithScheduler:RACScheduler.immediateScheduler];
+			return apps.rac_signal;
 		}]
 		filter:^(NSRunningApplication *application) {
 			return [application.bundleURL.URLByStandardizingPath isEqual:self.bundleURL];
@@ -67,7 +60,7 @@
 
 - (RACSignal *)waitForTerminationOfProcessIdentifier:(pid_t)processIdentifier {
 	return [[RACSignal
-		createSignal:^(id<RACSubscriber> subscriber) {
+		create:^(id<RACSubscriber> subscriber) {
 			dispatch_source_t source = dispatch_source_create(DISPATCH_SOURCE_TYPE_PROC, processIdentifier, DISPATCH_PROC_EXIT, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0));
 
 			dispatch_source_set_registration_handler(source, ^{
@@ -79,9 +72,10 @@
 			});
 
 			dispatch_resume(source);
-			return [RACDisposable disposableWithBlock:^{
+			[subscriber.disposable addDisposable:[RACDisposable disposableWithBlock:^{
 				dispatch_source_cancel(source);
-			}];
+				dispatch_release(source);
+			}]];
 		}]
 		setNameWithFormat:@"%@ -waitForTerminationOfProcessIdentifier: %i", self, (int)processIdentifier];
 }

Squirrel/SQRLURLConnection.h

@@ -0,0 +1,49 @@
+//
+//  SQRLURLConnection.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 25/09/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+@class SQRLDownloadManager;
+@class RACSignal;
+
+// Resumably download a remote resource.
+//
+// If the resource has previously been downloaded this operation may return the
+// URL of an existing file, contingent on the server matching the ETag of the
+// original response.
+@interface SQRLURLConnection : NSObject
+
+// This is the designated initialiser. The body of the response is streamed to
+// disk. If the response includes an ETag the download can be resumed
+// automatically by subsequent download operations initialised with a request of
+// equal URL.
+//
+// request - Must not be nil, the request is issued with NSURLConnection.
+- (instancetype)initWithRequest:(NSURLRequest *)request __attribute__((nonnull (1)));
+
+// Starts accumulating the resource body in memory, cancels when the
+// subscription is disposed.
+//
+// Returns a signal when sends a tuple of `NSURLResponse` and `NSData`, then
+// completes or errors.
+- (RACSignal *)retrieve;
+
+// Starts downloading the resource body to disk, resuming from a previous
+// download if possible, cancels when the subscription is disposed.
+//
+// downloadManager - Must be non nil, determines where the downloads will be
+//                   stored and resumed from. For a previously started download
+//                   to be resumed, an equivalent download manager should be
+//                   provided.
+//
+// Returns a signal which sends a tuple of `NSURLResponse` and a file
+// scheme `NSURL` where the resource has been stored on disk, then completes, or
+// errors.
+- (RACSignal *)download:(SQRLDownloadManager *)downloadManager __attribute__((nonnull (1)));
+
+@end

Squirrel/SQRLURLConnection.m

@@ -0,0 +1,257 @@
+//
+//  SQRLURLConnection.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 25/09/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLURLConnection.h"
+
+#import <ReactiveCocoa/ReactiveCocoa.h>
+#import <ReactiveCocoa/EXTScope.h>
+
+#import "SQRLDownloadManager.h"
+#import "SQRLResumableDownload.h"
+
+@interface SQRLURLConnection ()
+// The request the downloader was initialised with.
+@property (nonatomic, copy, readonly) NSURLRequest *request;
+
+// Listens for invocations of `selector` on the receiver.
+//
+// The first argument of `selector` must be an `NSURLConnection` object.
+//
+// Returns a signal which sends the _second_ argument of `selector`, or
+// RACUnit if there is only one argument, then completes when the receiver
+// deallocates.
+- (RACSignal *)signalForDelegateSelector:(SEL)selector;
+
+// Subscribes to the connection delegate selectors and starts a connection for
+// `request`.
+//
+// request - The request to perform, must not be nil.
+// mapData - For each response, map the data received for that response to a
+//           result.
+//
+// Returns a signal which sends a tuple of the last response, and the first
+// value from the last `mapData`, then completes, or errors.
+- (RACSignal *)connectionSignalWithRequest:(NSURLRequest *)request mapData:(RACSignal * (^)(NSURLResponse *, RACSignal *))mapData;
+
+@end
+
+@implementation SQRLURLConnection
+
+- (instancetype)initWithRequest:(NSURLRequest *)request {
+	NSParameterAssert(request != nil);
+
+	self = [self init];
+	if (self == nil) return nil;
+
+	_request = [request copy];
+
+	return self;
+}
+
+- (RACSignal *)signalForDelegateSelector:(SEL)selector {
+	NSParameterAssert(selector != NULL);
+
+	return [[self
+		rac_signalForSelector:selector]
+		map:^(RACTuple *args) {
+			return args[1] ?: RACUnit.defaultUnit;
+		}];
+}
+
+- (RACSignal *)connectionSignalWithRequest:(NSURLRequest *)request mapData:(RACSignal * (^)(NSURLResponse *, RACSignal *))mapData {
+	return [[RACSignal
+		create:^(id<RACSubscriber> subscriber) {
+			// A signal that will error if the connection fails for any reason.
+			RACSignal *errors = [[self
+				signalForDelegateSelector:@selector(connection:didFailWithError:)]
+				flattenMap:^(NSError *error) {
+					return [RACSignal error:error];
+				}];
+
+			// Sends (or replays) RACUnit when the connection has finished
+			// loading successfully.
+			RACSignal *finished = [[[[self
+				signalForDelegateSelector:@selector(connectionDidFinishLoading:)]
+				take:1]
+				promiseOnScheduler:RACScheduler.immediateScheduler]
+				start];
+
+			// A signal of all `NSURLResponse`s received on the connection.
+			RACSignal *responses = [[self
+				signalForDelegateSelector:@selector(connection:didReceiveResponse:)]
+				takeUntil:finished];
+
+			// A signal of all `NSData` received on the connection.
+			RACSignal *data = [[self
+				signalForDelegateSelector:@selector(connection:didReceiveData:)]
+				takeUntil:finished];
+
+			[[[[[RACSignal
+				merge:@[ responses, errors ]]
+				takeUntil:finished]
+				map:^(NSURLResponse *response) {
+					return [RACSignal
+						zip:@[
+							[RACSignal return:response],
+							mapData(response, data),
+						]];
+				}]
+				switchToLatest]
+				subscribe:subscriber];
+
+			NSOperationQueue *delegateQueue = [[NSOperationQueue alloc] init];
+			delegateQueue.maxConcurrentOperationCount = 1;
+
+			NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self startImmediately:NO];
+			connection.delegateQueue = delegateQueue;
+
+			[connection start];
+
+			[subscriber.disposable addDisposable:[RACDisposable disposableWithBlock:^{
+				[connection cancel];
+			}]];
+		}]
+		setNameWithFormat:@"%@ %s %@", self, sel_getName(_cmd), request];
+}
+
+#pragma mark Download
+
+- (RACSignal *)truncateDownload:(SQRLDownload *)download {
+	NSParameterAssert(download != nil);
+
+	return [[[[RACSignal
+		defer:^{
+			NSError *error = nil;
+			BOOL remove = [NSFileManager.defaultManager removeItemAtURL:download.fileURL error:&error];
+			return (remove ? [RACSignal empty] : [RACSignal error:error]);
+		}]
+		catch:^(NSError *error) {
+			if ([error.domain isEqualToString:NSCocoaErrorDomain] && error.code == NSFileNoSuchFileError) return [RACSignal empty];
+			return [RACSignal error:error];
+		}]
+		concat:[RACSignal return:download]]
+		setNameWithFormat:@"%@ %s %@", self, sel_getName(_cmd), download];
+}
+
+- (RACSignal *)recordDownload:(SQRLResumableDownload *)download downloadManager:(SQRLDownloadManager *)downloadManager {
+	NSParameterAssert(download != nil);
+	NSParameterAssert(downloadManager != nil);
+
+	return [[[downloadManager
+		setDownload:download forRequest:self.request]
+		concat:[RACSignal return:download]]
+		setNameWithFormat:@"%@ %s %@", self, sel_getName(_cmd), download];
+}
+
+- (RACSignal *)prepareDownload:(SQRLDownload *)download downloadManager:(SQRLDownloadManager *)downloadManager forResponse:(NSURLResponse *)response {
+	return [[RACSignal
+		defer:^{
+			if (![response isKindOfClass:NSHTTPURLResponse.class]) {
+				return [self truncateDownload:download];
+			}
+
+			NSHTTPURLResponse *httpResponse = (id)response;
+
+			RACSignal *downloadSignal;
+			if (httpResponse.statusCode != 206 /* Partial Data */) {
+				downloadSignal = [self truncateDownload:download];
+			} else {
+				downloadSignal = [RACSignal empty];
+			}
+
+			SQRLResumableDownload *newDownload = [[SQRLResumableDownload alloc] initWithRequest:self.request response:httpResponse fileURL:download.fileURL];
+
+			return [[downloadSignal
+				ignoreValues]
+				concat:[self recordDownload:newDownload downloadManager:downloadManager]];
+		}]
+		setNameWithFormat:@"%@ %s %@", self, sel_getName(_cmd), response];
+}
+
+- (BOOL)appendData:(NSData *)data toURL:(NSURL *)fileURL error:(NSError **)errorRef {
+	NSOutputStream *outputStream = [NSOutputStream outputStreamWithURL:fileURL append:YES];
+
+	[outputStream open];
+	@onExit {
+		[outputStream close];
+	};
+
+	uint8_t const *bytes = data.bytes;
+	size_t length = data.length;
+	while (length > 0) {
+		NSInteger written = [outputStream write:bytes maxLength:length];
+		if (written == -1) {
+			NSError *streamError = outputStream.streamError;
+			if ([streamError.domain isEqualToString:NSPOSIXErrorDomain] && streamError.code == EINTR) continue;
+
+			if (errorRef != NULL) *errorRef = streamError;
+			return NO;
+		}
+		
+		bytes += written;
+		length -= written;
+	}
+
+	return YES;
+}
+
+#pragma mark Start
+
+- (RACSignal *)retrieve {
+	return [[self
+		connectionSignalWithRequest:self.request mapData:^(id _, RACSignal *data) {
+			return [data
+				aggregateWithStart:[NSMutableData data] reduce:^(NSMutableData *running, NSData *data) {
+					[running appendData:data];
+					return running;
+				}];
+		}]
+		setNameWithFormat:@"%@ %s", self, sel_getName(_cmd)];
+}
+
+- (RACSignal *)download:(SQRLDownloadManager *)downloadManager {
+	NSParameterAssert(downloadManager != nil);
+
+	RACSignal *download = [[[downloadManager
+		downloadForRequest:self.request]
+		promiseOnScheduler:RACScheduler.immediateScheduler]
+		deferred];
+
+	return [[[download
+		flattenMap:^(SQRLDownload *download) {
+			return [download resumableRequest];
+		}]
+		flattenMap:^(NSURLRequest *request) {
+			return [self connectionSignalWithRequest:request mapData:^(NSURLResponse *response, RACSignal *data) {
+				RACSignal *downloadURL = [[[[download
+					flattenMap:^(SQRLDownload *download) {
+						return [self prepareDownload:download downloadManager:downloadManager forResponse:response];
+					}]
+					map:^(SQRLDownload *download) {
+						return download.fileURL;
+					}]
+					promiseOnScheduler:RACScheduler.immediateScheduler]
+					deferred];
+
+				return [[[[data
+					map:^(NSData *bodyData) {
+						return [[downloadURL
+							try:^(NSURL *fileURL, NSError **errorRef) {
+								return [self appendData:bodyData toURL:fileURL error:errorRef];
+							}]
+							ignoreValues];
+					}]
+					concat]
+					ignoreValues]
+					concat:downloadURL];
+			}];
+		}]
+		setNameWithFormat:@"%@ download: %@", self, downloadManager];
+}
+
+@end

Squirrel/SQRLUpdate.m

@@ -14,6 +14,8 @@ NSString * const SQRLUpdateJSONReleaseNotesKey = @"notes";
 NSString * const SQRLUpdateJSONNameKey = @"name";
 NSString * const SQRLUpdateJSONPublicationDateKey = @"pub_date";
 
+NSString * const SQRLUpdateErrorDomain = @"SQRLUpdateErrorDomain";
+
 @implementation SQRLUpdate
 
 #pragma mark Lifecycle
@@ -50,7 +52,7 @@ NSString * const SQRLUpdateJSONPublicationDateKey = @"pub_date";
 
 			*error = [NSError errorWithDomain:NSCocoaErrorDomain code:NSKeyValueValidationError userInfo:userInfo];
 		}
-		
+
 		return NO;
 	}
 
@@ -61,10 +63,10 @@ NSString * const SQRLUpdateJSONPublicationDateKey = @"pub_date";
 
 + (NSDictionary *)JSONKeyPathsByPropertyKey {
 	return @{
-		@keypath(SQRLUpdate.new, releaseNotes): @"notes",
-		@keypath(SQRLUpdate.new, releaseName): @"name",
-		@keypath(SQRLUpdate.new, releaseDate): @"pub_date",
-		@keypath(SQRLUpdate.new, updateURL): @"url",
+		@keypath(SQRLUpdate.new, releaseNotes): SQRLUpdateJSONReleaseNotesKey,
+		@keypath(SQRLUpdate.new, releaseName): SQRLUpdateJSONNameKey,
+		@keypath(SQRLUpdate.new, releaseDate): SQRLUpdateJSONPublicationDateKey,
+		@keypath(SQRLUpdate.new, updateURL): SQRLUpdateJSONURLKey,
 	};
 }
 
@@ -74,7 +76,7 @@ NSString * const SQRLUpdateJSONPublicationDateKey = @"pub_date";
 
 + (NSValueTransformer *)releaseDateJSONTransformer {
 	// ISO 8601 Time Zone with ':'
-	NSString * const ISO8601DateFormat = @"yyyy'-'MM'-'dd'T'HH':'mm':'ssZZZZZ";
+	NSString * const ISO8601DateFormat = @"yyyy'-'MM'-'DD'T'HH':'mm':'ssZZZZZ";
 
 	return [MTLValueTransformer reversibleTransformerWithForwardBlock:^ NSDate * (NSString *dateString) {
 		if (![dateString isKindOfClass:NSString.class]) return nil;
@@ -94,8 +96,8 @@ NSString * const SQRLUpdateJSONPublicationDateKey = @"pub_date";
 		}
 
 		// If neither match, try removing the ':' in the time zone
-		static NSRegularExpression *timeZoneSuffix = nil;
-		static dispatch_once_t timeZoneSuffixPredicate = 0;
+		static NSRegularExpression *timeZoneSuffix;
+		static dispatch_once_t timeZoneSuffixPredicate;
 		dispatch_once(&timeZoneSuffixPredicate, ^ {
 			timeZoneSuffix = [NSRegularExpression regularExpressionWithPattern:@"([-+])([0-9]{2}):([0-9]{2})$" options:0 error:NULL];
 		});
@@ -142,7 +144,7 @@ NSString * const SQRLUpdateJSONPublicationDateKey = @"pub_date";
 			};
 			*error = [NSError errorWithDomain:NSCocoaErrorDomain code:NSKeyValueValidationError userInfo:userInfo];
 		}
-		
+
 		return NO;
 	}
 

Squirrel/SQRLUpdater.h

@@ -6,26 +6,6 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Foundation/Foundation.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-
-// Represents the current state of the updater.
-//
-// SQRLUpdaterStateIdle              - Doing absolutely diddly squat.
-// SQRLUpdaterStateCheckingForUpdate - Checking for any updates from the server.
-// SQRLUpdaterStateDownloadingUpdate - Update found, downloading the archive.
-// SQRLUpdaterStateAwaitingRelaunch  - Awaiting a relaunch to install
-//                                     the update.
-typedef enum : NSUInteger {
-       SQRLUpdaterStateIdle,
-       SQRLUpdaterStateCheckingForUpdate,
-       SQRLUpdaterStateDownloadingUpdate,
-       SQRLUpdaterStateAwaitingRelaunch,
-} SQRLUpdaterState;
-
-// Block for providing download requests given a download url
-typedef NSURLRequest * (^SQRLRequestForDownload)(NSURL *);
-
 // The domain for errors originating within SQRLUpdater.
 extern NSString * const SQRLUpdaterErrorDomain;
 
@@ -63,7 +43,7 @@ extern NSString * const SQRLUpdaterServerDataErrorKey;
 // error with code `SQRLUpdaterErrorInvalidJSON` is generated.
 extern NSString * const SQRLUpdaterJSONObjectErrorKey;
 
-@class RACCommand;
+@class RACAction;
 @class RACDisposable;
 @class RACSignal;
 
@@ -72,19 +52,12 @@ extern NSString * const SQRLUpdaterJSONObjectErrorKey;
 
 // Kicks off a check for updates.
 //
-// If an update is available, it will be sent on `updates` once downloaded.
-@property (nonatomic, strong, readonly) RACCommand *checkForUpdatesCommand;
-
-// The current state of the manager.
-//
-// This property is KVO-compliant.
-@property (atomic, readonly) SQRLUpdaterState state;
+// If an update is available, it will be sent on
+// `[checkForUpdatesAction deferred]` and `updates` once downloaded.
+@property (nonatomic, strong, readonly) RACAction *checkForUpdatesAction;
 
 // Sends an `SQRLDownloadedUpdate` object on the main thread whenever a new
-// update is available.
-//
-// This signal is actually just `checkForUpdatesCommand.executionSignals`,
-// flattened for convenience.
+// update is available. Completes when the receiver deallocates.
 @property (nonatomic, strong, readonly) RACSignal *updates;
 
 // The request that will be sent to check for updates.
@@ -95,15 +68,6 @@ extern NSString * const SQRLUpdaterJSONObjectErrorKey;
 // This property must never be set to nil.
 @property (atomic, copy) NSURLRequest *updateRequest;
 
-// The block used for fetching a given download request
-//
-// The default value is the argument that was originally passed to
-// -initWithUpdateRequest:requestForDownload:.
-//
-// If initialized with -initWithUpdateRequest: this block will
-// return a generic NSURLRequest with the provided url.
-@property (nonatomic, copy) SQRLRequestForDownload requestForDownload;
-
 // The `SQRLUpdate` subclass to instantiate with the server's response.
 //
 // By default, this is `SQRLUpdate` itself, but it can be set to a custom
@@ -123,18 +87,6 @@ extern NSString * const SQRLUpdaterJSONObjectErrorKey;
 // Returns the initialized `SQRLUpdater`.
 - (id)initWithUpdateRequest:(NSURLRequest *)updateRequest;
 
-// Initializes an updater that will send the given request to check for updates
-// and passes a block to provide requests for the update downloads.
-//
-// updateRequest - Same as with initWithUpdateRequest
-// requestForDownload - Once the update url is found for the update download, allow
-//                      providing custom requests that can be costomized as desired.
-//                      Useful for including `Authorization` headers just like the
-//                      updateRequest param.
-//
-// Returns the initialized `SQRLUpdater`.
-- (id)initWithUpdateRequest:(NSURLRequest *)updateRequest requestForDownload:(SQRLRequestForDownload)requestForDownload;
-
 // Executes `checkForUpdatesCommand` (if enabled) every `interval` seconds.
 //
 // The first check will not occur until `interval` seconds have passed.

Squirrel/SQRLUpdater.m

@@ -15,12 +15,15 @@
 #import "SQRLDirectoryManager.h"
 #import "SQRLDownloadedUpdate.h"
 #import "SQRLShipItLauncher.h"
+#import "SQRLShipItState.h"
 #import "SQRLUpdate.h"
+#import "SQRLDownloadedUpdate.h"
 #import "SQRLZipArchiver.h"
-#import "SQRLShipItRequest.h"
 #import <ReactiveCocoa/EXTScope.h>
 #import <ReactiveCocoa/ReactiveCocoa.h>
-#import <sys/mount.h>
+#import "SQRLURLConnection.h"
+#import "SQRLURLConnection.h"
+#import "SQRLDownloadManager.h"
 
 NSString * const SQRLUpdaterErrorDomain = @"SQRLUpdaterErrorDomain";
 NSString * const SQRLUpdaterServerDataErrorKey = @"SQRLUpdaterServerDataErrorKey";
@@ -33,20 +36,10 @@ const NSInteger SQRLUpdaterErrorInvalidServerResponse = 5;
 const NSInteger SQRLUpdaterErrorInvalidJSON = 6;
 const NSInteger SQRLUpdaterErrorInvalidServerBody = 7;
 
-/// The application's being run on a read-only volume.
-const NSInteger SQRLUpdaterErrorReadOnlyVolume = 8;
-
-// The prefix used when creating temporary directories for updates. This will be
-// followed by a random string of characters.
-static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
-
 @interface SQRLUpdater ()
 
-@property (atomic, readwrite) SQRLUpdaterState state;
-
-/// The etag of the currently downloaded update, nil if no update has been
-/// downloaded.
-@property (atomic, copy) NSString *etag;
+// The directory manager used for downloads and unpacks.
+@property (nonatomic, strong, readonly) SQRLDirectoryManager *directoryManager;
 
 // The code signature for the running application, used to check updates before
 // sending them to ShipIt.
@@ -76,22 +69,25 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 // errors, on a background thread.
 - (RACSignal *)downloadAndPrepareUpdate:(SQRLUpdate *)update;
 
-// Downloads the archived bundle associated with the given update.
+// Downloads the update archive for the given update.
 //
 // update            - Describes the update to install. This must not be nil.
-// downloadDirectory - A directory in which to create a temporary directory for this
-//                     download. This must not be nil.
+// downloadDirectory - A directory in which to create a temporary directory for
+//                     this download. This must not be nil.
 //
-// Returns a signal which sends an unarchived `NSBundle` then completes, or
-// errors, on a background thread.
-- (RACSignal *)downloadBundleForUpdate:(SQRLUpdate *)update intoDirectory:(NSURL *)downloadDirectory;
+// Returns a signal which sends an NSURL of the downloaded update archive then
+// completes, or errors, on a background thread.
+- (RACSignal *)downloadArchiveForUpdate:(SQRLUpdate *)update intoDirectory:(NSURL *)downloadDirectory;
 
-// Creates a unique directory in which to save the update bundle, for later use
-// by ShipIt.
+// Unpacks an update archive.
 //
-// Returns a signal which sends an `NSURL` then completes, or errors, on an
-// unspecified thread.
-- (RACSignal *)uniqueTemporaryDirectoryForUpdate;
+// archiveURL   - The location of the update archive, currently only ZIP
+//                archives are supported. Must not be nil.
+// directoryURL - A directory in which to place the unpacked contents of the
+//                archive. Must not be nil.
+//
+// Returns a signal which completes or errors.
+- (RACSignal *)unpackArchiveAtURL:(NSURL *)archiveURL intoDirectory:(NSURL *)directoryURL;
 
 // Recursively searches the given directory for an application bundle that has
 // the same identifier as the running application.
@@ -124,16 +120,27 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 // Returns a signal which completes or errors on a background thread.
 - (RACSignal *)prepareUpdateForInstallation:(SQRLDownloadedUpdate *)update;
 
+// Verifies that an existing state is innocuous, and therefore safe to
+// overwrite.
+//
+// This won't be the case if, for example, an update is currently being
+// installed.
+//
+// Returns a signal which sends `existingState` then completes upon successful
+// validation, or errors otherwise.
+- (RACSignal *)validateExistingState:(SQRLShipItState *)existingState;
+
 @end
 
-@implementation SQRLUpdater
+@implementation SQRLUpdater {
+	RACSubject *_updates;
+}
 
 #pragma mark Properties
 
 - (RACSignal *)updates {
-	return [[self.checkForUpdatesCommand.executionSignals
-		concat]
-		setNameWithFormat:@"%@ -updates", self];
+	return [_updates
+		deliverOn:RACScheduler.mainThreadScheduler];
 }
 
 #pragma mark Lifecycle
@@ -144,127 +151,57 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 }
 
 - (id)initWithUpdateRequest:(NSURLRequest *)updateRequest {
-	return [self initWithUpdateRequest:updateRequest requestForDownload:^(NSURL *downloadURL) {
-		return [NSURLRequest requestWithURL:downloadURL];
-	}];
-}
-
-- (id)initWithUpdateRequest:(NSURLRequest *)updateRequest requestForDownload:(SQRLRequestForDownload)requestForDownload {
 	NSParameterAssert(updateRequest != nil);
-	NSParameterAssert(requestForDownload != nil);
 
 	self = [super init];
 	if (self == nil) return nil;
 
-	_requestForDownload = [requestForDownload copy];
 	_updateRequest = [updateRequest copy];
 	_updateClass = SQRLUpdate.class;
 
+	_directoryManager = SQRLDirectoryManager.currentApplicationManager;
+
 	NSError *error = nil;
 	_signature = [SQRLCodeSignature currentApplicationSignature:&error];
-	if (_signature == nil) {
-#if DEBUG
-		NSLog(@"Could not get code signature for running application, application updates are disabled: %@", error);
-		return nil;
-#else
-		NSDictionary *exceptionInfo = @{ NSUnderlyingErrorKey: error };
-		@throw [NSException exceptionWithName:NSInternalInconsistencyException reason:@"Could not get code signature for running application" userInfo:exceptionInfo];
-#endif
-	}
+	NSAssert(_signature != nil, @"Could not get code signature for running application: %@", error);
 
-	BOOL updatesDisabled = (getenv("DISABLE_UPDATE_CHECK") != NULL);
 	@weakify(self);
-
-	_checkForUpdatesCommand = [[RACCommand alloc] initWithEnabled:[RACSignal return:@(!updatesDisabled)] signalBlock:^(id _) {
-		@strongify(self);
-		NSParameterAssert(self.updateRequest != nil);
-
-		// TODO: Maybe allow this to be an argument to the command?
-		NSMutableURLRequest *request = [self.updateRequest mutableCopy];
-		[request setValue:@"application/json" forHTTPHeaderField:@"Accept"];
-
-		return [[[[[[[[self
-			performHousekeeping]
-			then:^{
-				self.state = SQRLUpdaterStateCheckingForUpdate;
-
-				return [NSURLConnection rac_sendAsynchronousRequest:request];
-			}]
-			reduceEach:^(NSURLResponse *response, NSData *bodyData) {
-				if ([response isKindOfClass:NSHTTPURLResponse.class]) {
-					NSHTTPURLResponse *httpResponse = (id)response;
-					if (!(httpResponse.statusCode >= 200 && httpResponse.statusCode <= 299)) {
-						NSDictionary *errorInfo = @{
-							NSLocalizedDescriptionKey: NSLocalizedString(@"Update check failed", nil),
-							NSLocalizedRecoverySuggestionErrorKey: NSLocalizedString(@"The server sent an invalid response. Try again later.", nil),
-							SQRLUpdaterServerDataErrorKey: bodyData,
-						};
-						NSError *error = [NSError errorWithDomain:SQRLUpdaterErrorDomain code:SQRLUpdaterErrorInvalidServerResponse userInfo:errorInfo];
-						return [RACSignal error:error];
-					}
-
-					if (httpResponse.statusCode == 204 /* No Content */) {
-						return [RACSignal empty];
-					}
-
-					BOOL readOnlyVolume = [self isRunningOnReadOnlyVolume];
-					if (readOnlyVolume) {
-						NSDictionary *errorInfo = @{
-						NSLocalizedDescriptionKey: NSLocalizedString(@"Cannot update while running on a read-only volume", nil),
-						NSLocalizedRecoverySuggestionErrorKey: NSLocalizedString(@"The application is on a read-only volume. Please move the application and try again. If you're on macOS Sierra or later, you'll need to move the application out of the Downloads directory. See https://github.com/Squirrel/Squirrel.Mac/issues/182 for more information.", nil),
-						};
-						NSError *error = [NSError errorWithDomain:SQRLUpdaterErrorDomain code:SQRLUpdaterErrorReadOnlyVolume userInfo:errorInfo];
-						return [RACSignal error:error];
-					}
-				}
-
-				return [RACSignal return:bodyData];
-			}]
-			flatten]
-			flattenMap:^(NSData *data) {
-				return [self updateFromJSONData:data];
-			}]
-			flattenMap:^(SQRLUpdate *update) {
-				return [[RACSignal
-					defer:^{
-						self.state = SQRLUpdaterStateDownloadingUpdate;
-
-						return [self downloadAndPrepareUpdate:update];
-					}]
-					doCompleted:^{
-						self.state = SQRLUpdaterStateAwaitingRelaunch;
-					}];
-			}]
-			finally:^{
-				if (self.state == SQRLUpdaterStateAwaitingRelaunch) return;
-				self.state = SQRLUpdaterStateIdle;
-			}]
-			deliverOn:RACScheduler.mainThreadScheduler];
-	}];
-
-	_shipItLauncher = [[[RACSignal
+	_checkForUpdatesAction = [[[RACSignal
 		defer:^{
 			@strongify(self);
+			return [RACSignal return:self.updateRequest];
+		}]
+		flattenMap:^(NSURLRequest *request) {
+			@strongify(self);
+			return [self checkForUpdates:request];
+		}]
+		action];
 
+	_updates = [[RACSubject
+		subject]
+		setNameWithFormat:@"%@ updates", self];
+
+	_shipItLauncher = [[[[RACSignal
+		defer:^{
 			NSURL *targetURL = NSRunningApplication.currentApplication.bundleURL;
 
-			BOOL targetWritable = [self canWriteToURL:targetURL];
-			BOOL parentWritable = [self canWriteToURL:targetURL.URLByDeletingLastPathComponent];
-			return [SQRLShipItLauncher launchPrivileged:!targetWritable || !parentWritable];
+			NSNumber *targetWritable = nil;
+			NSError *targetWritableError = nil;
+			BOOL gotWritable = [targetURL getResourceValue:&targetWritable forKey:NSURLIsWritableKey error:&targetWritableError];
+
+			// If we can't determine whether it can be written, assume nonprivileged and
+			// wait for another, more canonical error.
+			return [SQRLShipItLauncher launchPrivileged:(gotWritable && !targetWritable.boolValue)];
 		}]
-		replayLazily]
+		promiseOnScheduler:RACScheduler.immediateScheduler]
+		deferred]
 		setNameWithFormat:@"shipItLauncher"];
-	
+
 	return self;
 }
 
-- (BOOL)canWriteToURL:(NSURL *)fileURL {
-	NSNumber *writable = nil;
-	NSError *writableError = nil;
-	BOOL gotWritable = [fileURL getResourceValue:&writable forKey:NSURLIsWritableKey error:&writableError];
-	// If we can't determine whether it can be written, assume nonprivileged and
-	// wait for another, more canonical error.
-	return !gotWritable || writable.boolValue;
+- (void)dealloc {
+	[_updates sendCompleted];
 }
 
 #pragma mark Checking for Updates
@@ -272,20 +209,64 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 - (RACDisposable *)startAutomaticChecksWithInterval:(NSTimeInterval)interval {
 	@weakify(self);
 
-	return [[[[[RACSignal
+	return [[[[RACSignal
 		interval:interval onScheduler:[RACScheduler schedulerWithPriority:RACSchedulerPriorityBackground]]
 		flattenMap:^(id _) {
 			@strongify(self);
-			return [[self.checkForUpdatesCommand
-				execute:RACUnit.defaultUnit]
+
+			return [[[self.checkForUpdatesAction
+				deferred]
+				ignoreValues]
 				catch:^(NSError *error) {
 					NSLog(@"Error checking for updates: %@", error);
 					return [RACSignal empty];
 				}];
 		}]
 		takeUntil:self.rac_willDeallocSignal]
-		publish]
-		connect];
+		subscribeCompleted:^{}];
+}
+
+- (RACSignal *)checkForUpdates:(NSURLRequest *)request {
+	NSParameterAssert(request != nil);
+
+	BOOL updatesDisabled = (getenv("DISABLE_UPDATE_CHECK") != NULL);
+	if (updatesDisabled) return [RACSignal empty];
+
+	NSMutableURLRequest *newRequest = [request mutableCopy];
+	[newRequest setValue:@"application/json" forHTTPHeaderField:@"Accept"];
+
+	return [[[[[[NSURLConnection
+		rac_sendAsynchronousRequest:newRequest]
+		reduceEach:^(NSURLResponse *response, NSData *bodyData) {
+		if ([response isKindOfClass:NSHTTPURLResponse.class]) {
+			NSHTTPURLResponse *httpResponse = (id)response;
+			if (!(httpResponse.statusCode >= 200 && httpResponse.statusCode <= 299)) {
+				NSDictionary *errorInfo = @{
+					NSLocalizedDescriptionKey: NSLocalizedString(@"Update check failed", nil),
+					NSLocalizedRecoverySuggestionErrorKey: NSLocalizedString(@"The server sent an invalid response. Try again later.", nil),
+					SQRLUpdaterServerDataErrorKey: bodyData,
+				};
+				NSError *error = [NSError errorWithDomain:SQRLUpdaterErrorDomain code:SQRLUpdaterErrorInvalidServerResponse userInfo:errorInfo];
+				return [RACSignal error:error];
+			}
+
+			if (httpResponse.statusCode == 204 /* No Content */) {
+				return [RACSignal empty];
+			}
+		}
+
+		return [RACSignal return:bodyData];
+	}]
+	flatten]
+	flattenMap:^(NSData *data) {
+		return [self updateFromJSONData:data];
+	}]
+	flattenMap:^(SQRLUpdate *update) {
+		return [self downloadAndPrepareUpdate:update];
+	}]
+	doNext:^(SQRLDownloadedUpdate *update) {
+		[self->_updates sendNext:update];
+	}];
 }
 
 - (RACSignal *)updateFromJSONData:(NSData *)data {
@@ -327,144 +308,93 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 		setNameWithFormat:@"%@ -updateFromJSONData:", self];
 }
 
+#pragma Download
+
 - (RACSignal *)downloadAndPrepareUpdate:(SQRLUpdate *)update {
 	NSParameterAssert(update != nil);
 
-	return [[[self
-		uniqueTemporaryDirectoryForUpdate]
+	return [[[self.directoryManager
+		createUniqueUpdateDirectoryURL]
 		flattenMap:^(NSURL *downloadDirectory) {
-			void (^cleanUp)(void) = ^{
-				NSError *error;
-				if (![NSFileManager.defaultManager removeItemAtURL:downloadDirectory error:&error]) {
-					NSLog(@"Error removing temporary download directory at %@: %@", downloadDirectory, error.sqrl_verboseDescription);
-				}
-			};
-
-			return [[[self
-				downloadBundleForUpdate:update intoDirectory:downloadDirectory]
+			return [[[[[[self
+				downloadArchiveForUpdate:update intoDirectory:downloadDirectory]
+				flattenMap:^(NSURL *updateArchiveURL) {
+					return [self unpackArchiveAtURL:updateArchiveURL intoDirectory:downloadDirectory];
+				}]
+				ignoreValues]
+				concat:[self updateBundleMatchingCurrentApplicationInDirectory:downloadDirectory]]
 				flattenMap:^(NSBundle *updateBundle) {
-					// If the bundle is nil it means our conditional GET told us
-					// we already downloaded the update. So just clean up.
-					if (updateBundle == nil) {
-						cleanUp();
-						return [RACSignal empty];
-					}
-
 					return [self verifyAndPrepareUpdate:update fromBundle:updateBundle];
 				}]
 				doError:^(id _) {
-					cleanUp();
+					NSError *error = nil;
+					if (![NSFileManager.defaultManager removeItemAtURL:downloadDirectory error:&error]) {
+						NSLog(@"Error removing temporary download directory at %@: %@", downloadDirectory, error.sqrl_verboseDescription);
+					}
 				}];
 		}]
 		setNameWithFormat:@"%@ -downloadAndPrepareUpdate: %@", self, update];
 }
 
-- (RACSignal *)unarchiveAndPrepareData:(NSData *)data withName:(NSString *)name intoDirectory:(NSURL *)downloadDirectory {
-	return [[[[[RACSignal
-		defer:^{
-			NSURL *zipOutputURL = [downloadDirectory URLByAppendingPathComponent:name];
-			NSError *error = nil;
-			if ([data writeToURL:zipOutputURL options:NSDataWritingAtomic error:&error]) {
-				return [RACSignal return:zipOutputURL];
-			} else {
-				return [RACSignal error:error];
-			}
-		}]
-		doNext:^(NSURL *zipOutputURL) {
-			NSLog(@"Download completed to: %@", zipOutputURL);
-		}]
-		flattenMap:^(NSURL *zipOutputURL) {
-			return [[[[SQRLZipArchiver
-				unzipArchiveAtURL:zipOutputURL intoDirectoryAtURL:downloadDirectory]
-				ignoreValues]
-				concat:[RACSignal return:zipOutputURL]]
-				doCompleted:^{
-					NSError *error = nil;
-					if (![NSFileManager.defaultManager removeItemAtURL:zipOutputURL error:&error]) {
-						NSLog(@"Error removing downloaded archive at %@: %@", zipOutputURL, error.sqrl_verboseDescription);
-					}
-				}];
-		}]
-		flattenMap:^(NSURL *zipOutputURL) {
-			return [self updateBundleMatchingCurrentApplicationInDirectory:downloadDirectory];
-		}]
-		setNameWithFormat:@"%@ -unarchiveAndPrepareData:withName: %@ intoDirectory: %@", self, name, downloadDirectory];
-}
-
-- (RACSignal *)downloadBundleForUpdate:(SQRLUpdate *)update intoDirectory:(NSURL *)downloadDirectory {
+- (RACSignal *)downloadArchiveForUpdate:(SQRLUpdate *)update intoDirectory:(NSURL *)downloadDirectory {
 	NSParameterAssert(update != nil);
 	NSParameterAssert(downloadDirectory != nil);
 
-	return [[RACSignal
+	return [[[RACSignal
 		defer:^{
 			NSURL *zipDownloadURL = update.updateURL;
-			NSMutableURLRequest *zipDownloadRequest = [self.requestForDownload(zipDownloadURL) mutableCopy];
-
+			NSMutableURLRequest *zipDownloadRequest = [NSMutableURLRequest requestWithURL:zipDownloadURL];
 			[zipDownloadRequest setValue:@"application/zip" forHTTPHeaderField:@"Accept"];
-			if (self.etag != nil) {
-				[zipDownloadRequest setValue:self.etag forHTTPHeaderField:@"If-None-Match"];
-			}
 
-			return [[[NSURLConnection
-				rac_sendAsynchronousRequest:zipDownloadRequest]
-				reduceEach:^(NSURLResponse *response, NSData *bodyData) {
+			SQRLURLConnection *connection = [[SQRLURLConnection alloc] initWithRequest:zipDownloadRequest];
+
+			SQRLDownloadManager *downloadManager = [[SQRLDownloadManager alloc] initWithDirectoryManager:self.directoryManager];
+
+			return [[[[connection
+				download:downloadManager]
+				reduceEach:^(NSURLResponse *response, NSURL *bodyLocation) {
 					if ([response isKindOfClass:NSHTTPURLResponse.class]) {
 						NSHTTPURLResponse *httpResponse = (id)response;
-
-						if (httpResponse.statusCode == 304 /* Not Modified */) {
-							return [RACSignal return:nil];
-						}
-
 						if (!(httpResponse.statusCode >= 200 && httpResponse.statusCode <= 299)) {
 							NSDictionary *errorInfo = @{
 								NSLocalizedDescriptionKey: NSLocalizedString(@"Update download failed", nil),
 								NSLocalizedRecoverySuggestionErrorKey: NSLocalizedString(@"The server sent an invalid response. Try again later.", nil),
-								SQRLUpdaterServerDataErrorKey: bodyData,
 							};
 							NSError *error = [NSError errorWithDomain:SQRLUpdaterErrorDomain code:SQRLUpdaterErrorInvalidServerResponse userInfo:errorInfo];
 							return [RACSignal error:error];
 						}
-
-						self.etag = httpResponse.allHeaderFields[@"ETag"];
 					}
 
-					return [self unarchiveAndPrepareData:bodyData withName:zipDownloadURL.lastPathComponent intoDirectory:downloadDirectory];
+					return [[RACSignal
+						return:bodyLocation]
+						tryMap:^ NSURL * (NSURL *bodyLocation, NSError **errorRef) {
+							NSURL *updateLocation = [downloadDirectory URLByAppendingPathComponent:response.suggestedFilename];
+							if (![NSFileManager.defaultManager moveItemAtURL:bodyLocation toURL:updateLocation error:errorRef]) return nil;
+							return updateLocation;
+						}];
 				}]
-				flatten];
+				flatten]
+				concat:[[downloadManager
+					removeAllResumableDownloads]
+					catchTo:RACSignal.empty]];
 		}]
-		setNameWithFormat:@"%@ -downloadBundleForUpdate: %@ intoDirectory: %@", self, update, downloadDirectory];
+		doNext:^(NSURL *zipOutputURL) {
+			NSLog(@"Download completed to: %@", zipOutputURL);
+		}]
+		setNameWithFormat:@"%@ -downloadArchiveForUpdate: %@ intoDirectory: %@", self, update, downloadDirectory];
 }
 
 #pragma mark File Management
 
-- (RACSignal *)uniqueTemporaryDirectoryForUpdate {
-	return [[[RACSignal
+- (RACSignal *)unpackArchiveAtURL:(NSURL *)archiveURL intoDirectory:(NSURL *)directoryURL {
+	NSParameterAssert(archiveURL != nil);
+	NSParameterAssert(directoryURL != nil);
+
+	return [[RACSignal
 		defer:^{
-			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:SQRLShipItLauncher.shipItJobLabel];
-			return [directoryManager storageURL];
+			return [SQRLZipArchiver unzipArchiveAtURL:archiveURL intoDirectoryAtURL:directoryURL];
 		}]
-		flattenMap:^(NSURL *storageURL) {
-			NSURL *updateDirectoryTemplate = [storageURL URLByAppendingPathComponent:[SQRLUpdaterUniqueTemporaryDirectoryPrefix stringByAppendingString:@"XXXXXXX"]];
-			char *updateDirectoryCString = strdup(updateDirectoryTemplate.path.fileSystemRepresentation);
-			@onExit {
-				free(updateDirectoryCString);
-			};
-			
-			if (mkdtemp(updateDirectoryCString) == NULL) {
-				int code = errno;
-
-				NSDictionary *userInfo = @{
-					NSLocalizedDescriptionKey: NSLocalizedString(@"Could not create temporary directory", nil),
-					NSURLErrorKey: updateDirectoryTemplate
-				};
-
-				return [RACSignal error:[NSError errorWithDomain:NSPOSIXErrorDomain code:code userInfo:userInfo]];
-			}
-
-			NSString *updateDirectoryPath = [NSFileManager.defaultManager stringWithFileSystemRepresentation:updateDirectoryCString length:strlen(updateDirectoryCString)];
-			return [RACSignal return:[NSURL fileURLWithPath:updateDirectoryPath isDirectory:YES]];
-		}]
-		setNameWithFormat:@"%@ -uniqueTemporaryDirectoryForUpdate", self];
+		setNameWithFormat:@"%@ unpackArchiveAtURL: %@ intoDirectory: %@", self, archiveURL, directoryURL];
 }
 
 - (RACSignal *)updateBundleMatchingCurrentApplicationInDirectory:(NSURL *)directory {
@@ -477,25 +407,28 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 				NSLog(@"Error enumerating item %@ within directory %@: %@", URL, directory, error);
 				return YES;
 			}];
-			
-			NSURL *updateBundleURL = [enumerator.rac_sequence objectPassingTest:^(NSURL *URL) {
-				NSString *type = nil;
-				NSError *error = nil;
-				if (![URL getResourceValue:&type forKey:NSURLTypeIdentifierKey error:&error]) {
-					NSLog(@"Error retrieving UTI for item at %@: %@", URL, error);
-					return NO;
-				}
 
-				if (!UTTypeConformsTo((__bridge CFStringRef)type, kUTTypeApplicationBundle)) return NO;
+			NSURL *updateBundleURL = [[[enumerator.rac_promise
+				start]
+				filter:^(NSURL *URL) {
+					NSString *type = nil;
+					NSError *error = nil;
+					if (![URL getResourceValue:&type forKey:NSURLTypeIdentifierKey error:&error]) {
+						NSLog(@"Error retrieving UTI for item at %@: %@", URL, error);
+						return NO;
+					}
 
-				NSBundle *bundle = [NSBundle bundleWithURL:URL];
-				if (bundle == nil) {
-					NSLog(@"Could not open application bundle at %@", URL);
-					return NO;
-				}
+					if (!UTTypeConformsTo((__bridge CFStringRef)type, kUTTypeApplicationBundle)) return NO;
 
-				return [bundle.bundleIdentifier isEqual:NSRunningApplication.currentApplication.bundleIdentifier];
-			}];
+					NSBundle *bundle = [NSBundle bundleWithURL:URL];
+					if (bundle == nil) {
+						NSLog(@"Could not open application bundle at %@", URL);
+						return NO;
+					}
+
+					return [bundle.bundleIdentifier isEqual:NSRunningApplication.currentApplication.bundleIdentifier];
+				}]
+				first];
 
 			if (updateBundleURL != nil) {
 				return [RACSignal return:updateBundleURL];
@@ -522,100 +455,6 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 		setNameWithFormat:@"%@ -shipItStateURL", self];
 }
 
-/// Is the host app running on a read-only volume?
-- (BOOL)isRunningOnReadOnlyVolume {
-	struct statfs statfsInfo;
-	NSURL *bundleURL = NSRunningApplication.currentApplication.bundleURL;
-	int result = statfs(bundleURL.fileSystemRepresentation, &statfsInfo);
-	if (result == 0) {
-		return (statfsInfo.f_flags & MNT_RDONLY) != 0;
-	} else {
-		// If we can't even check if the volume is read-only, assume it is.
-		return true;
-	}
-}
-
-- (RACSignal *)performHousekeeping {
-	return [[RACSignal
-		merge:@[ [self pruneUpdateDirectories], [self truncateLogs] ]]
-		catch:^(NSError *error) {
-			NSLog(@"Error doing housekeeping: %@", error);
-			return [RACSignal empty];
-		}];
-}
-
-/// Lazily removes outdated temporary directories (used for previous updates)
-/// upon subscription.
-///
-/// Pruning directories while an update is pending or in progress will result in
-/// undefined behavior.
-///
-/// Sends each removed directory then completes, or errors, on an unspecified
-/// thread.
-- (RACSignal *)pruneUpdateDirectories {
-	return [[[RACSignal
-		defer:^{
-			// If we already have updates downloaded we don't wanna prune them.
-			if (self.state == SQRLUpdaterStateAwaitingRelaunch) return [RACSignal empty];
-
-			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:SQRLShipItLauncher.shipItJobLabel];
-			return [directoryManager storageURL];
-		}]
-		flattenMap:^(NSURL *storageURL) {
-			NSFileManager *manager = [[NSFileManager alloc] init];
-			NSDirectoryEnumerator *enumerator = [manager enumeratorAtURL:storageURL includingPropertiesForKeys:nil options:NSDirectoryEnumerationSkipsSubdirectoryDescendants errorHandler:^(NSURL *URL, NSError *error) {
-				NSLog(@"Error enumerating item %@ within directory %@: %@", URL, storageURL, error);
-				return YES;
-			}];
-
-			return [[enumerator.rac_sequence.signal
-				filter:^(NSURL *enumeratedURL) {
-					NSString *name = enumeratedURL.lastPathComponent;
-					return [name hasPrefix:SQRLUpdaterUniqueTemporaryDirectoryPrefix];
-				}]
-				doNext:^(NSURL *directoryURL) {
-					NSError *error = nil;
-					if (![manager removeItemAtURL:directoryURL error:&error]) {
-						NSLog(@"Error removing old update directory at %@: %@", directoryURL, error.sqrl_verboseDescription);
-					}
-				}];
-		}]
-		setNameWithFormat:@"%@ -prunedUpdateDirectories", self];
-}
-
-
-// Like truncation, but backwards.
-- (RACSignal *)backwardTruncateFile:(NSURL *)fileURL {
-	return [RACSignal defer:^{
-		static const NSInteger MAX_LENGTH = 1024 * 1024 * 8;
-
-		NSError *error;
-		NSFileHandle *handle = [NSFileHandle fileHandleForWritingToURL:fileURL error:&error];
-		if (handle == nil) return [RACSignal error:error];
-
-		unsigned long long fileLength = [handle seekToEndOfFile];
-		if (fileLength <= MAX_LENGTH) return [RACSignal empty];
-
-		[handle seekToFileOffset:fileLength - MAX_LENGTH];
-		NSData *mostRecentData = [handle readDataToEndOfFile];
-		[handle truncateFileAtOffset:0];
-		[handle writeData:mostRecentData];
-
-		return [RACSignal empty];
-	}];
-}
-
-- (RACSignal *)truncateLogs {
-	return [[RACSignal
-		defer:^{
-			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:SQRLShipItLauncher.shipItJobLabel];
-			return [RACSignal zip:@[ [directoryManager shipItStdoutURL], [directoryManager shipItStderrURL] ]];
-		}]
-		reduceEach:^(NSURL *stdoutURL, NSURL *stderrURL) {
-			return [RACSignal merge:@[ [self backwardTruncateFile:stdoutURL], [self backwardTruncateFile:stderrURL] ]];
-		}];
-}
-
 #pragma mark Installing Updates
 
 - (RACSignal *)verifyAndPrepareUpdate:(SQRLUpdate *)update fromBundle:(NSBundle *)updateBundle {
@@ -624,47 +463,62 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 
 	return [[[[self.signature
 		verifyBundleAtURL:updateBundle.bundleURL]
-		then:^{
-			SQRLDownloadedUpdate *downloadedUpdate = [[SQRLDownloadedUpdate alloc] initWithUpdate:update bundle:updateBundle];
-			return [RACSignal return:downloadedUpdate];
-		}]
+		concat:[RACSignal return:[[SQRLDownloadedUpdate alloc] initWithUpdate:update bundle:updateBundle]]]
 		flattenMap:^(SQRLDownloadedUpdate *downloadedUpdate) {
-			return [[self prepareUpdateForInstallation:downloadedUpdate] then:^{
-				return [RACSignal return:downloadedUpdate];
-			}];
+			return [[self
+				prepareUpdateForInstallation:downloadedUpdate]
+				concat:[RACSignal return:downloadedUpdate]];
 		}]
 		setNameWithFormat:@"%@ -verifyAndPrepareUpdate: %@ fromBundle: %@", self, update, updateBundle];
 }
 
+- (RACSignal *)validateExistingState:(SQRLShipItState *)existingState {
+	return [[RACSignal
+		defer:^{
+			if (existingState.installerState != SQRLInstallerStateNothingToDo) {
+				// If this happens, shit is crazy, because it implies that an
+				// update is being installed over us right now.
+				NSDictionary *userInfo = @{
+					NSLocalizedDescriptionKey: NSLocalizedString(@"Installation in progress", nil),
+					NSLocalizedRecoverySuggestionErrorKey: [NSString stringWithFormat:NSLocalizedString(@"An update for %@ is already in progress.", nil), NSRunningApplication.currentApplication.bundleIdentifier],
+				};
+
+				return [RACSignal error:[NSError errorWithDomain:SQRLUpdaterErrorDomain code:SQRLUpdaterErrorPreparingUpdateJob userInfo:userInfo]];
+			}
+
+			return [RACSignal return:existingState];
+		}]
+		setNameWithFormat:@"%@ -validateExistingState: %@", self, existingState];
+}
+
 - (RACSignal *)prepareUpdateForInstallation:(SQRLDownloadedUpdate *)update {
 	NSParameterAssert(update != nil);
 
-	return [[[[RACSignal
-		defer:^{
-			NSRunningApplication *currentApplication = NSRunningApplication.currentApplication;
-			NSBundle *appBundle = [NSBundle bundleWithURL:currentApplication.bundleURL];
-			// Only use the update bundle's name if the user hasn't renamed the
-			// app themselves.
-			BOOL useUpdateBundleName = [appBundle.sqrl_executableName isEqual:currentApplication.bundleURL.lastPathComponent.stringByDeletingPathExtension];
-
-			SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:update.bundle.bundleURL targetBundleURL:currentApplication.bundleURL bundleIdentifier:currentApplication.bundleIdentifier launchAfterInstallation:NO useUpdateBundleName:useUpdateBundleName];
-			return [request writeUsingURL:self.shipItStateURL];
-		}]
-		then:^{
-			return self.shipItLauncher;
+	return [[[[[[[[SQRLShipItState
+		readUsingURL:self.shipItStateURL]
+		catchTo:[RACSignal empty]]
+		flattenMap:^(SQRLShipItState *existingState) {
+			return [self validateExistingState:existingState];
 		}]
+		ignoreValues]
+		concat:[RACSignal defer:^{
+			SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:NSRunningApplication.currentApplication.bundleURL updateBundleURL:update.bundle.bundleURL bundleIdentifier:NSRunningApplication.currentApplication.bundleIdentifier codeSignature:self.signature];
+			return [state writeUsingURL:self.shipItStateURL];
+		}]]
+		concat:self.shipItLauncher]
 		sqrl_addTransactionWithName:NSLocalizedString(@"Preparing update", nil) description:NSLocalizedString(@"An update for %@ is being prepared. Interrupting the process could corrupt the application.", nil), NSRunningApplication.currentApplication.bundleIdentifier]
 		setNameWithFormat:@"%@ -prepareUpdateForInstallation: %@", self, update];
 }
 
 - (RACSignal *)relaunchToInstallUpdate {
-	return [[[[[[[[SQRLShipItRequest
+	return [[[[[[[[[SQRLShipItState
 		readUsingURL:self.shipItStateURL]
-		map:^(SQRLShipItRequest *request) {
-			return [[SQRLShipItRequest alloc] initWithUpdateBundleURL:request.updateBundleURL targetBundleURL:request.targetBundleURL bundleIdentifier:request.bundleIdentifier launchAfterInstallation:YES useUpdateBundleName:request.useUpdateBundleName];
+		flattenMap:^(SQRLShipItState *existingState) {
+			return [self validateExistingState:existingState];
 		}]
-		flattenMap:^(SQRLShipItRequest *request) {
-			return [[request
+		flattenMap:^(SQRLShipItState *state) {
+			state.relaunchAfterInstallation = YES;
+			return [[state
 				writeUsingURL:self.shipItStateURL]
 				sqrl_addTransactionWithName:NSLocalizedString(@"Preparing to relaunch", nil) description:NSLocalizedString(@"%@ is preparing to relaunch to install an update. Interrupting the process could corrupt the application.", nil), NSRunningApplication.currentApplication.bundleIdentifier];
 		}]
@@ -675,7 +529,8 @@ static NSString * const SQRLUpdaterUniqueTemporaryDirectoryPrefix = @"update.";
 		// Never allow `completed` to escape this signal chain (in case
 		// -terminate: is asynchronous or something crazy).
 		concat:[RACSignal never]]
-		replay]
+		promiseOnScheduler:RACScheduler.immediateScheduler]
+		deferred]
 		setNameWithFormat:@"%@ -relaunchToInstallUpdate", self];
 }
 

Squirrel/SQRLZipArchiver.m

@@ -130,25 +130,23 @@ const NSInteger SQRLZipArchiverShellTaskFailed = 1;
 		// This is important because the signals on `self` complete upon
 		// dealloc.
 		return:self]
-		then:^{
-			return [RACSignal
-				zip:@[ self.taskTerminated, self.standardErrorData ]
-				reduce:^(NSNumber *exitStatus, NSData *errorData) {
-					if (exitStatus.intValue == 0) return [RACSignal empty];
+		ignoreValues]
+		concat:[RACSignal
+			zip:@[ self.taskTerminated, self.standardErrorData ]
+			reduce:^(NSNumber *exitStatus, NSData *errorData) {
+				if (exitStatus.intValue == 0) return [RACSignal empty];
 
-					NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
-					userInfo[SQRLZipArchiverExitCodeErrorKey] = exitStatus;
+				NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
+				userInfo[SQRLZipArchiverExitCodeErrorKey] = exitStatus;
 
-					NSString *errorString = [[NSString alloc] initWithData:errorData encoding:NSUTF8StringEncoding];
-					errorString = [errorString stringByTrimmingCharactersInSet:NSCharacterSet.whitespaceAndNewlineCharacterSet];
-					if (errorString.length > 0) userInfo[NSLocalizedDescriptionKey] = errorString;
+				NSString *errorString = [[NSString alloc] initWithData:errorData encoding:NSUTF8StringEncoding];
+				errorString = [errorString stringByTrimmingCharactersInSet:NSCharacterSet.whitespaceAndNewlineCharacterSet];
+				if (errorString.length > 0) userInfo[NSLocalizedDescriptionKey] = errorString;
 
-					return [RACSignal error:[NSError errorWithDomain:SQRLZipArchiverErrorDomain code:SQRLZipArchiverShellTaskFailed userInfo:userInfo]];
-				}];
-		}]
+				return [RACSignal error:[NSError errorWithDomain:SQRLZipArchiverErrorDomain code:SQRLZipArchiverShellTaskFailed userInfo:userInfo]];
+			}]]
 		take:1]
 		flatten]
-		replay]
 		setNameWithFormat:@"-launchWithArguments: %@", arguments];
 
 	self.dittoTask.arguments = arguments;

Squirrel/ShipIt-main.m

@@ -7,18 +7,15 @@
 //
 
 #import <Foundation/Foundation.h>
-
-#import "EXTScope.h"
-#import <ReactiveCocoa/RACCommand.h>
-#import <ReactiveCocoa/RACSignal+Operations.h>
-#import <ReactiveCocoa/RACScheduler.h>
-
+#import <ReactiveCocoa/EXTScope.h>
+#import <ReactiveCocoa/ReactiveCocoa.h>
 #import "NSError+SQRLVerbosityExtensions.h"
 #import "RACSignal+SQRLTransactionExtensions.h"
+#import "SQRLCodeSignature.h"
+#import "SQRLDirectoryManager.h"
 #import "SQRLInstaller.h"
-#import "SQRLInstaller+Private.h"
+#import "SQRLShipItState.h"
 #import "SQRLTerminationListener.h"
-#import "SQRLShipItRequest.h"
 
 // The maximum number of times ShipIt should run the same installation state, in
 // an attempt to update.
@@ -30,133 +27,124 @@ static const NSUInteger SQRLShipItMaximumInstallationAttempts = 3;
 // The domain for errors generated here.
 static NSString * const SQRLShipItErrorDomain = @"SQRLShipItErrorDomain";
 
-static NSUInteger installationAttempts(NSString *applicationIdentifier) {
-	return CFPreferencesGetAppIntegerValue((__bridge CFStringRef)SQRLShipItInstallationAttemptsKey, (__bridge CFStringRef)applicationIdentifier, NULL);
-}
-
-static BOOL setInstallationAttempts(NSString *applicationIdentifier, NSUInteger attempts) {
-	CFPreferencesSetValue((__bridge CFStringRef)SQRLShipItInstallationAttemptsKey, (__bridge CFPropertyListRef)@(attempts), (__bridge CFStringRef)applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
-	return CFPreferencesSynchronize((__bridge CFStringRef)applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
-}
-
-static BOOL clearInstallationAttempts(NSString *applicationIdentifier) {
-	CFPreferencesSetValue((__bridge CFStringRef)SQRLShipItInstallationAttemptsKey, NULL, (__bridge CFStringRef)applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
-	return CFPreferencesSynchronize((__bridge CFStringRef)applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
-}
-
 // Waits for all instances of the target application (as described in the
-// `request`) to exit, then sends completed.
-static RACSignal *waitForTerminationIfNecessary(SQRLShipItRequest *request) {
+// `state`) to exit, then sends completed.
+static RACSignal *waitForTerminationIfNecessary(SQRLShipItState *state) {
 	return [[RACSignal
 		defer:^{
-			if (request.bundleIdentifier == nil) return [RACSignal empty];
+			if (state.bundleIdentifier == nil) return [RACSignal empty];
 
-			SQRLTerminationListener *listener = [[SQRLTerminationListener alloc] initWithURL:request.targetBundleURL bundleIdentifier:request.bundleIdentifier];
+			SQRLTerminationListener *listener = [[SQRLTerminationListener alloc] initWithURL:state.targetBundleURL bundleIdentifier:state.bundleIdentifier];
 			return [listener waitForTermination];
 		}]
 		setNameWithFormat:@"waitForTerminationIfNecessary"];
 }
 
-static void installRequest(RACSignal *readRequestSignal, NSString *applicationIdentifier) {
-	[[[[[readRequestSignal
-		flattenMap:^(SQRLShipItRequest *request) {
-			return waitForTerminationIfNecessary(request);
-		}]
-		ignoreValues]
-		concat:readRequestSignal]
-		flattenMap:^(SQRLShipItRequest *request) {
-			SQRLInstaller *installer = [[SQRLInstaller alloc] initWithApplicationIdentifier:applicationIdentifier];
-
-			NSUInteger attempt = installationAttempts(applicationIdentifier) + 1;
-			setInstallationAttempts(applicationIdentifier, attempt);
-
-			RACSignal *action;
-			if (attempt > SQRLShipItMaximumInstallationAttempts) {
-				action = [[[[installer.abortInstallationCommand
-					execute:request]
-					initially:^{
-						NSLog(@"Too many attempts to install, aborting update");
-					}]
-					catch:^(NSError *error) {
-						NSLog(@"Error aborting installation: %@", error);
-
-						// Exit successfully so launchd doesn't restart us
-						// again.
-						return [RACSignal empty];
-					}]
-					concat:[RACSignal return:request]];
-			} else {
-				action = [[[[installer.installUpdateCommand
-					execute:request]
-					initially:^{
-						BOOL freshInstall = (attempt == 1);
-						if (freshInstall) {
-							NSLog(@"Beginning installation");
-						} else {
-							NSLog(@"Resuming installation attempt %i", (int)attempt);
-						}
-					}]
-					doCompleted:^{
-						NSLog(@"Installation completed successfully");
-					}]
-					sqrl_addTransactionWithName:NSLocalizedString(@"Updating", nil) description:NSLocalizedString(@"%@ is being updated, and interrupting the process could corrupt the application", nil), request.targetBundleURL.path];
-			}
-
-			// Clear the installation attempts for a successful abort or
-			// install.
-			action = [action doCompleted:^{
-				clearInstallationAttempts(applicationIdentifier);
-			}];
-
-			if (request.launchAfterInstallation) {
-				// Launch regardless of whether installation succeeds or fails.
-				action = [[action
-					deliverOn:RACScheduler.mainThreadScheduler]
-					doNext:^(SQRLShipItRequest *finalRequest) {
-						NSURL *bundleURL = finalRequest.targetBundleURL;
-						if (bundleURL == nil) {
-							NSLog(@"Missing target bundle URL, cannot launch application");
-							return;
-						}
-
-						NSError *error;
-						if (![NSWorkspace.sharedWorkspace launchApplicationAtURL:bundleURL options:NSWorkspaceLaunchDefault configuration:@{} error:&error]) {
-							NSLog(@"Could not launch application at %@: %@", bundleURL, error);
-							return;
-						}
-
-						NSLog(@"Application launched at %@", bundleURL);
-					}];
-			}
-
-			return action;
-		}]
-		subscribeError:^(NSError *error) {
-			NSLog(@"Installation error: %@", error);
-			exit(EXIT_FAILURE);
-		} completed:^{
-			exit(EXIT_SUCCESS);
-		}];
-}
-
 int main(int argc, const char * argv[]) {
 	@autoreleasepool {
 		atexit_b(^{
 			NSLog(@"ShipIt quitting");
 		});
 
-		if (argc < 3) {
-			NSLog(@"Missing launchd job label or state path for ShipIt");
+		if (argc < 2) {
+			NSLog(@"Missing launchd job label for ShipIt");
 			return EXIT_FAILURE;
 		}
 
-		char const *jobLabel = argv[1];
-		const char *statePath = argv[2];
-		NSURL *shipItStateURL = [NSURL fileURLWithPath:@(statePath)];
-		installRequest([SQRLShipItRequest readUsingURL:[RACSignal return:shipItStateURL]], @(jobLabel));
+		const char *jobLabel = argv[1];
+		SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:@(jobLabel)];
+		RACSignal *stateLocation = directoryManager.shipItStateURL;
+
+		[[[[[[[SQRLShipItState
+			readUsingURL:stateLocation]
+			flattenMap:^(SQRLShipItState *state) {
+				return waitForTerminationIfNecessary(state);
+			}]
+			ignoreValues]
+			// Read the latest state, in case it was modified by the
+			// controlling application in the meantime.
+			concat:[SQRLShipItState readUsingURL:stateLocation]]
+			catch:^(NSError *error) {
+				NSLog(@"Error reading saved installer state: %@", error);
+
+				// Exit successfully so launchd doesn't restart us again.
+				return [RACSignal empty];
+			}]
+			flattenMap:^(SQRLShipItState *state) {
+				BOOL freshInstall = (state.installerState == SQRLInstallerStateNothingToDo);
+				SQRLInstaller *installer = [[SQRLInstaller alloc] initWithDirectoryManager:directoryManager];
+
+				NSUInteger attempt = (freshInstall ? 1 : state.installationStateAttempt + 1);
+				RACSignal *action;
+
+				if (attempt > SQRLShipItMaximumInstallationAttempts) {
+					action = [[RACSignal
+						defer:^{
+							NSLog(@"Too many attempts to install from state %i, aborting update", (int)state.installerState);
+
+							return [installer abortInstallationWithState:state];
+						}]
+						catch:^(NSError *error) {
+							NSLog(@"Error aborting installation: %@", error);
+
+							// Exit successfully so launchd doesn't restart us again.
+							return [RACSignal empty];
+						}];
+				} else {
+					action = [[[[RACSignal
+						defer:^{
+							if (freshInstall) {
+								NSLog(@"Beginning installation");
+								state.installerState = SQRLInstallerStateClearingQuarantine;
+							} else {
+								NSLog(@"Resuming installation from state %i", (int)state.installerState);
+							}
+
+							state.installationStateAttempt = attempt;
+
+							return [state writeUsingURL:stateLocation];
+						}]
+						concat:[installer installUpdateWithState:state]]
+						doCompleted:^{
+							NSLog(@"Installation completed successfully");
+						}]
+						sqrl_addTransactionWithName:NSLocalizedString(@"Updating", nil) description:NSLocalizedString(@"%@ is being updated, and interrupting the process could corrupt the application", nil), state.targetBundleURL.path];
+				}
+
+				if (state.relaunchAfterInstallation) {
+					// Relaunch regardless of whether installation succeeds or
+					// fails.
+					action = [[action
+						deliverOn:RACScheduler.mainThreadScheduler]
+						doFinished:^{
+							NSURL *bundleURL = state.targetBundleURL;
+							if (bundleURL == nil) {
+								NSLog(@"Missing target bundle URL, cannot relaunch application");
+								return;
+							}
+
+							NSError *error = nil;
+							if (![NSWorkspace.sharedWorkspace launchApplicationAtURL:bundleURL options:NSWorkspaceLaunchDefault configuration:nil error:&error]) {
+								NSLog(@"Could not relaunch application at %@: %@", bundleURL, error);
+								return;
+							}
+
+							NSLog(@"Application relaunched at %@", bundleURL);
+						}];
+				}
+
+				return action;
+			}]
+			subscribeError:^(NSError *error) {
+				NSLog(@"Installation error: %@", error);
+				exit(EXIT_FAILURE);
+			} completed:^{
+				exit(EXIT_SUCCESS);
+			}];
 
 		dispatch_main();
 	}
 
 	return EXIT_SUCCESS;
 }
+

Squirrel/Squirrel-Info.plist

@@ -9,7 +9,7 @@
 	<key>CFBundleIconFile</key>
 	<string></string>
 	<key>CFBundleIdentifier</key>
-	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<string>com.github.${PRODUCT_NAME:rfc1034identifier}</string>
 	<key>CFBundleInfoDictionaryVersion</key>
 	<string>6.0</string>
 	<key>CFBundleName</key>

Squirrel/Squirrel-Prefix.pch

@@ -0,0 +1,8 @@
+//
+// Prefix header for all source files of the 'Squirrel' target in the 'Squirrel' project
+//
+
+#ifdef __OBJC__
+	#import <Cocoa/Cocoa.h>
+    #import <SystemConfiguration/SystemConfiguration.h>
+#endif

Squirrel/Squirrel.h

@@ -6,14 +6,6 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Foundation/Foundation.h>
-
-//! Project version number for Squirrel.
-FOUNDATION_EXPORT double SquirrelVersionNumber;
-
-//! Project version string for Squirrel.
-FOUNDATION_EXPORT const unsigned char SquirrelVersionString[];
-
 #import <Squirrel/NSBundle+SQRLVersionExtensions.h>
 #import <Squirrel/NSProcessInfo+SQRLVersionExtensions.h>
 #import <Squirrel/SQRLDownloadedUpdate.h>

Squirrel/en.lproj/InfoPlist.strings

@@ -0,0 +1,2 @@
+/* Localized versions of Info.plist keys */
+

SquirrelTests/NSHTTPURLResponseExtensionsSpec.m

@@ -0,0 +1,23 @@
+//
+//  NSHTTPURLResponseExtensionsSpec.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 04/12/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "NSHTTPURLResponse+SQRLExtensions.h"
+
+SpecBegin(NSHTTPURLResponseExtensions)
+
+it(@"should perform case insensitive key look up", ^{
+	NSDictionary *headers = @{
+		@"ETag": @"foo",
+	};
+	NSHTTPURLResponse *response = [[NSHTTPURLResponse alloc] initWithURL:[NSURL URLWithString:@"http://localhost"] statusCode:200 HTTPVersion:(__bridge NSString *)kCFHTTPVersion1_1 headerFields:headers];
+
+	expect([response sqrl_valueForHTTPHeaderField:@"etag"]).to.equal(@"foo");
+	expect([response sqrl_valueForHTTPHeaderField:@"ETAG"]).to.equal(@"foo");
+});
+
+SpecEnd

SquirrelTests/NSProcessInfoExtensionsSpec.m

@@ -6,35 +6,30 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
-QuickSpecBegin(NSProcessInfoExtensions)
+SpecBegin(NSProcessInfoExtensions)
 
 describe(@"-sqrl_operatingSystemShortVersionString", ^{
 	__block NSString *versionString;
 
 	beforeEach(^{
 		versionString = NSProcessInfo.processInfo.sqrl_operatingSystemShortVersionString;
-		expect(versionString).notTo(beNil());
+		expect(versionString).notTo.beNil();
 	});
 
 	it(@"should follow major.minor.patch format", ^{
 		NSError *error = nil;
 		NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"^[0-9]+(\\.[0-9]+)*$" options:0 error:&error];
-		expect(regex).notTo(beNil());
-		expect(error).to(beNil());
+		expect(regex).notTo.beNil();
+		expect(error).to.beNil();
 
 		NSRange fullRange = NSMakeRange(0, versionString.length);
 		NSRange matchRange = [regex rangeOfFirstMatchInString:versionString options:0 range:fullRange];
-		expect(@(NSEqualRanges(matchRange, fullRange))).to(beTruthy());
+		expect(NSEqualRanges(matchRange, fullRange)).to.beTruthy();
 	});
 
 	it(@"should be numerically comparable", ^{
-		expect(@([@"10.6.9" compare:versionString options:NSNumericSearch])).to(equal(@(NSOrderedAscending)));
+		expect([@"10.6.9" compare:versionString options:NSNumericSearch]).to.equal(NSOrderedAscending);
 	});
 });
 
-QuickSpecEnd
+SpecEnd

SquirrelTests/SQRLCodeSignatureVerifierSpec.m

@@ -6,16 +6,9 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
 #import "SQRLCodeSignature.h"
 
-#import "QuickSpec+SQRLFixtures.h"
-
-QuickSpecBegin(SQRLCodeSignatureSpec)
+SpecBegin(SQRLCodeSignature)
 
 __block NSBundle *bundle;
 __block void (^corruptURL)(NSURL *URL);
@@ -24,26 +17,26 @@ beforeEach(^{
 	bundle = self.testApplicationBundle;
 
 	corruptURL = ^(NSURL *URL) {
-		expect(@([@"this bundle is corrupted, yo" writeToURL:bundle.executableURL atomically:YES encoding:NSUTF8StringEncoding error:NULL])).to(beTruthy());
+		expect([@"this bundle is corrupted, yo" writeToURL:bundle.executableURL atomically:YES encoding:NSUTF8StringEncoding error:NULL]).to.beTruthy();
 	};
 });
 
 it(@"should verify a valid bundle", ^{
 	NSError *error = nil;
 	BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
 });
 
 it(@"should fail to verify with different code signing requirements", ^{
 	NSError *error = nil;
-	SQRLCodeSignature *signature = [SQRLCodeSignature currentApplicationSignature:&error];
-	expect(signature).notTo(beNil());
-	expect(error).to(beNil());
+	SQRLCodeSignature *verifier = [SQRLCodeSignature currentApplicationSignature:&error];
+	expect(verifier).notTo.beNil();
+	expect(error).to.beNil();
 
-	BOOL success = [[signature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-	expect(@(success)).to(beFalsy());
-	expect(error).notTo(beNil());
+	BOOL success = [[verifier verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
+	expect(success).to.beFalsy();
+	expect(error).notTo.beNil();
 });
 
 describe(@"code signature changes", ^{
@@ -54,15 +47,15 @@ describe(@"code signature changes", ^{
 	});
 
 	it(@"should fail to verify a bundle with a missing code signature", ^{
-		expect(@([NSFileManager.defaultManager removeItemAtURL:codeSignatureURL error:NULL])).to(beTruthy());
+		expect([NSFileManager.defaultManager removeItemAtURL:codeSignatureURL error:NULL]).to.beTruthy();
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 
 	it(@"should fail to verify a bundle with a corrupt code signature", ^{
@@ -70,25 +63,25 @@ describe(@"code signature changes", ^{
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 });
 
 describe(@"main executable changes", ^{
 	it(@"should fail to verify a bundle with a missing executable", ^{
-		expect(@([NSFileManager.defaultManager removeItemAtURL:bundle.executableURL error:NULL])).to(beTruthy());
+		expect([NSFileManager.defaultManager removeItemAtURL:bundle.executableURL error:NULL]).to.beTruthy();
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorCouldNotCreateStaticCode);
 	});
 
 	it(@"should fail to verify a bundle with a corrupt executable", ^{
@@ -96,11 +89,11 @@ describe(@"main executable changes", ^{
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 });
 
@@ -109,19 +102,19 @@ describe(@"helper executable changes", ^{
 
 	beforeEach(^{
 		helperURL = [bundle URLForAuxiliaryExecutable:@"unused-helper"];
-		expect(helperURL).notTo(beNil());
+		expect(helperURL).notTo.beNil();
 	});
 
 	it(@"should fail to verify a bundle with a missing helper", ^{
-		expect(@([NSFileManager.defaultManager removeItemAtURL:helperURL error:NULL])).to(beTruthy());
+		expect([NSFileManager.defaultManager removeItemAtURL:helperURL error:NULL]).to.beTruthy();
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 
 	it(@"should fail to verify a bundle with a corrupt helper", ^{
@@ -129,11 +122,11 @@ describe(@"helper executable changes", ^{
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 });
 
@@ -142,19 +135,19 @@ describe(@"resource changes", ^{
 
 	beforeEach(^{
 		resourceURL = [bundle URLForResource:@"MainMenu" withExtension:@"nib"];
-		expect(resourceURL).notTo(beNil());
+		expect(resourceURL).notTo.beNil();
 	});
 
 	it(@"should fail to verify a bundle with a missing resource", ^{
-		expect(@([NSFileManager.defaultManager removeItemAtURL:resourceURL error:NULL])).to(beTruthy());
+		expect([NSFileManager.defaultManager removeItemAtURL:resourceURL error:NULL]).to.beTruthy();
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 
 	it(@"should fail to verify a bundle with a corrupt resource", ^{
@@ -162,11 +155,11 @@ describe(@"resource changes", ^{
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 });
 
@@ -178,15 +171,15 @@ describe(@"framework changes", ^{
 	});
 
 	it(@"should fail to verify a bundle with a missing framework", ^{
-		expect(@([NSFileManager.defaultManager removeItemAtURL:frameworkURL error:NULL])).to(beTruthy());
+		expect([NSFileManager.defaultManager removeItemAtURL:frameworkURL error:NULL]).to.beTruthy();
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 
 	it(@"should fail to verify a bundle with a corrupt framework", ^{
@@ -194,12 +187,12 @@ describe(@"framework changes", ^{
 
 		NSError *error = nil;
 		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:bundle.bundleURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beFalsy());
+		expect(success).to.beFalsy();
 
-		expect(error).notTo(beNil());
-		expect(error.domain).to(equal(SQRLCodeSignatureErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLCodeSignatureErrorDidNotPass)));
+		expect(error).notTo.beNil();
+		expect(error.domain).to.equal(SQRLCodeSignatureErrorDomain);
+		expect(error.code).to.equal(SQRLCodeSignatureErrorDidNotPass);
 	});
 });
 
-QuickSpecEnd
+SpecEnd

SquirrelTests/SQRLDeepCodesignSpec.m

@@ -0,0 +1,119 @@
+//
+//  SQRLDeepCodesignSpec.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 2013-09-05.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+SpecBegin(SQRLDeepCodesign)
+
+NSMutableDictionary * (^environmentSuitableForChildProcess)(void) = ^ {
+	// Remove environment variables that configure the Obj-C runtime
+	// Specifically OBJC_DISABLE_GC so that child processes aren't forced to
+	// adopt the GC preference of the test suite
+	NSMutableDictionary *environment = [NSProcessInfo.processInfo.environment mutableCopy];
+	NSSet *objcEnvironmentVariables = [environment keysOfEntriesPassingTest:^(NSString *variable, id obj, BOOL *stop) {
+		return [variable hasPrefix:@"OBJC"];
+	}];
+	[environment removeObjectsForKeys:objcEnvironmentVariables.allObjects];
+	return environment;
+};
+
+NSTask * (^codesignTaskWithArguments)(NSArray *) = ^ (NSArray *arguments) {
+	NSTask *task = [[NSTask alloc] init];
+	task.launchPath = @"/usr/bin/xcrun";
+	task.arguments = [@[ @"codesign" ] arrayByAddingObjectsFromArray:arguments];
+	task.environment = environmentSuitableForChildProcess();
+	return task;
+};
+
+void (^resignTestApplicationPreserveEverythingButTheRequirements)(void) = ^{
+	NSURL *testApplicationLocation = self.testApplicationURL;
+
+	NSTask *resignCodesignTask = codesignTaskWithArguments(@[
+		@"--sign", @"-",
+		@"--force",
+		@"--verbose=4",
+		@"--preserve-metadata=identifier,entitlements,resource-rules",
+		testApplicationLocation.path,
+	]);
+
+	[resignCodesignTask launch];
+	[resignCodesignTask waitUntilExit];
+
+	expect(resignCodesignTask.terminationStatus).to.equal(0);
+};
+
+void (^deepCodesignTestApplication)(void) = ^{
+	NSURL *testApplicationLocation = self.testApplicationURL;
+
+	NSBundle *testsBundle = [NSBundle bundleForClass:self.class];
+	NSURL *deepCodesignLocation = [testsBundle URLForResource:@"deep-codesign" withExtension:nil];
+
+	NSNumber *executable = nil;
+	NSError *executableError = nil;
+	BOOL getExecutable = [deepCodesignLocation getResourceValue:&executable forKey:NSURLIsExecutableKey error:&executableError];
+	expect(getExecutable).to.beTruthy();
+	expect(executable.boolValue).to.beTruthy();
+	expect(executableError).to.beNil();
+
+	NSTask *deepCodesignTask = [[NSTask alloc] init];
+	deepCodesignTask.launchPath = deepCodesignLocation.path;
+	deepCodesignTask.standardError = [NSPipe pipe];
+	deepCodesignTask.standardOutput = [NSPipe pipe];
+
+	NSMutableDictionary *environment = environmentSuitableForChildProcess();
+	[environment addEntriesFromDictionary:@{
+		@"CODE_SIGN_IDENTITY": @"-",
+		@"CONFIGURATION_BUILD_DIR": testApplicationLocation.URLByDeletingLastPathComponent.path,
+		@"FULL_PRODUCT_NAME": testApplicationLocation.lastPathComponent,
+	}];
+
+	deepCodesignTask.environment = environment;
+
+	[deepCodesignTask launch];
+	[deepCodesignTask waitUntilExit];
+
+	expect(deepCodesignTask.terminationStatus).to.equal(0);
+
+	/*
+		By signing test application's contents, which are covered by test
+		application's ResourceRules it's signature becomes invalid. Usually,
+		Xcode would sign the application after deep-codesign has run so the
+		signature would include the _signed_ child resources which are covered
+		by test application's ResourceRules
+
+		test application is already signed, so we need to manually resign it
+
+		deep-codesign preserves the requirements, we can't use it to resign the
+		root target, the new signing identity wouldn't verify against the
+		original designated requirement
+	 */
+	resignTestApplicationPreserveEverythingButTheRequirements();
+};
+
+BOOL (^deepVerify)(void) = ^ BOOL {
+	NSTask *deepVerifyTask = codesignTaskWithArguments(@[
+		@"--deep-verify",
+		@"--verbose=4",
+		self.testApplicationURL.path
+	]);
+
+	[deepVerifyTask launch];
+	[deepVerifyTask waitUntilExit];
+
+	return deepVerifyTask.terminationStatus == 0;
+};
+
+it(@"should deep sign the test application", ^{
+	deepCodesignTestApplication();
+});
+
+xit(@"should deep verify after signing", ^{
+	expect(deepVerify()).to.beFalsy();
+	deepCodesignTestApplication();
+	expect(deepVerify()).to.beTruthy();
+});
+
+SpecEnd

SquirrelTests/SQRLDirectoryManagerSpec.m

@@ -6,44 +6,39 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
 #import "SQRLDirectoryManager.h"
 
-QuickSpecBegin(SQRLDirectoryManagerSpec)
+SpecBegin(SQRLDirectoryManager)
 
 __block NSString *otestIdentifier;
 
 beforeEach(^{
-	otestIdentifier = NSProcessInfo.processInfo.environment[@"FORCE_APP_IDENTIFIER"];
-	expect(otestIdentifier).notTo(beNil());
+	otestIdentifier = NSRunningApplication.currentApplication.localizedName;
+	expect(otestIdentifier).notTo.beNil();
 });
 
 it(@"should initialize", ^{
 	SQRLDirectoryManager *manager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:otestIdentifier];
-	expect(manager).notTo(beNil());
+	expect(manager).notTo.beNil();
 });
 
 it(@"should create a manager for the current app", ^{
 	SQRLDirectoryManager *manager = SQRLDirectoryManager.currentApplicationManager;
-	expect(manager).notTo(beNil());
-	expect(manager).to(equal([[SQRLDirectoryManager alloc] initWithApplicationIdentifier:otestIdentifier]));
+	expect(manager).notTo.beNil();
+	expect(manager).to.equal([[SQRLDirectoryManager alloc] initWithApplicationIdentifier:otestIdentifier]);
 });
 
 it(@"should send an Application Support URL", ^{
 	SQRLDirectoryManager *manager = SQRLDirectoryManager.currentApplicationManager;
 
 	NSError *error = nil;
-	NSURL *appSupportURL = [[manager storageURL] firstOrDefault:nil success:NULL error:&error];
-	expect(appSupportURL).notTo(beNil());
-	expect(error).to(beNil());
+	NSURL *appSupportURL = [[manager applicationSupportURL] firstOrDefault:nil success:NULL error:&error];
+	expect(appSupportURL).notTo.beNil();
+	expect(error).to.beNil();
 
 	__block BOOL directory = NO;
-	expect(@([NSFileManager.defaultManager fileExistsAtPath:appSupportURL.path isDirectory:&directory])).to(beTruthy());
-	expect(@(directory)).to(beTruthy());
+	expect([NSFileManager.defaultManager fileExistsAtPath:appSupportURL.path isDirectory:&directory]).to.beTruthy();
+	expect(directory).to.beTruthy();
 });
 
 it(@"should send a ShipIt state URL", ^{
@@ -51,8 +46,8 @@ it(@"should send a ShipIt state URL", ^{
 
 	NSError *error = nil;
 	NSURL *stateURL = [[manager shipItStateURL] firstOrDefault:nil success:NULL error:&error];
-	expect(stateURL).notTo(beNil());
-	expect(error).to(beNil());
+	expect(stateURL).notTo.beNil();
+	expect(error).to.beNil();
 });
 
-QuickSpecEnd
+SpecEnd

SquirrelTests/SQRLDownloadManagerSpec.m

@@ -0,0 +1,87 @@
+//
+//  SQRLDownloadControllerSpec.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 27/09/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLDownloadManager.h"
+#import "SQRLResumableDownload.h"
+#import "NSError+SQRLVerbosityExtensions.h"
+#import <ReactiveCocoa/ReactiveCocoa.h>
+
+SpecBegin(SQRLDownloadManager)
+
+__block SQRLDownloadManager *downloadManager = nil;
+
+beforeAll(^{
+	downloadManager = SQRLDownloadManager.defaultDownloadManager;
+
+	NSError *removeError = nil;
+	BOOL remove = [[downloadManager removeAllResumableDownloads] waitUntilCompleted:&removeError];
+	if (!remove) {
+		if ([removeError.domain isEqualToString:NSCocoaErrorDomain] && removeError.code == NSFileNoSuchFileError) return;
+		
+		NSLog(@"Couldn’t remove resumable downloads %@", removeError.sqrl_verboseDescription);
+	}
+});
+
+NSURL * (^newTestURL)() = ^ () {
+	return [[NSURL alloc] initWithScheme:@"http" host:@"localhost" path:[@"/" stringByAppendingString:NSProcessInfo.processInfo.globallyUniqueString]];
+};
+
+NSURL * (^newDownloadURL)() = ^ () {
+	NSError *error = nil;
+	SQRLResumableDownload *download = [[downloadManager downloadForRequest:[NSURLRequest requestWithURL:newTestURL()]] firstOrDefault:nil success:NULL error:&error];
+	expect(download).notTo.beNil();
+	expect(error).to.beNil();
+
+	NSURL *downloadURL = download.fileURL;
+	expect(downloadURL).notTo.beNil();
+
+	return downloadURL;
+};
+
+it(@"should return a file that doesn't exist yet for new URLs", ^{
+	NSURL *downloadURL = newDownloadURL();
+
+	BOOL exists = [NSFileManager.defaultManager fileExistsAtPath:downloadURL.path];
+	expect(exists).to.beFalsy();
+});
+
+it(@"should return a path in a writable directory for new URLs", ^{
+	NSURL *downloadURL = newDownloadURL();
+
+	BOOL writable = [NSFileManager.defaultManager isWritableFileAtPath:downloadURL.URLByDeletingLastPathComponent.path];
+	expect(writable).to.beTruthy();
+});
+
+it(@"should return the same path for the same URL", ^{
+	NSURL *testURL = newTestURL();
+
+	SQRLDownload *download1 = [[downloadManager downloadForRequest:[NSURLRequest requestWithURL:testURL]] first];
+	SQRLDownload *download2 = [[downloadManager downloadForRequest:[NSURLRequest requestWithURL:testURL]] first];
+	expect(download1).notTo.beNil();
+	expect(download1).to.equal(download2);
+});
+
+it(@"should remember a response", ^{
+	NSURLRequest *request = [NSURLRequest requestWithURL:newTestURL()];
+	NSHTTPURLResponse *response = [[NSHTTPURLResponse alloc] initWithURL:request.URL statusCode:200 HTTPVersion:(__bridge NSString *)kCFHTTPVersion1_1 headerFields:@{ @"ETag": NSProcessInfo.processInfo.globallyUniqueString }];
+
+	SQRLDownload *initialDownload = [[downloadManager downloadForRequest:request] first];
+
+	SQRLResumableDownload *newDownload = [[SQRLResumableDownload alloc] initWithRequest:request response:response fileURL:initialDownload.fileURL];
+	expect(newDownload).notTo.equal(initialDownload);
+
+	NSError *error = nil;
+	BOOL setNewDownload = [[downloadManager setDownload:newDownload forRequest:request] waitUntilCompleted:&error];
+	expect(setNewDownload).to.beTruthy();
+	expect(error).to.beNil();
+
+	SQRLResumableDownload *resumedDownload = [[downloadManager downloadForRequest:request] first];
+	expect(newDownload).to.equal(resumedDownload);
+});
+
+SpecEnd

SquirrelTests/SQRLDownloadedUpdateSpec.m

@@ -0,0 +1,40 @@
+//
+//  SQRLDownloadedUpdateSpec.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 04/12/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+SpecBegin(SQRLDownloadedUpdate)
+
+it(@"should serialise to JSON", ^{
+	NSError *error = nil;
+	SQRLUpdate *update = [SQRLUpdate modelWithDictionary:@{
+		@keypath(SQRLUpdate.new, updateURL) : [NSURL URLWithString:@"http://fake.domain/path"],
+	} error:&error];
+	expect(update).notTo.beNil();
+
+	NSURL *testApplicationURL = [self createTestApplicationUpdate];
+	NSBundle *testApplicationBundle = [NSBundle bundleWithURL:testApplicationURL];
+	expect(testApplicationBundle).notTo.beNil();
+
+	SQRLDownloadedUpdate *downloadedUpdate = [[SQRLDownloadedUpdate alloc] initWithUpdate:update bundle:testApplicationBundle];
+	expect(downloadedUpdate).notTo.beNil();
+
+	NSDictionary *JSONDictionary = [MTLJSONAdapter JSONDictionaryFromModel:downloadedUpdate];
+	expect(JSONDictionary).notTo.beNil();
+
+	NSData *JSONData = [NSJSONSerialization dataWithJSONObject:JSONDictionary options:0 error:&error];
+	expect(JSONData).notTo.beNil();
+	expect(error).to.beNil();
+
+	JSONDictionary = [NSJSONSerialization JSONObjectWithData:JSONData options:0 error:&error];
+	expect(JSONDictionary).notTo.beNil();
+
+	SQRLDownloadedUpdate *downloadedUpdate2 = [MTLJSONAdapter modelOfClass:SQRLDownloadedUpdate.class fromJSONDictionary:JSONDictionary error:&error];
+	expect(downloadedUpdate2).to.equal(downloadedUpdate);
+	expect(error).to.beNil();
+});
+
+SpecEnd

SquirrelTests/SQRLHTTPServer.h

@@ -0,0 +1,18 @@
+//
+//  SQRLHTTPServer.h
+//  Squirrel
+//
+//  Created by Keith Duncan on 03/12/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+@interface SQRLHTTPServer : NSObject
+
+- (NSURL *)start:(NSError **)errorRef;
+- (void)invalidate;
+
+@property (copy, nonatomic) CFHTTPMessageRef (^responseBlock)(CFHTTPMessageRef request);
+
+@end

SquirrelTests/SQRLHTTPServer.m

@@ -0,0 +1,165 @@
+//
+//  SQRLHTTPServer.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 03/12/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLHTTPServer.h"
+
+#import <sys/socket.h>
+#import <netinet/in.h>
+
+@interface SQRLHTTPServer ()
+@property (assign, nonatomic) dispatch_source_t listenerSource;
+@property (strong, nonatomic) NSMutableArray *cleanupBlocks;
+@end
+
+@implementation SQRLHTTPServer
+
+- (id)init {
+	self = [super init];
+	if (self == nil) return nil;
+
+	_cleanupBlocks = [[NSMutableArray alloc] init];
+
+	return self;
+}
+
+- (void)dealloc {
+	[self invalidate];
+}
+
+- (NSURL *)start:(NSError **)errorRef {
+	NSParameterAssert(self.listenerSource == NULL);
+
+	int listenSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+
+	struct sockaddr_in listenAddress = {
+		.sin_len = sizeof(listenAddress),
+		.sin_family = AF_INET,
+		.sin_port = 0,
+		.sin_addr = {
+			.s_addr = htonl(INADDR_LOOPBACK),
+		},
+	};
+	int bindError = bind(listenSocket, (struct sockaddr const *)&listenAddress, listenAddress.sin_len);
+	if (bindError != 0) {
+		close(listenSocket);
+
+		if (errorRef != NULL) *errorRef = [NSError errorWithDomain:NSPOSIXErrorDomain code:bindError userInfo:nil];
+		return nil;
+	}
+
+	listen(listenSocket, 128);
+
+	dispatch_source_t source = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, listenSocket, 0, NULL);
+	dispatch_source_set_event_handler(source, ^{
+		int connectionSocket = accept(listenSocket, NULL, NULL);
+		// Wait to close the connection until after the test case is complete.
+		// We need NSURLConnection to timeout, closing the connection causes it
+		// to error immediately.
+		[self addCleanupBlock:^{
+			close(connectionSocket);
+		}];
+
+		CFHTTPMessageRef request = (__bridge CFHTTPMessageRef)CFBridgingRelease(CFHTTPMessageCreateEmpty(kCFAllocatorDefault, true));
+
+		while (1) {
+			uint8_t buffer;
+			ssize_t readLength = read(connectionSocket, &buffer, 1);
+			if (readLength < 0) {
+				return;
+			}
+
+			CFHTTPMessageAppendBytes(request, (UInt8 const *)&buffer, readLength);
+			if (!CFHTTPMessageIsHeaderComplete(request)) {
+				continue;
+			}
+
+			// Doesn't support reading requests with a body for simplicity
+			NSString *contentLength = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("Content-Length")));
+			if (contentLength != nil) {
+				return;
+			}
+
+			break;
+		}
+
+		NSLog(@"Received Request:");
+		NSLog(@"%@", [[NSString alloc] initWithData:CFBridgingRelease(CFHTTPMessageCopySerializedMessage(request)) encoding:NSASCIIStringEncoding]);
+
+		CFHTTPMessageRef response = self.responseBlock(request);
+		NSData *responseData = CFBridgingRelease(CFHTTPMessageCopySerializedMessage(response));
+
+		NSLog(@"Sending Response:");
+		NSLog(@"%@", [[NSString alloc] initWithData:responseData encoding:NSASCIIStringEncoding]);
+
+		size_t bufferLength = responseData.length;
+		uint8_t const *buffer = responseData.bytes;
+
+		while (1) {
+			ssize_t writeLength = write(connectionSocket, buffer, bufferLength);
+			if (writeLength < 0) {
+				return;
+			}
+
+			buffer += writeLength;
+			bufferLength -= writeLength;
+
+			if (bufferLength == 0) {
+				break;
+			}
+		}
+	});
+	dispatch_source_set_cancel_handler(source, ^{
+		close(listenSocket);
+	});
+	dispatch_resume(source);
+
+	struct sockaddr_storage localAddress = {};
+	socklen_t localAddressLength = sizeof(localAddress);
+	int localAddressError = getsockname(listenSocket, (struct sockaddr *)&localAddress, &localAddressLength);
+	if (localAddressError != 0) {
+		dispatch_release(source);
+
+		if (errorRef != NULL) *errorRef = [NSError errorWithDomain:NSPOSIXErrorDomain code:localAddressError userInfo:nil];
+		return nil;
+	}
+
+	self.listenerSource = source;
+
+	// IPv4 and IPv6 address transport layer port fields are at the same offset
+	// and are the same size
+	in_port_t port = ntohs(((struct sockaddr_in *)&localAddress)->sin_port);
+
+	return [NSURL URLWithString:[NSString stringWithFormat:@"http://localhost:%ld/", (unsigned long)port]];
+}
+
+- (void)invalidate {
+	dispatch_source_t listenerSource = self.listenerSource;
+	if (listenerSource == NULL) return;
+
+	dispatch_source_cancel(listenerSource);
+	dispatch_release(listenerSource);
+
+	self.listenerSource = NULL;
+
+	[self performCleanup];
+}
+
+- (void)addCleanupBlock:(void (^)(void))block {
+	[self.cleanupBlocks addObject:[block copy]];
+}
+
+- (void)performCleanup {
+	NSArray *blocks = [self.cleanupBlocks copy];
+	[self.cleanupBlocks removeAllObjects];
+
+	for (void (^currentBlock)(void) in blocks) {
+		currentBlock();
+	}
+}
+
+@end

SquirrelTests/SQRLInstallerSpec.m

@@ -6,32 +6,13 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
 #import "SQRLCodeSignature.h"
 #import "SQRLDirectoryManager.h"
-#import "SQRLInstaller+Private.h"
-#import "SQRLInstallerOwnedBundle.h"
-#import "SQRLShipItRequest.h"
+#import "SQRLInstaller.h"
+#import "SQRLShipItLauncher.h"
+#import "SQRLShipItState.h"
 
-#import "QuickSpec+SQRLFixtures.h"
-
-QuickSpecBegin(SQRLInstallerSpec)
-
-mode_t (^modeOfURL)(NSURL *) = ^ mode_t (NSURL *fileURL) {
-	NSFileSecurity *fileSecurity = nil;
-	BOOL success = [fileURL getResourceValue:&fileSecurity forKey:NSURLFileSecurityKey error:NULL];
-	expect(@(success)).to(beTruthy());
-	expect(fileSecurity).notTo(beNil());
-
-	__block mode_t mode;
-	expect(@(CFFileSecurityGetMode((__bridge CFFileSecurityRef)fileSecurity, &mode))).to(beTruthy());
-
-	return mode & (S_IRWXU | S_IRWXG | S_IRWXO);
-};
+SpecBegin(SQRLInstaller)
 
 __block NSURL *updateURL;
 
@@ -39,148 +20,127 @@ beforeEach(^{
 	updateURL = [self createTestApplicationUpdate];
 });
 
-it(@"should install an update using ShipIt", ^{
-	SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:self.testApplicationURL bundleIdentifier:nil launchAfterInstallation:NO useUpdateBundleName:NO];
+it(@"should install an update", ^{
+	SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:self.testApplicationURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+	expect([[state writeUsingURL:self.shipItDirectoryManager.shipItStateURL] waitUntilCompleted:NULL]).to.beTruthy();
 
-	[self installWithRequest:request remote:YES];
+	[self launchShipIt];
 
-	expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
-});
-
-it(@"should install an update in process", ^{
-	SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:self.testApplicationURL bundleIdentifier:nil launchAfterInstallation:NO useUpdateBundleName:NO];
-
-	[self installWithRequest:request remote:NO];
-
-	expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
+	expect(self.testApplicationBundleVersion).will.equal(SQRLTestApplicationUpdatedShortVersionString);
 });
 
 it(@"should install an update and relaunch", ^{
 	NSString *bundleIdentifier = @"com.github.Squirrel.TestApplication";
 	NSArray *apps = [NSRunningApplication runningApplicationsWithBundleIdentifier:bundleIdentifier];
-	expect(@(apps.count)).to(equal(@0));
+	expect(apps.count).to.equal(0);
 
-	SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:self.testApplicationURL bundleIdentifier:nil launchAfterInstallation:YES useUpdateBundleName:NO];
+	SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:self.testApplicationURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+	state.relaunchAfterInstallation = YES;
+	expect([[state writeUsingURL:self.shipItDirectoryManager.shipItStateURL] waitUntilCompleted:NULL]).to.beTruthy();
 
-	[self installWithRequest:request remote:YES];
+	[self launchShipIt];
 
-	expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
-	expect(@([NSRunningApplication runningApplicationsWithBundleIdentifier:bundleIdentifier].count)).toEventually(equal(@1));
+	expect(self.testApplicationBundleVersion).will.equal(SQRLTestApplicationUpdatedShortVersionString);
+	expect([NSRunningApplication runningApplicationsWithBundleIdentifier:bundleIdentifier].count).will.equal(1);
 });
 
 it(@"should install an update from another volume", ^{
 	NSURL *diskImageURL = [self createAndMountDiskImageNamed:@"TestApplication 2.1" fromDirectory:updateURL.URLByDeletingLastPathComponent];
 	updateURL = [diskImageURL URLByAppendingPathComponent:updateURL.lastPathComponent];
 
-	SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:self.testApplicationURL bundleIdentifier:nil launchAfterInstallation:NO useUpdateBundleName:NO];
+	SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:self.testApplicationURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+	expect([[state writeUsingURL:self.shipItDirectoryManager.shipItStateURL] waitUntilCompleted:NULL]).to.beTruthy();
 
-	[self installWithRequest:request remote:YES];
+	[self launchShipIt];
 
-	expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
+	expect(self.testApplicationBundleVersion).will.equal(SQRLTestApplicationUpdatedShortVersionString);
 });
 
 it(@"should install an update to another volume", ^{
 	NSURL *diskImageURL = [self createAndMountDiskImageNamed:@"TestApplication" fromDirectory:self.testApplicationURL.URLByDeletingLastPathComponent];
 	NSURL *targetURL = [diskImageURL URLByAppendingPathComponent:self.testApplicationURL.lastPathComponent];
 
-	SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:targetURL bundleIdentifier:nil launchAfterInstallation:NO useUpdateBundleName:NO];
+	SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:targetURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+	expect([[state writeUsingURL:self.shipItDirectoryManager.shipItStateURL] waitUntilCompleted:NULL]).to.beTruthy();
 
-	[self installWithRequest:request remote:YES];
+	[self launchShipIt];
 
 	NSURL *plistURL = [targetURL URLByAppendingPathComponent:@"Contents/Info.plist"];
-	expect([NSDictionary dictionaryWithContentsOfURL:plistURL][SQRLBundleShortVersionStringKey]).withTimeout(SQRLLongTimeout).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
+	expect([NSDictionary dictionaryWithContentsOfURL:plistURL][SQRLBundleShortVersionStringKey]).will.equal(SQRLTestApplicationUpdatedShortVersionString);
 });
 
-describe(@"with backup restoration", ^{
-	__block NSURL *targetURL;
+it(@"should install an update in process", ^{
+	SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:self.testApplicationURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+	state.installerState = SQRLInstallerStateClearingQuarantine;
 
-	beforeEach(^{
-		targetURL = self.testApplicationURL;
+	SQRLInstaller *installer = [[SQRLInstaller alloc] initWithDirectoryManager:SQRLDirectoryManager.currentApplicationManager];
+	expect(installer).notTo.beNil();
 
-		NSURL *copiedTargetURL = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"TestApplication Target.app"];
-		expect(@([NSFileManager.defaultManager moveItemAtURL:targetURL toURL:copiedTargetURL error:NULL])).to(beTruthy());
-
-		SQRLCodeSignature *codeSignature = self.testApplicationSignature;
-
-		SQRLInstallerOwnedBundle *ownedBundle = [[SQRLInstallerOwnedBundle alloc] initWithOriginalURL:targetURL temporaryURL:copiedTargetURL codeSignature:codeSignature];
-		NSData *ownedBundleArchive = [NSKeyedArchiver archivedDataWithRootObject:ownedBundle];
-		expect(ownedBundleArchive).notTo(beNil());
-
-		// Set up ShipIt's preferences like it paused in the middle of an
-		// installation.
-		NSString *applicationIdentifier = self.shipItDirectoryManager.applicationIdentifier;
-
-		CFPreferencesSetValue((__bridge CFStringRef)SQRLShipItInstallationAttemptsKey, (__bridge CFPropertyListRef)@(4), (__bridge CFStringRef)applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
-		CFPreferencesSetValue((__bridge CFStringRef)SQRLInstallerOwnedBundleKey, (__bridge CFDataRef)ownedBundleArchive, (__bridge CFStringRef)applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
-
-		BOOL synchronized = CFPreferencesSynchronize((__bridge CFStringRef)applicationIdentifier, kCFPreferencesCurrentUser, kCFPreferencesCurrentHost);
-		expect(@(synchronized)).to(beTruthy());
-	});
-
-	it(@"should not install an update after too many attempts", ^{
-		SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:targetURL bundleIdentifier:nil launchAfterInstallation:NO useUpdateBundleName:NO];
-		[self installWithRequest:request remote:YES];
-
-		__block NSError *error;
-		expect(@([[self.testApplicationSignature verifyBundleAtURL:targetURL] waitUntilCompleted:&error])).toEventually(beTruthy());
-		expect(error).to(beNil());
-
-		expect(self.testApplicationBundleVersion).to(equal(SQRLTestApplicationOriginalShortVersionString));
-	});
-
-	it(@"should relaunch even after failing to install an update", ^{
-		SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:targetURL bundleIdentifier:nil launchAfterInstallation:YES useUpdateBundleName:NO];
-		[self installWithRequest:request remote:YES];
-
-		expect(@([NSRunningApplication runningApplicationsWithBundleIdentifier:@"com.github.Squirrel.TestApplication"].count)).toEventually(equal(@1));
-
-		__block NSError *error;
-		expect(@([[self.testApplicationSignature verifyBundleAtURL:targetURL] waitUntilCompleted:&error])).to(beTruthy());
-		expect(error).to(beNil());
-
-		expect(self.testApplicationBundleVersion).to(equal(SQRLTestApplicationOriginalShortVersionString));
-	});
+	NSError *installError = nil;
+	BOOL install = [[installer installUpdateWithState:state] asynchronouslyWaitUntilCompleted:&installError];
+	expect(install).to.beTruthy();
+	expect(installError).to.beNil();
 });
 
-it(@"should disallow writing the updated application except by the owner", ^{
-	NSString *command = [NSString stringWithFormat:@"chmod -R 0777 '%@'", updateURL.path];
-	expect(@(system(command.UTF8String))).to(equal(@0));
+it(@"should not install an update after too many attempts", ^{
+	NSURL *targetURL = self.testApplicationURL;
+	NSURL *backupURL = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"TestApplication.app.bak"];
+	expect([NSFileManager.defaultManager moveItemAtURL:targetURL toURL:backupURL error:NULL]).to.beTruthy();
 
-	expect(@(modeOfURL(updateURL))).to(equal(@0777));
-	expect(@(modeOfURL([updateURL URLByAppendingPathComponent:@"Contents/MacOS/TestApplication"]))).to(equal(@0777));
+	SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:targetURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+	state.backupBundleURL = backupURL;
+	state.installerState = SQRLInstallerStateInstalling;
+	state.installationStateAttempt = 4;
+	expect([[state writeUsingURL:self.shipItDirectoryManager.shipItStateURL] waitUntilCompleted:NULL]).to.beTruthy();
 
-	SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:self.testApplicationURL bundleIdentifier:nil launchAfterInstallation:NO useUpdateBundleName:NO];
+	[self launchShipIt];
 
-	[self installWithRequest:request remote:YES];
+	// No update should've been installed, and the application should be
+	// restored from the backup.
+	__block NSError *error = nil;
+	expect([[self.testApplicationSignature verifyBundleAtURL:targetURL] waitUntilCompleted:&error]).will.beTruthy();
+	expect(error).to.beNil();
 
-	expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
+	expect(self.testApplicationBundleVersion).to.equal(SQRLTestApplicationOriginalShortVersionString);
+});
 
-	expect(@(modeOfURL(self.testApplicationURL))).to(equal(@0755));
-	expect(@(modeOfURL([self.testApplicationURL URLByAppendingPathComponent:@"Contents/MacOS/TestApplication"]))).to(equal(@0755));
+it(@"should relaunch even after failing to install an update", ^{
+	NSURL *targetURL = self.testApplicationURL;
+	NSURL *backupURL = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"TestApplication.app.bak"];
+	expect([NSFileManager.defaultManager moveItemAtURL:targetURL toURL:backupURL error:NULL]).to.beTruthy();
+
+	SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:targetURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+	state.backupBundleURL = backupURL;
+	state.installerState = SQRLInstallerStateInstalling;
+	state.installationStateAttempt = 4;
+	state.relaunchAfterInstallation = YES;
+	expect([[state writeUsingURL:self.shipItDirectoryManager.shipItStateURL] waitUntilCompleted:NULL]).to.beTruthy();
+
+	[self launchShipIt];
+
+	__block NSError *error = nil;
+	expect([[self.testApplicationSignature verifyBundleAtURL:targetURL] waitUntilCompleted:&error]).will.beTruthy();
+	expect(error).to.beNil();
+
+	expect([NSRunningApplication runningApplicationsWithBundleIdentifier:@"com.github.Squirrel.TestApplication"].count).will.equal(1);
+	expect(self.testApplicationBundleVersion).to.equal(SQRLTestApplicationOriginalShortVersionString);
 });
 
 describe(@"signal handling", ^{
 	__block NSURL *targetURL;
 
-	void (^verifyUpdate)(void) = ^{
-		// Wait up to the launchd throttle interval, then verify that ShipIt
-		// relaunched and finished installing the update.
-		expect(self.testApplicationBundleVersion).withTimeout(SQRLLongTimeout).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
-
-		NSError *error;
-		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:targetURL] waitUntilCompleted:&error];
-		expect(@(success)).to(beTruthy());
-		expect(error).to(beNil());
-	};
-
 	beforeEach(^{
 		// Copied so that we don't recreate the TestApplication bundle by
 		// accessing the property.
 		targetURL = self.testApplicationURL;
 
-		SQRLShipItRequest *request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:self.testApplicationURL bundleIdentifier:nil launchAfterInstallation:NO useUpdateBundleName:NO];
+		SQRLShipItState *state = [[SQRLShipItState alloc] initWithTargetBundleURL:self.testApplicationURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+		expect([[state writeUsingURL:self.shipItDirectoryManager.shipItStateURL] waitUntilCompleted:NULL]).to.beTruthy();
 
-		[self installWithRequest:request remote:YES];
+		[self launchShipIt];
+
+		// Wait until ShipIt has transitioned by at least one state.
+		expect([[[SQRLShipItState readUsingURL:self.shipItDirectoryManager.shipItStateURL] asynchronousFirstOrDefault:nil success:NULL error:NULL] installerState]).willNot.equal(SQRLInstallerStateNothingToDo);
 
 		// Apply a random delay before sending the termination signal, to
 		// fuzz out race conditions.
@@ -188,42 +148,45 @@ describe(@"signal handling", ^{
 		[NSThread sleepForTimeInterval:delay];
 	});
 
+	afterEach(^{
+		// Wait up to the launchd throttle interval, then verify that ShipIt
+		// relaunched and finished installing the update.
+		Expecta.asynchronousTestTimeout = 5;
+		expect(self.testApplicationBundleVersion).will.equal(SQRLTestApplicationUpdatedShortVersionString);
+
+		NSError *error = nil;
+		BOOL success = [[self.testApplicationSignature verifyBundleAtURL:targetURL] waitUntilCompleted:&error];
+		expect(success).to.beTruthy();
+		expect(error).to.beNil();
+	});
+
 	it(@"should handle SIGHUP", ^{
 		system("killall -HUP ShipIt");
-		verifyUpdate();
 	});
 
 	it(@"should handle SIGTERM", ^{
 		system("killall -TERM ShipIt");
-		verifyUpdate();
 	});
 
 	it(@"should handle SIGINT", ^{
 		system("killall -INT ShipIt");
-		verifyUpdate();
 	});
 
 	it(@"should handle SIGQUIT", ^{
 		system("killall -QUIT ShipIt");
-		verifyUpdate();
 	});
 
 	it(@"should handle SIGKILL", ^{
 		// SIGKILL is unique in that it'll always terminate ShipIt, so send it
-		// a couple times to really test resumption.
-		//
-		// Two SIGKILL signals means that it'll be launched three times (which
-		// matches the maximum number of attempts per state).
-		for (int i = 0; i < 2; i++) {
+		// a few times to really test resumption.
+		for (int i = 0; i < 3; i++) {
 			system("killall -KILL ShipIt");
 
 			// Wait at least for the launchd throttle interval.
 			NSTimeInterval delay = 2 + (arc4random_uniform(100) / 1000.0);
 			[NSThread sleepForTimeInterval:delay];
 		}
-
-		verifyUpdate();
 	});
 });
 
-QuickSpecEnd
+SpecEnd

SquirrelTests/SQRLShipItRequestSpec.m

@@ -1,86 +0,0 @@
-//
-//  SQRLShipItStateSpec.m
-//  Squirrel
-//
-//  Created by Justin Spahr-Summers on 2013-10-09.
-//  Copyright (c) 2013 GitHub. All rights reserved.
-//
-
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
-#import "SQRLDirectoryManager.h"
-#import "SQRLShipItRequest.h"
-
-#import "QuickSpec+SQRLFixtures.h"
-
-QuickSpecBegin(SQRLShipItRequestSpec)
-
-__block SQRLDirectoryManager *directoryManager;
-__block SQRLShipItRequest *request;
-
-beforeEach(^{
-	directoryManager = SQRLDirectoryManager.currentApplicationManager;
-
-	NSURL *updateURL = [self createTestApplicationUpdate];
-	request = [[SQRLShipItRequest alloc] initWithUpdateBundleURL:updateURL targetBundleURL:self.testApplicationURL bundleIdentifier:nil launchAfterInstallation:NO useUpdateBundleName:NO];
-	expect(request).notTo(beNil());
-
-	expect(request.targetBundleURL).to(equal(self.testApplicationURL));
-	expect(request.updateBundleURL).to(equal(updateURL));
-	expect(request.bundleIdentifier).to(beNil());
-	expect(@(request.launchAfterInstallation)).to(beFalsy());
-});
-
-afterEach(^{
-	NSURL *stateURL = [[directoryManager shipItStateURL] first];
-	expect(stateURL).notTo(beNil());
-
-	[NSFileManager.defaultManager removeItemAtURL:stateURL error:NULL];
-});
-
-it(@"should copy", ^{
-	SQRLShipItRequest *requestCopy = [request copy];
-	expect(requestCopy).to(equal(request));
-	expect(requestCopy).notTo(beIdenticalTo(request));
-});
-
-it(@"should fail to read state when no file exists yet", ^{
-	NSError *error;
-	BOOL success = [[SQRLShipItRequest readUsingURL:directoryManager.shipItStateURL] waitUntilCompleted:&error];
-	expect(@(success)).to(beFalsy());
-	expect(error).notTo(beNil());
-});
-
-it(@"should write and read state to disk", ^{
-	NSError *error;
-	BOOL success = [[request writeUsingURL:directoryManager.shipItStateURL] waitUntilCompleted:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
-
-	SQRLShipItRequest *readRequest = [[SQRLShipItRequest readUsingURL:directoryManager.shipItStateURL] firstOrDefault:nil success:&success error:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
-
-	expect(readRequest).to(equal(request));
-});
-
-it(@"should fail gracefully with archives encoding a different class", ^{
-	NSURL *archiveLocation = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"archive"];
-
-	NSError *error;
-	BOOL write = [[NSKeyedArchiver archivedDataWithRootObject:@"rogue object"] writeToURL:archiveLocation atomically:YES];
-	expect(@(write)).to(beTruthy());
-	expect(error).to(beNil());
-
-	BOOL success = NO;
-	SQRLShipItRequest *request = [[SQRLShipItRequest readUsingURL:[RACSignal return:archiveLocation]] firstOrDefault:nil success:&success error:&error];
-	expect(request).to(beNil());
-	expect(@(success)).to(beFalsy());
-	expect(error.domain).to(equal(SQRLShipItRequestErrorDomain));
-	expect(@(error.code)).to(equal(@(SQRLShipItRequestErrorUnarchiving)));
-});
-
-QuickSpecEnd

SquirrelTests/SQRLShipItStateSpec.m

@@ -0,0 +1,63 @@
+//
+//  SQRLShipItStateSpec.m
+//  Squirrel
+//
+//  Created by Justin Spahr-Summers on 2013-10-09.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLDirectoryManager.h"
+#import "SQRLShipItState.h"
+
+SpecBegin(SQRLShipItState)
+
+__block SQRLDirectoryManager *directoryManager;
+__block SQRLShipItState *state;
+
+beforeEach(^{
+	directoryManager = SQRLDirectoryManager.currentApplicationManager;
+
+	NSURL *updateURL = [self createTestApplicationUpdate];
+	state = [[SQRLShipItState alloc] initWithTargetBundleURL:self.testApplicationURL updateBundleURL:updateURL bundleIdentifier:nil codeSignature:self.testApplicationSignature];
+	expect(state).notTo.beNil();
+
+	expect(state.targetBundleURL).to.equal(self.testApplicationURL);
+	expect(state.updateBundleURL).to.equal(updateURL);
+	expect(state.bundleIdentifier).to.beNil();
+	expect(state.codeSignature).to.equal(self.testApplicationSignature);
+});
+
+afterEach(^{
+	NSURL *stateURL = [[directoryManager shipItStateURL] firstOrDefault:nil success:NULL error:NULL];
+	expect(stateURL).notTo.beNil();
+	
+	[NSFileManager.defaultManager removeItemAtURL:stateURL error:NULL];
+});
+
+it(@"should copy", ^{
+	SQRLShipItState *stateCopy = [state copy];
+	expect(stateCopy).to.equal(state);
+	expect(stateCopy).notTo.beIdenticalTo(state);
+});
+
+it(@"should fail to read state when no file exists yet", ^{
+	NSError *error = nil;
+	BOOL success = [[SQRLShipItState readUsingURL:directoryManager.shipItStateURL] waitUntilCompleted:&error];
+	expect(success).to.beFalsy();
+	expect(error).notTo.beNil();
+});
+
+it(@"should write and read state", ^{
+	NSError *error = nil;
+	BOOL success = [[state writeUsingURL:directoryManager.shipItStateURL] waitUntilCompleted:&error];
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
+
+	SQRLShipItState *readState = [[SQRLShipItState readUsingURL:directoryManager.shipItStateURL] firstOrDefault:nil success:&success error:&error];
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
+
+	expect(readState).to.equal(state);
+});
+
+SpecEnd

SquirrelTests/SQRLTerminationListenerSpec.m

@@ -6,22 +6,15 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
 #import "SQRLTerminationListener.h"
 
-#import "QuickSpec+SQRLFixtures.h"
-
-QuickSpecBegin(SQRLTerminationListenerSpec)
+SpecBegin(SQRLTerminationListener)
 
 __block SQRLTerminationListener *listener;
 
 beforeEach(^{
 	listener = [[SQRLTerminationListener alloc] initWithURL:self.testApplicationURL bundleIdentifier:self.testApplicationBundle.bundleIdentifier];
-	expect(listener).notTo(beNil());
+	expect(listener).notTo.beNil();
 });
 
 it(@"should complete immediately when the app is not running", ^{
@@ -30,12 +23,10 @@ it(@"should complete immediately when the app is not running", ^{
 		completed = YES;
 	}];
 
-	expect(@(completed)).to(beTruthy());
+	expect(completed).to.beTruthy();
 });
 
 it(@"should wait until one instance terminates", ^{
-	SKIP_IF_RUNNING_ON_TRAVIS
-
 	NSRunningApplication *app = [self launchTestApplicationWithEnvironment:nil];
 
 	__block NSRunningApplication *observedApp = nil;
@@ -46,17 +37,15 @@ it(@"should wait until one instance terminates", ^{
 		completed = YES;
 	}];
 
-	expect(observedApp).toEventually(equal(app));
-	expect(@(completed)).to(beFalsy());
+	expect(observedApp).will.equal(app);
+	expect(completed).to.beFalsy();
 
 	[app forceTerminate];
-	expect(@(app.terminated)).toEventually(beTruthy());
-	expect(@(completed)).toEventually(beTruthy());
+	expect(app.terminated).will.beTruthy();
+	expect(completed).will.beTruthy();
 });
 
 it(@"should wait until multiple instances terminate", ^{
-	SKIP_IF_RUNNING_ON_TRAVIS
-
 	NSRunningApplication *app1 = [self launchTestApplicationWithEnvironment:nil];
 	NSRunningApplication *app2 = [self launchTestApplicationWithEnvironment:nil];
 
@@ -65,15 +54,15 @@ it(@"should wait until multiple instances terminate", ^{
 		completed = YES;
 	}];
 
-	expect(@(completed)).to(beFalsy());
+	expect(completed).to.beFalsy();
 
 	[app1 forceTerminate];
-	expect(@(app1.terminated)).toEventually(beTruthy());
-	expect(@(completed)).to(beFalsy());
+	expect(app1.terminated).will.beTruthy();
+	expect(completed).to.beFalsy();
 
 	[app2 forceTerminate];
-	expect(@(app2.terminated)).toEventually(beTruthy());
-	expect(@(completed)).toEventually(beTruthy());
+	expect(app2.terminated).will.beTruthy();
+	expect(completed).will.beTruthy();
 });
 
-QuickSpecEnd
+SpecEnd

SquirrelTests/SQRLTestCase.h

@@ -1,19 +1,11 @@
 //
-//  QuickSpec+SQRLFixtures.h
+//  SQRLTestCase.h
 //  Squirrel
 //
 //  Created by Justin Spahr-Summers on 2013-08-06.
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
-/// See https://github.com/Squirrel/Squirrel.Mac/pull/154#issuecomment-151287744
-#define SKIP_IF_RUNNING_ON_TRAVIS if (self.runningOnTravis) return;
-
 // The short version string for the `testApplicationBundle`.
 extern NSString * const SQRLTestApplicationOriginalShortVersionString;
 
@@ -24,15 +16,10 @@ extern NSString * const SQRLTestApplicationUpdatedShortVersionString;
 // The Info.plist key associated with a bundle's short version string.
 extern NSString * const SQRLBundleShortVersionStringKey;
 
-/// The longer timeout we should use for things that take a long time. This is
-/// especially needed on slower machines (e.g., Travis CI).
-extern const NSTimeInterval SQRLLongTimeout;
-
 @class SQRLCodeSignature;
 @class SQRLDirectoryManager;
-@class SQRLShipItRequest;
 
-@interface QuickSpec (SQRLFixtures)
+@interface SQRLTestCase : SPTSenTestCase
 
 // A URL to a temporary directory tests can use.
 //
@@ -58,12 +45,13 @@ extern const NSTimeInterval SQRLLongTimeout;
 // A code signature with requirements from TestApplication.app.
 @property (nonatomic, strong, readonly) SQRLCodeSignature *testApplicationSignature;
 
+// A serialized `SecRequirementRef` representing the requirements from
+// TestApplication.app.
+@property (nonatomic, copy, readonly) NSData *testApplicationCodeSigningRequirementData;
+
 // A directory manager for finding URLs that apply to ShipIt.
 @property (nonatomic, strong, readonly) SQRLDirectoryManager *shipItDirectoryManager;
 
-/// Are the tests currently being run on Travis?
-@property (nonatomic, readonly, assign, getter = isRunningOnTravis) BOOL runningOnTravis;
-
 // Launches a new copy of TestApplication.app from the `testApplicationBundle`.
 //
 // Invoking this method multiple times will result in multiple running instances
@@ -86,8 +74,8 @@ extern const NSTimeInterval SQRLLongTimeout;
 // deleted at the end of the example.
 - (NSURL *)createTestApplicationUpdate;
 
-// Runs the installer in process or submits ShipIt's launchd job to start it up.
-- (void)installWithRequest:(SQRLShipItRequest *)request remote:(BOOL)remote;
+// Submits ShipIt's launchd job to start it up.
+- (void)launchShipIt;
 
 // Creates a disk image, then mounts it.
 //

SquirrelTests/SQRLTestCase.m

@@ -1,20 +1,16 @@
 //
-//  QuickSpec+SQRLFixtures.m
+//  SQRLTestCase.m
 //  Squirrel
 //
 //  Created by Justin Spahr-Summers on 2013-08-06.
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import "QuickSpec+SQRLFixtures.h"
-
+#import "SQRLTestCase.h"
 #import "SQRLCodeSignature.h"
 #import "SQRLDirectoryManager.h"
-#import "SQRLInstaller.h"
 #import "SQRLShipItLauncher.h"
-#import "SQRLShipItRequest.h"
 #import <ServiceManagement/ServiceManagement.h>
-#import <objc/runtime.h>
 
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Warc-retain-cycles"
@@ -23,8 +19,6 @@ NSString * const SQRLTestApplicationOriginalShortVersionString = @"1.0";
 NSString * const SQRLTestApplicationUpdatedShortVersionString = @"2.1";
 NSString * const SQRLBundleShortVersionStringKey = @"CFBundleShortVersionString";
 
-const NSTimeInterval SQRLLongTimeout = 20;
-
 static void SQRLKillAllTestApplications(void) {
 	// Forcibly kill all copies of the TestApplication that may be running.
 	NSArray *apps = [NSRunningApplication runningApplicationsWithBundleIdentifier:@"com.github.Squirrel.TestApplication"];
@@ -45,98 +39,138 @@ static void SQRLSignalHandler(int sig) {
 	abort();
 }
 
-static NSBundle *SQRLTestBundle(void) {
-	return [NSBundle bundleWithIdentifier:@"com.github.SquirrelTests"];
-}
+@interface SQRLTestCase ()
 
-static NSMutableArray *cleanupBlocks = nil;
+// An array of dispatch_block_t values, for performing cleanup after the current
+// example finishes.
+//
+// This array will be emptied between each example.
+@property (nonatomic, strong, readonly) NSMutableArray *exampleCleanupBlocks;
 
 // The URL to the temporary directory which contains `temporaryDirectoryURL` and
 // all copied test data.
-static NSURL *baseTemporaryDirectoryURL = nil;
+@property (nonatomic, copy, readonly) NSURL *baseTemporaryDirectoryURL;
 
-QuickConfigurationBegin(Fixtures)
+// Returns an _unlaunched_ task that will follow log files at the given paths,
+// then pipe that output through this process.
++ (NSTask *)tailTaskWithPaths:(RACSignal *)paths;
 
-+ (void)configure:(Configuration *)configuration {
+@end
+
+@implementation SQRLTestCase
+
+#pragma mark Properties
+
+@synthesize baseTemporaryDirectoryURL = _baseTemporaryDirectoryURL;
+
+#pragma mark Lifecycle
+
++ (void)load {
 	NSURL *appSupportURL = [NSFileManager.defaultManager URLForDirectory:NSApplicationSupportDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:YES error:NULL];
 	NSAssert(appSupportURL != nil, @"Could not find Application Support folder");
 
 	NSArray *folders = @[
 		@"com.github.Squirrel.TestApplication.ShipIt",
-		@"com.github.Squirrel.SquirrelTests.ShipIt",
+		@"otest.ShipIt",
+		@"otest-x86_64.ShipIt",
 	];
 
-	RACSequence *URLs = [folders.rac_sequence flattenMap:^(NSString *folder) {
-		NSURL *baseURL = [appSupportURL URLByAppendingPathComponent:folder];
-		return @[
-			[baseURL URLByAppendingPathComponent:@"ShipIt_stdout.log"],
-			[baseURL URLByAppendingPathComponent:@"ShipIt_stderr.log"]
-		].rac_sequence;
-	}];
+	RACSignal *logLocations = [[[[folders.rac_signal
+		flattenMap:^(NSString *folder) {
+			return [folder stringsByAppendingPaths:@[
+				@"ShipIt_stdout.log",
+				@"ShipIt_stderr.log",
+			]].rac_signal;
+		}]
+		map:^(NSString *path) {
+			return [appSupportURL URLByAppendingPathComponent:path];
+		}]
+		doNext:^(NSURL *location) {
+			[[NSData data] writeToURL:location atomically:YES];
+		}]
+		map:^(NSURL *location) {
+			return location.path;
+		}];
 
-	[configuration beforeSuite:^{
-		signal(SIGILL, &SQRLSignalHandler);
-		NSSetUncaughtExceptionHandler(&SQRLUncaughtExceptionHandler);
+	NSTask *readShipIt = [self tailTaskWithPaths:logLocations];
+	[readShipIt launch];
 
-		cleanupBlocks = [NSMutableArray array];
+	NSAssert([readShipIt isRunning], @"Could not start task %@", readShipIt);
 
-		for (NSURL *URL in URLs) {
-			[NSFileManager.defaultManager createDirectoryAtURL:URL.URLByDeletingLastPathComponent withIntermediateDirectories:YES attributes:nil error:NULL];
-			if (![[NSData data] writeToURL:URL atomically:YES]) {
-				NSLog(@"Could not touch log file at %@", URL);
-			}
-		}
-	}];
-
-	// We want to run any enqueued cleanup blocks after _and before_ each spec,
-	// in case beforeSuites (for example) use the fixtures.
-	void (^runCleanupBlocks)(void) = ^{
-		// Enumerate backwards, so later resources are cleaned up first.
-		for (dispatch_block_t block in cleanupBlocks.reverseObjectEnumerator) {
-			block();
-		}
-
-		[cleanupBlocks removeAllObjects];
-	};
-
-	[configuration beforeEach:^{
-		runCleanupBlocks();
-	}];
-
-	[configuration afterEach:^{
-		runCleanupBlocks();
-		SQRLKillAllTestApplications();
-	}];
+	atexit_b(^{
+		[readShipIt terminate];
+	});
 }
 
-QuickConfigurationEnd
+- (void)setUp {
+	[super setUp];
 
-@implementation QuickSpec (SQRLFixtures)
+	signal(SIGILL, &SQRLSignalHandler);
+	NSSetUncaughtExceptionHandler(&SQRLUncaughtExceptionHandler);
 
-#pragma mark Lifecycle
+	Expecta.asynchronousTestTimeout = 3;
+}
+
+- (void)SPT_setUp {
+	_exampleCleanupBlocks = [[NSMutableArray alloc] init];
+}
+
+- (void)SPT_tearDown {
+	NSArray *cleanupBlocks = [self.exampleCleanupBlocks copy];
+	_exampleCleanupBlocks = nil;
+
+	// Enumerate backwards, so later resources are cleaned up first.
+	for (dispatch_block_t block in cleanupBlocks.reverseObjectEnumerator) {
+		block();
+	}
+}
+
+- (void)tearDown {
+	[super tearDown];
+
+	SQRLKillAllTestApplications();
+}
 
 - (void)addCleanupBlock:(dispatch_block_t)block {
-	[cleanupBlocks addObject:[block copy]];
+	[self.exampleCleanupBlocks addObject:[block copy]];
+}
+
+#pragma mark Logging
+
++ (NSTask *)tailTaskWithPaths:(RACSignal *)paths {
+	NSPipe *outputPipe = [NSPipe pipe];
+	NSFileHandle *outputHandle = outputPipe.fileHandleForReading;
+
+	outputHandle.readabilityHandler = ^(NSFileHandle *handle) {
+		NSString *output = [[NSString alloc] initWithData:handle.availableData encoding:NSUTF8StringEncoding];
+		NSLog(@"\n%@", output);
+	};
+
+	NSTask *task = [[NSTask alloc] init];
+	task.launchPath = @"/usr/bin/tail";
+	task.standardOutput = outputPipe;
+	task.arguments = [[paths startWith:@"-f"] array];
+	return task;
 }
 
 #pragma mark Temporary Directory
 
 - (NSURL *)baseTemporaryDirectoryURL {
-	if (baseTemporaryDirectoryURL == nil) {
+	if (_baseTemporaryDirectoryURL == nil) {
 		NSURL *globalTemporaryDirectory = [NSURL fileURLWithPath:NSTemporaryDirectory() isDirectory:YES];
-		baseTemporaryDirectoryURL = [[globalTemporaryDirectory URLByAppendingPathComponent:@"com.github.SquirrelTests"] URLByAppendingPathComponent:[NSProcessInfo.processInfo globallyUniqueString]];
-
+		_baseTemporaryDirectoryURL = [[globalTemporaryDirectory URLByAppendingPathComponent:@"com.github.SquirrelTests"] URLByAppendingPathComponent:[NSProcessInfo.processInfo globallyUniqueString]];
+		
 		NSError *error = nil;
-		BOOL success = [NSFileManager.defaultManager createDirectoryAtURL:baseTemporaryDirectoryURL withIntermediateDirectories:YES attributes:nil error:&error];
-		XCTAssertTrue(success, @"Couldn't create temporary directory at %@: %@", baseTemporaryDirectoryURL, error);
+		BOOL success = [NSFileManager.defaultManager createDirectoryAtURL:_baseTemporaryDirectoryURL withIntermediateDirectories:YES attributes:nil error:&error];
+		STAssertTrue(success, @"Couldn't create temporary directory at %@: %@", _baseTemporaryDirectoryURL, error);
 
 		[self addCleanupBlock:^{
-			[NSFileManager.defaultManager removeItemAtURL:baseTemporaryDirectoryURL error:NULL];
-			baseTemporaryDirectoryURL = nil;
+			[NSFileManager.defaultManager removeItemAtURL:_baseTemporaryDirectoryURL error:NULL];
+			_baseTemporaryDirectoryURL = nil;
 		}];
 	}
 
-	return baseTemporaryDirectoryURL;
+	return _baseTemporaryDirectoryURL;
 }
 
 - (NSURL *)temporaryDirectoryURL {
@@ -144,7 +178,7 @@ QuickConfigurationEnd
 
 	NSError *error = nil;
 	BOOL success = [NSFileManager.defaultManager createDirectoryAtURL:temporaryDirectoryURL withIntermediateDirectories:YES attributes:nil error:&error];
-	XCTAssertTrue(success, @"Couldn't create temporary directory at %@: %@", temporaryDirectoryURL, error);
+	STAssertTrue(success, @"Couldn't create temporary directory at %@: %@", temporaryDirectoryURL, error);
 
 	return temporaryDirectoryURL;
 }
@@ -154,15 +188,24 @@ QuickConfigurationEnd
 - (NSURL *)testApplicationURL {
 	NSURL *fixtureURL = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"TestApplication.app" isDirectory:YES];
 	if (![NSFileManager.defaultManager fileExistsAtPath:fixtureURL.path]) {
-		NSURL *bundleURL = [SQRLTestBundle() URLForResource:@"TestApplication" withExtension:@"app"];
-		XCTAssertNotNil(bundleURL, @"Couldn't find TestApplication.app in test bundle");
+		NSURL *bundleURL = [[NSBundle bundleForClass:self.class] URLForResource:@"TestApplication" withExtension:@"app"];
+		STAssertNotNil(bundleURL, @"Couldn't find TestApplication.app in test bundle");
 
 		NSError *error = nil;
 		BOOL success = [NSFileManager.defaultManager copyItemAtURL:bundleURL toURL:fixtureURL error:&error];
-		XCTAssertTrue(success, @"Couldn't copy %@ to %@: %@", bundleURL, fixtureURL, error);
+		STAssertTrue(success, @"Couldn't copy %@ to %@: %@", bundleURL, fixtureURL, error);
 
 		NSURL *testAppLog = [fixtureURL.URLByDeletingLastPathComponent URLByAppendingPathComponent:@"TestApplication.log"];
 		[[NSData data] writeToURL:testAppLog atomically:YES];
+
+		NSTask *readTestApp = [self.class tailTaskWithPaths:[RACSignal return:testAppLog.path]];
+		[readTestApp launch];
+
+		STAssertTrue([readTestApp isRunning], @"Could not start task %@ to read %@", readTestApp, testAppLog);
+
+		[self addCleanupBlock:^{
+			[readTestApp terminate];
+		}];
 	}
 
 	return fixtureURL;
@@ -171,8 +214,8 @@ QuickConfigurationEnd
 - (NSBundle *)testApplicationBundle {
 	NSURL *fixtureURL = self.testApplicationURL;
 	NSBundle *bundle = [NSBundle bundleWithURL:fixtureURL];
-	XCTAssertNotNil(bundle, @"Couldn't open bundle at %@", fixtureURL);
-
+	STAssertNotNil(bundle, @"Couldn't open bundle at %@", fixtureURL);
+	
 	return bundle;
 }
 
@@ -191,7 +234,7 @@ QuickConfigurationEnd
 
 	NSError *error = nil;
 	NSRunningApplication *app = [NSWorkspace.sharedWorkspace launchApplicationAtURL:self.testApplicationURL options:NSWorkspaceLaunchWithoutAddingToRecents | NSWorkspaceLaunchWithoutActivation | NSWorkspaceLaunchNewInstance | NSWorkspaceLaunchAndHide configuration:configuration error:&error];
-	XCTAssertNotNil(app, @"Could not launch app at %@: %@", self.testApplicationURL, error);
+	STAssertNotNil(app, @"Could not launch app at %@: %@", self.testApplicationURL, error);
 
 	[self addCleanupBlock:^{
 		if (!app.terminated) {
@@ -211,12 +254,12 @@ QuickConfigurationEnd
 }
 
 - (NSURL *)createTestApplicationUpdate {
-	NSURL *originalURL = [SQRLTestBundle() URLForResource:@"TestApplication 2.1" withExtension:@"app"];
-	XCTAssertNotNil(originalURL, @"Couldn't find TestApplication update in test bundle");
+	NSURL *originalURL = [[NSBundle bundleForClass:self.class] URLForResource:@"TestApplication 2.1" withExtension:@"app"];
+	STAssertNotNil(originalURL, @"Couldn't find TestApplication update in test bundle");
 
 	NSError *error = nil;
 	NSURL *updateParentURL = [NSFileManager.defaultManager URLForDirectory:NSItemReplacementDirectory inDomain:NSUserDomainMask appropriateForURL:self.baseTemporaryDirectoryURL create:YES error:&error];
-	XCTAssertNotNil(updateParentURL, @"Could not create temporary directory for updating: %@", error);
+	STAssertNotNil(updateParentURL, @"Could not create temporary directory for updating: %@", error);
 
 	[self addCleanupBlock:^{
 		[NSFileManager.defaultManager removeItemAtURL:updateParentURL error:NULL];
@@ -224,18 +267,18 @@ QuickConfigurationEnd
 
 	NSURL *updateURL = [updateParentURL URLByAppendingPathComponent:originalURL.lastPathComponent isDirectory:YES];
 	BOOL success = [NSFileManager.defaultManager copyItemAtURL:originalURL toURL:updateURL error:&error];
-	XCTAssertTrue(success, @"Couldn't copy %@ to %@: %@", originalURL, updateURL, error);
+	STAssertTrue(success, @"Couldn't copy %@ to %@: %@", originalURL, updateURL, error);
 
 	return updateURL;
 }
 
 - (id)performWithTestApplicationRequirement:(id (^)(SecRequirementRef requirement))block {
-	NSURL *bundleURL = [SQRLTestBundle() URLForResource:@"TestApplication" withExtension:@"app"];
-	XCTAssertNotNil(bundleURL, @"Couldn't find TestApplication.app in test bundle");
+	NSURL *bundleURL = [[NSBundle bundleForClass:self.class] URLForResource:@"TestApplication" withExtension:@"app"];
+	STAssertNotNil(bundleURL, @"Couldn't find TestApplication.app in test bundle");
 
 	SecStaticCodeRef staticCode = NULL;
 	OSStatus status = SecStaticCodeCreateWithPath((__bridge CFURLRef)bundleURL, kSecCSDefaultFlags, &staticCode);
-	XCTAssertTrue(status == noErr, @"Error creating static code object for %@", bundleURL);
+	STAssertTrue(status == noErr, @"Error creating static code object for %@", bundleURL);
 
 	@onExit {
 		if (staticCode != NULL) CFRelease(staticCode);
@@ -243,7 +286,7 @@ QuickConfigurationEnd
 
 	SecRequirementRef requirement = NULL;
 	status = SecCodeCopyDesignatedRequirement(staticCode, kSecCSDefaultFlags, &requirement);
-	XCTAssertTrue(status == noErr, @"Error getting designated requirement of %@", staticCode);
+	STAssertTrue(status == noErr, @"Error getting designated requirement of %@", staticCode);
 
 	@onExit {
 		if (requirement != NULL) CFRelease(requirement);
@@ -253,57 +296,48 @@ QuickConfigurationEnd
 }
 
 - (SQRLCodeSignature *)testApplicationSignature {
-	NSURL *bundleURL = [SQRLTestBundle() URLForResource:@"TestApplication" withExtension:@"app"];
-	XCTAssertNotNil(bundleURL, @"Couldn't find TestApplication.app in test bundle");
+	return [self performWithTestApplicationRequirement:^(SecRequirementRef requirement) {
+		return [[SQRLCodeSignature alloc] initWithRequirement:requirement];
+	}];
+}
 
-	NSError *error = nil;
-	SQRLCodeSignature *signature = [SQRLCodeSignature signatureWithBundle:bundleURL error:&error];
-	XCTAssertNotNil(signature, @"Error getting signature for bundle at %@: %@", bundleURL, error);
+- (NSData *)testApplicationCodeSigningRequirementData {
+	return [self performWithTestApplicationRequirement:^(SecRequirementRef requirement) {
+		CFDataRef data = NULL;
+		OSStatus status = SecRequirementCopyData(requirement, kSecCSDefaultFlags, &data);
+		STAssertTrue(status == noErr, @"Error copying data for requirement %@", requirement);
 
-	return signature;
+		return CFBridgingRelease(data);
+	}];
 }
 
 - (SQRLDirectoryManager *)shipItDirectoryManager {
 	NSString *identifier = SQRLShipItLauncher.shipItJobLabel;
 	SQRLDirectoryManager *manager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:identifier];
-	XCTAssertNotNil(manager, @"Could not create directory manager for %@", identifier);
+	STAssertNotNil(manager, @"Could not create directory manager for %@", identifier);
 
 	return manager;
 }
 
-- (void)installWithRequest:(SQRLShipItRequest *)request remote:(BOOL)remote {
-	if (remote) {
-		expect(@([[request writeUsingURL:self.shipItDirectoryManager.shipItStateURL] waitUntilCompleted:NULL])).to(beTruthy());
+- (void)launchShipIt {
+	NSError *error = nil;
+	STAssertTrue([[SQRLShipItLauncher launchPrivileged:NO] waitUntilCompleted:&error], @"Could not launch ShipIt: %@", error);
 
-		__block NSError *error = nil;
-		expect(@([[SQRLShipItLauncher launchPrivileged:NO] waitUntilCompleted:&error])).to(beTruthy());
-		expect(error).to(beNil());
+	[self addCleanupBlock:^{
+		// Remove ShipIt's launchd job so it doesn't relaunch itself.
+		SMJobRemove(kSMDomainUserLaunchd, (__bridge CFStringRef)SQRLShipItLauncher.shipItJobLabel, NULL, true, NULL);
 
-		[self addCleanupBlock:^{
-			// Remove ShipIt's launchd job so it doesn't relaunch itself.
-			SMJobRemove(kSMDomainUserLaunchd, (__bridge CFStringRef)SQRLShipItLauncher.shipItJobLabel, NULL, true, NULL);
-
-			NSError *lookupError;
-			NSURL *stateURL = [[self.shipItDirectoryManager shipItStateURL] firstOrDefault:nil success:NULL error:&lookupError];
-			expect(stateURL).notTo(beNil());
-			expect(lookupError).to(beNil());
-
-			[NSFileManager.defaultManager removeItemAtURL:stateURL error:NULL];
-		}];
-	} else {
-		SQRLInstaller *installer = [[SQRLInstaller alloc] initWithApplicationIdentifier:self.shipItDirectoryManager.applicationIdentifier];
-		expect(installer).notTo(beNil());
-
-		NSError *installedError = nil;
-		BOOL installed = [[installer.installUpdateCommand execute:request] asynchronouslyWaitUntilCompleted:&installedError];
-		expect(@(installed)).to(beTruthy());
-		expect(installedError).to(beNil());
-	}
+		NSError *lookupError = nil;
+		NSURL *stateURL = [[self.shipItDirectoryManager shipItStateURL] firstOrDefault:nil success:NULL error:&lookupError];
+		STAssertNotNil(stateURL, @"Could not find state URL from %@: %@", self.shipItDirectoryManager, lookupError);
+		
+		[NSFileManager.defaultManager removeItemAtURL:stateURL error:NULL];
+	}];
 }
 
 - (NSURL *)createAndMountDiskImageNamed:(NSString *)name fromDirectory:(NSURL *)directoryURL {
 	NSURL *destinationURL = [self.baseTemporaryDirectoryURL URLByAppendingPathComponent:name];
-	XCTAssertNotNil(destinationURL, @"Could not create disk image URL for %@", directoryURL);
+	STAssertNotNil(destinationURL, @"Could not create disk image URL for %@", directoryURL);
 
 	NSString *createInvocation;
 	if (directoryURL == nil) {
@@ -312,24 +346,20 @@ QuickConfigurationEnd
 		createInvocation = [NSString stringWithFormat:@"hdiutil create '%@' -fs 'HFS+' -volname '%@' -format UDSP -size 10m -srcfolder '%@' -quiet", destinationURL.path, name, directoryURL.path];
 	}
 
-	expect(@(system(createInvocation.UTF8String))).to(equal(@0));
+	expect(system(createInvocation.UTF8String)).to.equal(0);
 
 	NSString *mountInvocation = [NSString stringWithFormat:@"hdiutil attach '%@.sparseimage' -noverify -noautofsck -readwrite -quiet", destinationURL.path];
-	expect(@(system(mountInvocation.UTF8String))).to(equal(@0));
+	expect(system(mountInvocation.UTF8String)).to.equal(0);
 
 	NSString *path = [NSString stringWithFormat:@"/Volumes/%@", name];
 	[self addCleanupBlock:^{
 		NSString *detachInvocation = [NSString stringWithFormat:@"hdiutil detach '%@' -force -quiet", path];
-		expect(@(system(detachInvocation.UTF8String))).to(equal(@0));
+		expect(system(detachInvocation.UTF8String)).to.equal(0);
 	}];
 
 	return [NSURL fileURLWithPath:path isDirectory:YES];
 }
 
-- (BOOL)isRunningOnTravis {
-	return NSProcessInfo.processInfo.environment[@"TRAVIS"] != nil;
-}
-
 @end
 
 #pragma clang diagnostic pop

SquirrelTests/SQRLURLConnectionSpec.m

@@ -0,0 +1,311 @@
+//
+//  SQRLURLConnectionSpec.m
+//  Squirrel
+//
+//  Created by Keith Duncan on 27/09/2013.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#import "SQRLURLConnection.h"
+#import "SQRLDownloadManager.h"
+#import "SQRLResumableDownload.h"
+#import <ReactiveCocoa/EXTScope.h>
+#import "NSError+SQRLVerbosityExtensions.h"
+#import "SQRLHTTPServer.h"
+
+SpecBegin(SQRLURLConnection);
+
+__block SQRLDownloadManager *downloadManager;
+
+beforeAll(^{
+	downloadManager = SQRLDownloadManager.defaultDownloadManager;
+
+	NSError *removeError = nil;
+	BOOL remove = [[downloadManager
+		removeAllResumableDownloads]
+		waitUntilCompleted:&removeError];
+	expect(remove).to.beTruthy();
+	expect(removeError).to.beNil();
+});
+
+beforeEach(^{
+	Expecta.asynchronousTestTimeout = 60.;
+});
+
+afterAll(^{
+	Expecta.asynchronousTestTimeout = 1.;
+});
+
+describe(@"file scheme URLs", ^{
+	NSURL *fileLocation = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"test"];
+	NSData *testContents = [@"test" dataUsingEncoding:NSUTF8StringEncoding];
+
+	NSError *error;
+	BOOL write = [testContents writeToURL:fileLocation options:0 error:&error];
+	expect(write).to.beTruthy();
+	expect(error).to.beNil();
+
+	NSURLRequest *request = [NSURLRequest requestWithURL:fileLocation];
+
+	__block SQRLURLConnection *connection;
+
+	beforeEach(^{
+		connection = [[SQRLURLConnection alloc] initWithRequest:request];
+	});
+
+	void (^testBodyEqualTestContents)(NSData *) = ^ (NSData *body) {
+		expect(body.length).to.equal(testContents.length);
+		expect(body).to.equal(testContents);
+	};
+
+	it(@"should retrieve file:// scheme URLs", ^{
+		NSError *error;
+		RACTuple *result = [[connection retrieve] firstOrDefault:nil success:NULL error:&error];
+		expect(result).notTo.beNil();
+		expect(error).to.beNil();
+
+		testBodyEqualTestContents(result[1]);
+	});
+
+	it(@"should download file:// scheme URLs", ^{
+		NSError *error;
+		RACTuple *result = [[connection download:downloadManager] firstOrDefault:nil success:NULL error:&error];
+		expect(result).notTo.beNil();
+		expect(error).to.beNil();
+
+		NSURL *location = result[1];
+
+		NSData *body = [NSData dataWithContentsOfURL:location options:0 error:&error];
+		expect(error).to.beNil();
+		testBodyEqualTestContents(body);
+	});
+});
+
+static NSData * (^stringTimes)(NSString *, NSUInteger) = ^ (NSString *string, NSUInteger times) {
+	NSData *stringData = [string dataUsingEncoding:NSUTF8StringEncoding];
+	NSMutableData *data = [NSMutableData dataWithCapacity:(stringData.length + 2) * times];
+	for (NSUInteger idx = 0; idx < times; idx++) {
+		[data appendData:stringData];
+		[data appendData:[NSData dataWithBytes:"\r\n" length:2]];
+	}
+	return data;
+};
+
+static SQRLHTTPServer * (^newHttpServer)(SQRLTestCase *) = ^ (SQRLTestCase *self) {
+	SQRLHTTPServer *server = [[SQRLHTTPServer alloc] init];
+
+	[self addCleanupBlock:^{
+		[server invalidate];
+	}];
+
+	return server;
+};
+
+it(@"should resume a download", ^{
+	// Start server
+
+	SQRLHTTPServer *server = newHttpServer(self);
+
+	NSError *error = nil;
+	NSURL *baseURL = [server start:&error];
+	expect(baseURL).notTo.beNil();
+	expect(error).to.beNil();
+
+	error = nil;
+
+
+	// Prepare half response
+
+	NSData *firstHalf = stringTimes(@"the quick brown fox", 100);
+	NSData *secondHalf = stringTimes(@"jumped over the lazy doge", 100);
+
+	NSString *ETag = NSProcessInfo.processInfo.globallyUniqueString;
+
+	CFHTTPMessageRef serverResponse = (__bridge CFHTTPMessageRef)CFBridgingRelease(CFHTTPMessageCreateResponse(kCFAllocatorDefault, 200, NULL, kCFHTTPVersion1_1));
+	NSDictionary *responseHeaders = @{
+		@"Content-Length": [@(firstHalf.length + secondHalf.length) stringValue],
+		@"ETag": ETag,
+	};
+	[responseHeaders enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) {
+		CFHTTPMessageSetHeaderFieldValue(serverResponse, (__bridge CFStringRef)key, (__bridge CFStringRef)obj);
+	}];
+	CFHTTPMessageSetBody(serverResponse, (__bridge CFDataRef)firstHalf);
+
+	server.responseBlock = ^ (CFHTTPMessageRef request) {
+		NSString *ifRange = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("If-Range")));
+		expect(ifRange).to.beNil();
+
+		NSString *range = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("Range")));
+		expect(range).to.beNil();
+
+		return serverResponse;
+	};
+
+
+	// Issue first request
+
+	NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:baseURL];
+	request.timeoutInterval = 1.;
+	SQRLURLConnection *connection = [[SQRLURLConnection alloc] initWithRequest:request];
+	RACTuple *result = [[connection download:downloadManager] firstOrDefault:nil success:NULL error:&error];
+	expect(result).to.beNil();
+	expect(error).notTo.beNil();
+
+	error = nil;
+
+	SQRLResumableDownload *download = [[downloadManager downloadForRequest:request] firstOrDefault:nil success:NULL error:&error];
+	expect(download).notTo.beNil();
+	expect(error).to.beNil();
+
+	NSData *downloadedData = [NSData dataWithContentsOfURL:download.fileURL options:0 error:&error];
+	expect(downloadedData.length).to.equal(firstHalf.length);
+	expect(downloadedData).to.equal(firstHalf);
+	expect(error).to.beNil();
+
+
+	// Prepare remainder response
+
+	serverResponse = CFHTTPMessageCreateResponse(kCFAllocatorDefault, 206, NULL, kCFHTTPVersion1_1);
+	responseHeaders = @{
+		@"Content-Length": [@(secondHalf.length) stringValue],
+		@"Range": [NSString stringWithFormat:@"%lu-%lu", firstHalf.length, secondHalf.length - 1],
+		@"ETag": ETag,
+	};
+	[responseHeaders enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) {
+		CFHTTPMessageSetHeaderFieldValue(serverResponse, (__bridge CFStringRef)key, (__bridge CFStringRef)obj);
+	}];
+	CFHTTPMessageSetBody(serverResponse, (__bridge CFDataRef)secondHalf);
+
+	server.responseBlock = ^ (CFHTTPMessageRef request) {
+		NSString *ifRange = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("If-Range")));
+		expect(ifRange).to.equal(ETag);
+
+		NSString *range = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("Range")));
+		expect(range).to.equal(([NSString stringWithFormat:@"%lu-", firstHalf.length]));
+
+		return serverResponse;
+	};
+
+
+	// Issue second request
+
+	connection = [[SQRLURLConnection alloc] initWithRequest:request];
+	result = [[connection download:downloadManager] firstOrDefault:nil success:NULL error:&error];
+	expect(result).notTo.beNil();
+	expect(error).to.beNil();
+
+	NSURL *location = result[1];
+
+	NSMutableData *fullBody = [firstHalf mutableCopy];
+	[fullBody appendData:secondHalf];
+
+	downloadedData = [NSData dataWithContentsOfURL:location options:0 error:&error];
+	expect(downloadedData.length).to.equal(fullBody.length);
+	expect(downloadedData).to.equal(fullBody);
+	expect(error).to.beNil();
+});
+
+it(@"should not resume downloads for a response with a different ETag", ^{
+	// Start server
+
+	SQRLHTTPServer *server = newHttpServer(self);
+
+	NSError *error = nil;
+	NSURL *baseURL = [server start:&error];
+	expect(baseURL).notTo.beNil();
+	expect(error).to.beNil();
+
+	error = nil;
+
+
+	// Prepare first response
+
+	NSData *firstBody = stringTimes(@"the quick brown fox", 100);
+	NSString *firstETag = NSProcessInfo.processInfo.globallyUniqueString;
+
+	CFHTTPMessageRef serverResponse = (__bridge CFHTTPMessageRef)CFBridgingRelease(CFHTTPMessageCreateResponse(kCFAllocatorDefault, 200, NULL, kCFHTTPVersion1_1));
+	NSDictionary *responseHeaders = @{
+		// Claim the response to be longer so that the connection will timeout
+		// waiting for the extra bytes
+		@"Content-Length": [@(firstBody.length + 100) stringValue],
+		@"ETag": firstETag,
+	};
+	[responseHeaders enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) {
+		CFHTTPMessageSetHeaderFieldValue(serverResponse, (__bridge CFStringRef)key, (__bridge CFStringRef)obj);
+	}];
+	CFHTTPMessageSetBody(serverResponse, (__bridge CFDataRef)firstBody);
+
+	server.responseBlock = ^ (CFHTTPMessageRef request) {
+		NSString *ifRange = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("If-Range")));
+		expect(ifRange).to.beNil();
+
+		NSString *range = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("Range")));
+		expect(range).to.beNil();
+
+		return serverResponse;
+	};
+
+
+	// Issue first request
+
+	NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:baseURL];
+	request.timeoutInterval = 1.;
+	SQRLURLConnection *connection = [[SQRLURLConnection alloc] initWithRequest:request];
+	RACTuple *result = [[connection download:downloadManager] firstOrDefault:nil success:NULL error:&error];
+	expect(result).to.beNil();
+	expect(error).notTo.beNil();
+
+	error = nil;
+
+	SQRLResumableDownload *download = [[downloadManager downloadForRequest:request] firstOrDefault:nil success:NULL error:&error];
+	expect(download).notTo.beNil();
+	expect(error).to.beNil();
+
+	NSData *downloadedData = [NSData dataWithContentsOfURL:download.fileURL options:0 error:&error];
+	expect(downloadedData.length).to.equal(firstBody.length);
+	expect(downloadedData).to.equal(firstBody);
+	expect(error).to.beNil();
+
+
+	// Prepare second response
+
+	NSData *secondBody = stringTimes(@"jumps over the lazy doge", 100);
+	NSString *secondETag = NSProcessInfo.processInfo.globallyUniqueString;
+
+	serverResponse = (__bridge CFHTTPMessageRef)CFBridgingRelease(CFHTTPMessageCreateResponse(kCFAllocatorDefault, 200, NULL, kCFHTTPVersion1_1));
+	responseHeaders = @{
+		@"Content-Length": [@(secondBody.length) stringValue],
+		@"ETag": secondETag,
+	};
+	[responseHeaders enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) {
+		CFHTTPMessageSetHeaderFieldValue(serverResponse, (__bridge CFStringRef)key, (__bridge CFStringRef)obj);
+	}];
+	CFHTTPMessageSetBody(serverResponse, (__bridge CFDataRef)secondBody);
+
+	server.responseBlock = ^ (CFHTTPMessageRef request) {
+		NSString *ifRange = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("If-Range")));
+		expect(ifRange).to.equal(firstETag);
+
+		NSString *range = CFBridgingRelease(CFHTTPMessageCopyHeaderFieldValue(request, CFSTR("Range")));
+		expect(range).to.equal(([NSString stringWithFormat:@"%lu-", firstBody.length]));
+
+		return serverResponse;
+	};
+
+
+	// Issue second request
+
+	connection = [[SQRLURLConnection alloc] initWithRequest:request];
+	result = [[connection download:downloadManager] firstOrDefault:nil success:NULL error:&error];
+	expect(result).notTo.beNil();
+	expect(error).to.beNil();
+
+	NSURL *location = result[1];
+
+	downloadedData = [NSData dataWithContentsOfURL:location options:0 error:&error];
+	expect(downloadedData.length).to.equal(secondBody.length);
+	expect(downloadedData).to.equal(secondBody);
+	expect(error).to.beNil();
+});
+
+SpecEnd

SquirrelTests/SQRLUpdateSpec.m

@@ -6,27 +6,22 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
-QuickSpecBegin(SQRLUpdateSpec)
+SpecBegin(SQRLUpdate)
 
 it(@"should return nil when initialised without a url", ^{
 	NSError *error = nil;
 	SQRLUpdate *update = [[SQRLUpdate alloc] initWithDictionary:@{} error:&error];
-	expect(update).to(beNil());
-	expect(error.domain).to(equal(NSCocoaErrorDomain));
-	expect(@(error.code)).to(equal(@(NSKeyValueValidationError)));
+	expect(update).to.beNil();
+	expect(error.domain).to.equal(NSCocoaErrorDomain);
+	expect(error.code).to.equal(NSKeyValueValidationError);
 });
 
 it(@"should return nil when initialised with a url not in URL syntax", ^{
 	NSError *error = nil;
 	SQRLUpdate *update = [[SQRLUpdate alloc] initWithDictionary:@{ @"updateURL": [NSURL URLWithString:@"test"] } error:&error];
-	expect(update).to(beNil());
-	expect(error.domain).to(equal(NSCocoaErrorDomain));
-	expect(@(error.code)).to(equal(@(NSKeyValueValidationError)));
+	expect(update).to.beNil();
+	expect(error.domain).to.equal(NSCocoaErrorDomain);
+	expect(error.code).to.equal(NSKeyValueValidationError);
 });
 
 it(@"should validate release name and notes", ^{
@@ -37,20 +32,24 @@ it(@"should validate release name and notes", ^{
 		@"releaseNotes": [[NSObject alloc] init]
 	} error:NULL];
 
-	expect(update).notTo(beNil());
-	expect(update.updateURL).to(equal(updateURL));
-	expect(update.releaseName).to(beNil());
-	expect(update.releaseNotes).to(beNil());
+	expect(update).notTo.beNil();
+	expect(update.updateURL).to.equal(updateURL);
+	expect(update.releaseName).to.beNil();
+	expect(update.releaseNotes).to.beNil();
 });
 
 it(@"should parse Central style dates", ^{
-	SQRLUpdate *update = [MTLJSONAdapter modelOfClass:SQRLUpdate.class fromJSONDictionary:@{ @"url": @"http://example.com/update", @"pub_date": @"Tue Sep 17 10:24:27 -0700 2013" } error:NULL];
-	expect(update.releaseDate).to(equal([NSDate dateWithTimeIntervalSince1970:1379438667]));
+	NSError *error = nil;
+	SQRLUpdate *update = [MTLJSONAdapter modelOfClass:SQRLUpdate.class fromJSONDictionary:@{ @"url": @"http://example.com/update", @"pub_date": @"Tue Sep 17 10:24:27 -0700 2013" } error:&error];
+	expect(update.releaseDate).notTo.beNil();
+	expect(error).to.beNil();
 });
 
 it(@"should parse ISO 8601 dates", ^{
-	SQRLUpdate *update = [MTLJSONAdapter modelOfClass:SQRLUpdate.class fromJSONDictionary:@{ @"url": @"http://example.com/update", @"pub_date": @"2013-09-18T13:17:07+01:00" } error:NULL];
-	expect(update.releaseDate).to(equal([NSDate dateWithTimeIntervalSince1970:1379506627]));
+	NSError *error = nil;
+	SQRLUpdate *update = [MTLJSONAdapter modelOfClass:SQRLUpdate.class fromJSONDictionary:@{ @"url": @"http://example.com/update", @"pub_date": @"2013-09-18T13:17:07+01:00" } error:&error];
+	expect(update.releaseDate).notTo.beNil();
+	expect(error).to.beNil();
 });
 
-QuickSpecEnd
+SpecEnd

SquirrelTests/SQRLUpdaterSpec.m

@@ -6,44 +6,38 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
-#import "SQRLDirectoryManager.h"
-#import "SQRLZipArchiver.h"
-
-#import "OHHTTPStubs/OHHTTPStubs.h"
-#import "QuickSpec+SQRLFixtures.h"
 #import "SQRLTestUpdate.h"
-#import "TestAppConstants.h"
+#import "SQRLZipArchiver.h"
+#import "OHHTTPStubs/OHHTTPStubs.h"
+#import "SQRLDirectoryManager.h"
+#import "SQRLURLConnection.h"
+#import "SQRLDownloadManager.h"
 
-QuickSpecBegin(SQRLUpdaterSpec)
+SpecBegin(SQRLUpdater)
 
 __block NSURL *JSONURL;
 
 void (^writeUpdate)(SQRLUpdate *) = ^(SQRLUpdate *update) {
 	NSDictionary *updateInfo = [MTLJSONAdapter JSONDictionaryFromModel:update];
-	expect(updateInfo).notTo(beNil());
+	expect(updateInfo).notTo.beNil();
 
 	NSError *error = nil;
 	NSData *JSON = [NSJSONSerialization dataWithJSONObject:updateInfo options:NSJSONWritingPrettyPrinted error:&error];
-	expect(JSON).notTo(beNil());
-	expect(error).to(beNil());
+	expect(JSON).notTo.beNil();
+	expect(error).to.beNil();
 
 	BOOL success = [JSON writeToURL:JSONURL options:NSDataWritingAtomic error:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
 };
 
 NSURL * (^zipUpdate)(NSURL *) = ^(NSURL *updateURL) {
 	NSURL *zipFolderURL = [NSFileManager.defaultManager URLForDirectory:NSItemReplacementDirectory inDomain:NSUserDomainMask appropriateForURL:self.temporaryDirectoryURL create:YES error:NULL];
-	expect(zipFolderURL).notTo(beNil());
+	expect(zipFolderURL).notTo.beNil();
 
 	NSURL *zippedUpdateURL = [[zipFolderURL URLByAppendingPathComponent:updateURL.lastPathComponent] URLByAppendingPathExtension:@"zip"];
 	BOOL success = [[SQRLZipArchiver createZipArchiveAtURL:zippedUpdateURL fromDirectoryAtURL:updateURL] asynchronouslyWaitUntilCompleted:NULL];
-	expect(@(success)).to(beTruthy());
+	expect(success).to.beTruthy();
 
 	return zippedUpdateURL;
 };
@@ -59,150 +53,96 @@ beforeEach(^{
 	JSONURL = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"update.json"];
 });
 
-describe(@"updating", ^{
-	__block NSURL *updateURL;
+it(@"should use the application's bundled version of Squirrel and update in-place", ^{
+	NSURL *updateURL = [self createTestApplicationUpdate];
 
-	beforeEach(^{
-		updateURL = [self createTestApplicationUpdate];
-	});
+	NSError *error = nil;
+	SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
+		@"updateURL": zipUpdate(updateURL),
+		@"final": @YES
+	} error:&error];
+	expect(update).notTo.beNil();
+	expect(error).to.beNil();
 
-	it(@"should use the application's bundled version of Squirrel and update in-place", ^{
-		SKIP_IF_RUNNING_ON_TRAVIS
+	writeUpdate(update);
 
-		NSError *error = nil;
-		SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
-			@"updateURL": zipUpdate(updateURL),
-			@"final": @YES
-		} error:&error];
-		expect(update).notTo(beNil());
-		expect(error).to(beNil());
+	NSRunningApplication *app = launchWithEnvironment(nil);
+	expect(app.terminated).will.beTruthy();
+	expect(self.testApplicationBundleVersion).will.equal(SQRLTestApplicationUpdatedShortVersionString);
+});
 
-		writeUpdate(update);
+it(@"should not install a corrupt update", ^{
+	NSURL *updateURL = [self createTestApplicationUpdate];
+	NSURL *codeSignatureURL = [updateURL URLByAppendingPathComponent:@"Contents/_CodeSignature"];
+	expect([NSFileManager.defaultManager removeItemAtURL:codeSignatureURL error:NULL]).to.beTruthy();
 
-		NSRunningApplication *app = launchWithEnvironment(nil);
-		expect(@(app.terminated)).withTimeout(SQRLLongTimeout).toEventually(beTruthy());
-		expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
-	});
+	SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
+		@"updateURL": zipUpdate(updateURL),
+		@"final": @YES
+	} error:NULL];
 
-	it(@"should not install a corrupt update", ^{
-		SKIP_IF_RUNNING_ON_TRAVIS
+	writeUpdate(update);
 
-		NSURL *codeSignatureURL = [updateURL URLByAppendingPathComponent:@"Contents/_CodeSignature"];
-		expect(@([NSFileManager.defaultManager removeItemAtURL:codeSignatureURL error:NULL])).to(beTruthy());
+	NSRunningApplication *app = launchWithEnvironment(nil);
+	expect(app.terminated).will.beTruthy();
 
-		SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
-			@"updateURL": zipUpdate(updateURL),
-			@"final": @YES
-		} error:NULL];
+	// Give the update some time to finish installing.
+	[NSThread sleepForTimeInterval:0.2];
+	expect(self.testApplicationBundleVersion).to.equal(SQRLTestApplicationOriginalShortVersionString);
+});
 
-		writeUpdate(update);
+it(@"should update to the most recently enqueued job", ^{
+	SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
+		@"updateURL": zipUpdate(self.testApplicationURL)
+	} error:NULL];
 
-		NSRunningApplication *app = launchWithEnvironment(nil);
-		expect(@(app.terminated)).withTimeout(SQRLLongTimeout).toEventually(beTruthy());
+	writeUpdate(update);
 
-		// Give the update some time to finish installing.
-		[NSThread sleepForTimeInterval:0.2];
-		expect(self.testApplicationBundleVersion).to(equal(SQRLTestApplicationOriginalShortVersionString));
-	});
+	NSRunningApplication *app = launchWithEnvironment(nil);
 
-	it(@"should update to the most recently enqueued job", ^{
-		SKIP_IF_RUNNING_ON_TRAVIS
+	// Now that Test Application is launched, it's going to keep checking the
+	// JSON URL until it has the proper release name. So we'll wait a short bit,
+	// and then add the correct name in.
+	//
+	// This exercises ShipIt's ability to discard previous commands and
+	// install an even newer update.
+	[NSThread sleepForTimeInterval:0.3];
 
-		SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
-			@"updateURL": zipUpdate(self.testApplicationURL)
-		} error:NULL];
+	NSURL *updateURL = [self createTestApplicationUpdate];
+	update = [SQRLTestUpdate modelWithDictionary:@{
+		@"updateURL": zipUpdate(updateURL),
+		@"final": @YES
+	} error:NULL];
 
-		writeUpdate(update);
+	writeUpdate(update);
 
-		NSRunningApplication *app = launchWithEnvironment(nil);
+	expect(app.terminated).will.beTruthy();
+	expect(self.testApplicationBundleVersion).will.equal(SQRLTestApplicationUpdatedShortVersionString);
+});
 
-		// Now that Test Application is launched, it's going to keep checking the
-		// JSON URL until it has the proper release name. So we'll wait a short bit,
-		// and then add the correct name in.
-		//
-		// This exercises ShipIt's ability to discard previous commands and
-		// install an even newer update.
-		[NSThread sleepForTimeInterval:0.3];
+it(@"should use the application's bundled version of Squirrel and update in-place after a significant delay", ^{
+	NSURL *updateURL = [self createTestApplicationUpdate];
+	SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
+		@"updateURL": zipUpdate(updateURL),
+		@"final": @YES
+	} error:NULL];
 
-		update = [SQRLTestUpdate modelWithDictionary:@{
-			@"updateURL": zipUpdate(updateURL),
-			@"final": @YES
-		} error:NULL];
+	writeUpdate(update);
 
-		writeUpdate(update);
+	NSTimeInterval delay = 30;
+	NSRunningApplication *app = launchWithEnvironment(@{ @"SQRLUpdateDelay": [NSString stringWithFormat:@"%f", delay] });
 
-		expect(@(app.terminated)).withTimeout(SQRLLongTimeout).toEventually(beTruthy());
-		expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
-	});
+	Expecta.asynchronousTestTimeout = delay + 3;
+	expect(app.terminated).will.beTruthy();
 
-	it(@"should use the application's bundled version of Squirrel and update in-place after a significant delay", ^{
-		SKIP_IF_RUNNING_ON_TRAVIS
-		
-		SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
-			@"updateURL": zipUpdate(updateURL),
-			@"final": @YES
-		} error:NULL];
-
-		writeUpdate(update);
-
-		NSTimeInterval delay = 15;
-		NSRunningApplication *app = launchWithEnvironment(@{ @"SQRLUpdateDelay": [NSString stringWithFormat:@"%f", delay] });
-
-		expect(@(app.terminated)).withTimeout(delay + SQRLLongTimeout).toEventually(beTruthy());
-		expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
-	});
-
-	describe(@"cleaning up", ^{
-		__block NSURL *appSupportURL;
-		__block RACSignal *updateDirectoryURLs;
-
-		beforeEach(^{
-			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:@"com.github.Squirrel.TestApplication.ShipIt"];
-
-			appSupportURL = [[directoryManager storageURL] first];
-			expect(appSupportURL).notTo(beNil());
-
-			updateDirectoryURLs = [[RACSignal
-				defer:^{
-					NSArray *contents = [NSFileManager.defaultManager contentsOfDirectoryAtURL:appSupportURL includingPropertiesForKeys:nil options:0 error:NULL];
-					if (contents == nil) return [RACSignal empty];
-
-					return contents.rac_sequence.signal;
-				}]
-				filter:^(NSURL *directoryURL) {
-					return [directoryURL.lastPathComponent hasPrefix:@"update."];
-				}];
-		});
-
-		it(@"should remove downloaded archives after updating", ^{
-			SKIP_IF_RUNNING_ON_TRAVIS
-
-			NSError *error = nil;
-			SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
-				@"updateURL": zipUpdate(updateURL),
-				@"final": @YES
-			} error:&error];
-
-			expect(update).notTo(beNil());
-			expect(error).to(beNil());
-
-			writeUpdate(update);
-
-			NSRunningApplication *app = launchWithEnvironment(@{ @"SQRLUpdateRequestCount": @2 });
-			expect([updateDirectoryURLs toArray]).toEventuallyNot(equal(@[]));
-			expect(@(app.terminated)).withTimeout(SQRLLongTimeout).toEventually(beTruthy());
-			expect(self.testApplicationBundleVersion).toEventually(equal(SQRLTestApplicationUpdatedShortVersionString));
-
-			expect([updateDirectoryURLs toArray]).toEventually(equal(@[]));
-		});
-	});
+	expect(self.testApplicationBundleVersion).will.equal(SQRLTestApplicationUpdatedShortVersionString);
 });
 
 describe(@"response handling", ^{
 	__block NSURLRequest *localRequest = nil;
 	__block SQRLUpdater *updater = nil;
 
-	beforeEach(^{
+	before(^{
 		localRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:@"fake://host/path"]];
 		updater = [[SQRLUpdater alloc] initWithUpdateRequest:localRequest];
 	});
@@ -218,10 +158,10 @@ describe(@"response handling", ^{
 		}];
 
 		NSError *error = nil;
-		BOOL result = [[updater.checkForUpdatesCommand execute:nil] asynchronouslyWaitUntilCompleted:&error];
-		expect(@(result)).to(beFalsy());
-		expect(error.domain).to(equal(SQRLUpdaterErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLUpdaterErrorInvalidServerResponse)));
+		BOOL result = [[updater.checkForUpdatesAction deferred] asynchronouslyWaitUntilCompleted:&error];
+		expect(result).to.beFalsy();
+		expect(error.domain).to.equal(SQRLUpdaterErrorDomain);
+		expect(error.code).to.equal(SQRLUpdaterErrorInvalidServerResponse);
 	});
 
 	it(@"should return an error for non JSON data", ^{
@@ -235,73 +175,90 @@ describe(@"response handling", ^{
 		}];
 
 		NSError *error = nil;
-		BOOL result = [[updater.checkForUpdatesCommand execute:nil] asynchronouslyWaitUntilCompleted:&error];
-		expect(@(result)).to(beFalsy());
-		expect(error.domain).to(equal(SQRLUpdaterErrorDomain));
-		expect(@(error.code)).to(equal(@(SQRLUpdaterErrorInvalidServerBody)));
+		BOOL result = [[updater.checkForUpdatesAction deferred] asynchronouslyWaitUntilCompleted:&error];
+		expect(result).to.beFalsy();
+		expect(error.domain).to.equal(SQRLUpdaterErrorDomain);
+		expect(error.code).to.equal(SQRLUpdaterErrorInvalidServerBody);
 	});
 });
 
-static RACSignal * (^stateNotificationListener)(void) = ^ {
-	return [[[NSDistributedNotificationCenter.defaultCenter
-		rac_addObserverForName:SQRLTestAppUpdaterStateTransitionNotificationName object:nil]
+it(@"should clean up resumable downloads after a successful download", ^{
+	SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:@"com.github.Squirrel.TestApplication"];
+	SQRLDownloadManager *downloadManager = [[SQRLDownloadManager alloc] initWithDirectoryManager:directoryManager];
+
+	NSError *error = nil;
+	BOOL remove = [[downloadManager removeAllResumableDownloads] asynchronouslyWaitUntilCompleted:&error];
+	expect(remove).to.beTruthy();
+	expect(error).to.beNil();
+
+	NSURL *updateApplicationBundle = [self createTestApplicationUpdate];
+
+	NSURL *firstDownload = zipUpdate(updateApplicationBundle);
+	SQRLURLConnection *connection = [[SQRLURLConnection alloc] initWithRequest:[NSURLRequest requestWithURL:firstDownload]];
+	BOOL download = [[connection download:downloadManager] asynchronouslyWaitUntilCompleted:&error];
+	expect(download).to.beTruthy();
+	expect(error).to.beNil();
+
+	NSURL *downloadDirectory = [[directoryManager downloadDirectoryURL] firstOrDefault:nil success:NULL error:&error];
+	expect(downloadDirectory).notTo.beNil();
+	expect(error).to.beNil();
+
+	NSArray *contents = [NSFileManager.defaultManager contentsOfDirectoryAtURL:downloadDirectory includingPropertiesForKeys:@[] options:0 error:&error];
+	expect(contents.count).to.equal(1);
+
+	SQRLTestUpdate *update = [[SQRLTestUpdate alloc] initWithDictionary:@{
+		@"updateURL": zipUpdate(updateApplicationBundle),
+		@"final": @YES,
+	} error:NULL];
+
+	writeUpdate(update);
+
+	NSRunningApplication *app = launchWithEnvironment(nil);
+	expect(app.terminated).will.beTruthy();
+	expect(self.testApplicationBundleVersion).will.equal(SQRLTestApplicationUpdatedShortVersionString);
+
+	contents = [NSFileManager.defaultManager contentsOfDirectoryAtURL:downloadDirectory includingPropertiesForKeys:@[] options:0 error:&error];
+	if (contents == nil) {
+		expect(error.domain).to.equal(NSCocoaErrorDomain);
+		expect(error.code).to.equal(NSFileReadNoSuchFileError);
+	} else {
+		expect(contents.count).to.equal(0);
+	}
+});
+
+it(@"should unpack update archives into a .noindex directory", ^{
+	NSURL *zippedUpdateLocation = zipUpdate([self createTestApplicationUpdate]);
+
+	SQRLTestUpdate *update = [[SQRLTestUpdate alloc] initWithDictionary:@{
+		@keypath(update.updateURL): zippedUpdateLocation,
+	} error:NULL];
+
+	writeUpdate(update);
+
+	__block SQRLDownloadedUpdate *downloadedUpdate;
+
+	[[[[[NSDistributedNotificationCenter.defaultCenter
+		rac_addObserverForName:@"com.github.Squirrel.TestApplication.updateReceived" object:nil]
 		map:^(NSNotification *notification) {
-			return notification.userInfo[SQRLTestAppUpdaterStateKey];
+			return notification.userInfo[@"update"];
 		}]
-		setNameWithFormat:@"stateNotificationListener"];
-};
-
-describe(@"state", ^{
-	it(@"should transition through idle, checking and idle, when there is no update", ^{
-		SKIP_IF_RUNNING_ON_TRAVIS
-
-		NSMutableArray *states = [NSMutableArray array];
-		[stateNotificationListener() subscribeNext:^(NSNumber *state) {
-			[states addObject:state];
+		tryMap:^(NSString *serialisedUpdate, NSError **errorRef) {
+			NSData *JSONData = [serialisedUpdate dataUsingEncoding:NSUTF8StringEncoding];
+			return [NSJSONSerialization JSONObjectWithData:JSONData options:0 error:errorRef];
+		}]
+		tryMap:^(NSDictionary *JSONDictionary, NSError **errorRef) {
+			return [MTLJSONAdapter modelOfClass:SQRLDownloadedUpdate.class fromJSONDictionary:JSONDictionary error:errorRef];
+		}]
+		subscribeNext:^(SQRLDownloadedUpdate *update) {
+			downloadedUpdate = update;
 		}];
 
-		NSRunningApplication *testApplication = launchWithEnvironment(nil);
+	launchWithEnvironment(nil);
 
-		NSArray *expectedStates = @[
-			@(SQRLUpdaterStateIdle),
-			@(SQRLUpdaterStateCheckingForUpdate),
-			@(SQRLUpdaterStateIdle),
-		];
-		expect(states).toEventually(equal(expectedStates));
+	expect(downloadedUpdate).willNot.beNil();
 
-		expect(@(testApplication.terminated)).withTimeout(SQRLLongTimeout).toEventually(beTruthy());
-	});
-
-	it(@"should transition through idle, checking, downloading and awaiting relaunch, when there is an update", ^{
-		SKIP_IF_RUNNING_ON_TRAVIS
-
-		NSMutableArray *states = [NSMutableArray array];
-		[stateNotificationListener() subscribeNext:^(NSNumber *state) {
-			[states addObject:state];
-		}];
-
-		NSError *error;
-		SQRLTestUpdate *update = [SQRLTestUpdate modelWithDictionary:@{
-			@"updateURL": zipUpdate([self createTestApplicationUpdate]),
-			@"final": @YES,
-		} error:&error];
-		expect(update).notTo(beNil());
-		expect(error).to(beNil());
-
-		writeUpdate(update);
-
-		NSRunningApplication *testApplication = launchWithEnvironment(nil);
-
-		NSArray *expectedStates = @[
-			@(SQRLUpdaterStateIdle),
-			@(SQRLUpdaterStateCheckingForUpdate),
-			@(SQRLUpdaterStateDownloadingUpdate),
-			@(SQRLUpdaterStateAwaitingRelaunch),
-		];
-		expect(states).withTimeout(SQRLLongTimeout).toEventually(equal(expectedStates));
-
-		expect(@(testApplication.terminated)).withTimeout(SQRLLongTimeout).toEventually(beTruthy());
-	});
+	NSURL *bundleURL = downloadedUpdate.bundle.bundleURL;
+	expect([bundleURL.path rangeOfString:@".noindex"].location).notTo.equal(NSNotFound);
 });
 
-QuickSpecEnd
+SpecEnd

SquirrelTests/SQRLZipArchiverSpec.m

@@ -6,44 +6,38 @@
 //  Copyright (c) 2013 GitHub. All rights reserved.
 //
 
-#import <Nimble/Nimble.h>
-#import <Quick/Quick.h>
-#import <ReactiveCocoa/ReactiveCocoa.h>
-#import <Squirrel/Squirrel.h>
-
-#import "QuickSpec+SQRLFixtures.h"
 #import "SQRLCodeSignature.h"
 #import "SQRLZipArchiver.h"
 
-QuickSpecBegin(SQRLZipArchiverSpec)
+SpecBegin(SQRLZipOperation)
 
 it(@"should extract a zip archive created by the Finder", ^{
 	NSURL *zipURL = [[NSBundle bundleForClass:self.class] URLForResource:@"TestApplication.app" withExtension:@"zip"];
 
 	NSError *error = nil;
 	BOOL success = [[SQRLZipArchiver unzipArchiveAtURL:zipURL intoDirectoryAtURL:self.temporaryDirectoryURL] asynchronouslyWaitUntilCompleted:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
 
 	NSURL *extractedAppURL = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"TestApplication 2.1.app"];
-	expect(@([NSFileManager.defaultManager fileExistsAtPath:extractedAppURL.path])).to(beTruthy());
+	expect([NSFileManager.defaultManager fileExistsAtPath:extractedAppURL.path]).to.beTruthy();
 
 	success = [[self.testApplicationSignature verifyBundleAtURL:extractedAppURL] waitUntilCompleted:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
 });
 
 it(@"should fail to extract a nonexistent zip archive", ^{
 	NSError *error = nil;
 	BOOL success = [[SQRLZipArchiver unzipArchiveAtURL:[self.temporaryDirectoryURL URLByAppendingPathComponent:@"foo.zip"] intoDirectoryAtURL:self.temporaryDirectoryURL] asynchronouslyWaitUntilCompleted:&error];
-	expect(@(success)).to(beFalsy());
+	expect(success).to.beFalsy();
 
 	NSLog(@"%@", error);
 
-	expect(error).notTo(beNil());
-	expect(error.domain).to(equal(SQRLZipArchiverErrorDomain));
-	expect(@(error.code)).to(equal(@(SQRLZipArchiverShellTaskFailed)));
-	expect(error.userInfo[SQRLZipArchiverExitCodeErrorKey]).notTo(equal(0));
+	expect(error).notTo.beNil();
+	expect(error.domain).to.equal(SQRLZipArchiverErrorDomain);
+	expect(error.code).to.equal(SQRLZipArchiverShellTaskFailed);
+	expect(error.userInfo[SQRLZipArchiverExitCodeErrorKey]).notTo.equal(0);
 });
 
 it(@"should create a zip archive readable by itself", ^{
@@ -51,21 +45,21 @@ it(@"should create a zip archive readable by itself", ^{
 
 	NSError *error = nil;
 	BOOL success = [[SQRLZipArchiver createZipArchiveAtURL:zipURL fromDirectoryAtURL:self.testApplicationURL] asynchronouslyWaitUntilCompleted:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
 
-	expect(@([NSFileManager.defaultManager fileExistsAtPath:zipURL.path])).to(beTruthy());
+	expect([NSFileManager.defaultManager fileExistsAtPath:zipURL.path]).to.beTruthy();
 
 	success = [[SQRLZipArchiver unzipArchiveAtURL:zipURL intoDirectoryAtURL:self.temporaryDirectoryURL] asynchronouslyWaitUntilCompleted:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
 
 	NSURL *extractedAppURL = [self.temporaryDirectoryURL URLByAppendingPathComponent:@"TestApplication.app"];
-	expect(@([NSFileManager.defaultManager fileExistsAtPath:extractedAppURL.path])).to(beTruthy());
+	expect([NSFileManager.defaultManager fileExistsAtPath:extractedAppURL.path]).to.beTruthy();
 
 	success = [[self.testApplicationSignature verifyBundleAtURL:extractedAppURL] waitUntilCompleted:&error];
-	expect(@(success)).to(beTruthy());
-	expect(error).to(beNil());
+	expect(success).to.beTruthy();
+	expect(error).to.beNil();
 });
 
-QuickSpecEnd
+SpecEnd

SquirrelTests/SquirrelTests-Info.plist

@@ -7,7 +7,7 @@
 	<key>CFBundleExecutable</key>
 	<string>${EXECUTABLE_NAME}</string>
 	<key>CFBundleIdentifier</key>
-	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<string>com.github.${PRODUCT_NAME:rfc1034identifier}</string>
 	<key>CFBundleInfoDictionaryVersion</key>
 	<string>6.0</string>
 	<key>CFBundlePackageType</key>

SquirrelTests/SquirrelTests-Prefix.pch

@@ -0,0 +1,25 @@
+//
+//  SquirrelTests-Prefix.pch
+//  Squirrel
+//
+//  Created by Justin Spahr-Summers on 2013-07-21.
+//  Copyright (c) 2013 GitHub. All rights reserved.
+//
+
+#ifdef __OBJC__
+	#import <Cocoa/Cocoa.h>
+	#import <SenTestingKit/SenTestingKit.h>
+
+	#import <Mantle/Mantle.h>
+	#import <ReactiveCocoa/ReactiveCocoa.h>
+	#import <ReactiveCocoa/EXTScope.h>
+	#import <Squirrel/Squirrel.h>
+
+	#define SPT_SUBCLASS SQRLTestCase
+	#import "Specta.h"
+
+	#define EXP_SHORTHAND
+	#import "Expecta.h"
+
+	#import "SQRLTestCase.h"
+#endif

SquirrelTests/SwiftSpec.swift

@@ -1,19 +0,0 @@
-//
-//  SwiftSpec.swift
-//  ReactiveCocoa
-//
-//  Created by Justin Spahr-Summers on 2014-10-14.
-//  Copyright (c) 2014 GitHub. All rights reserved.
-//
-
-import Foundation
-import Nimble
-import Quick
-
-// Without this, the Swift stdlib won't be linked into the test target (even if
-// “Embedded Content Contains Swift Code” is enabled).
-class SwiftSpec: QuickSpec {
-	override func spec() {
-		expect(true).to(beTruthy())
-	}
-}

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Headers

@@ -1 +0,0 @@
-Versions/Current/Headers

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Mantle

@@ -1 +0,0 @@
-Versions/Current/Mantle

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Modules

@@ -1 +0,0 @@
-Versions/Current/Modules

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Resources

@@ -1 +0,0 @@
-Versions/Current/Resources

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Versions/A/Headers/MTLJSONAdapter.h

@@ -1,172 +0,0 @@
-//
-//  MTLJSONAdapter.h
-//  Mantle
-//
-//  Created by Justin Spahr-Summers on 2013-02-12.
-//  Copyright (c) 2013 GitHub. All rights reserved.
-//
-
-#import <Foundation/Foundation.h>
-
-@class MTLModel;
-
-// A MTLModel object that supports being parsed from and serialized to JSON.
-@protocol MTLJSONSerializing
-@required
-
-// Specifies how to map property keys to different key paths in JSON.
-//
-// Subclasses overriding this method should combine their values with those of
-// `super`.
-//
-// Any property keys not present in the dictionary are assumed to match the JSON
-// key that should be used. Any keys associated with NSNull will not participate
-// in JSON serialization.
-//
-// Returns a dictionary mapping property keys to JSON key paths (as strings) or
-// NSNull values.
-+ (NSDictionary *)JSONKeyPathsByPropertyKey;
-
-@optional
-
-// Specifies how to convert a JSON value to the given property key. If
-// reversible, the transformer will also be used to convert the property value
-// back to JSON.
-//
-// If the receiver implements a `+<key>JSONTransformer` method, MTLJSONAdapter
-// will use the result of that method instead.
-//
-// Returns a value transformer, or nil if no transformation should be performed.
-+ (NSValueTransformer *)JSONTransformerForKey:(NSString *)key;
-
-// Overridden to parse the receiver as a different class, based on information
-// in the provided dictionary.
-//
-// This is mostly useful for class clusters, where the abstract base class would
-// be passed into -[MTLJSONAdapter initWithJSONDictionary:modelClass:], but
-// a subclass should be instantiated instead.
-//
-// JSONDictionary - The JSON dictionary that will be parsed.
-//
-// Returns the class that should be parsed (which may be the receiver), or nil
-// to abort parsing (e.g., if the data is invalid).
-+ (Class)classForParsingJSONDictionary:(NSDictionary *)JSONDictionary;
-
-@end
-
-// The domain for errors originating from MTLJSONAdapter.
-extern NSString * const MTLJSONAdapterErrorDomain;
-
-// +classForParsingJSONDictionary: returned nil for the given dictionary.
-extern const NSInteger MTLJSONAdapterErrorNoClassFound;
-
-// The provided JSONDictionary is not valid.
-extern const NSInteger MTLJSONAdapterErrorInvalidJSONDictionary;
-
-// The model's implementation of +JSONKeyPathsByPropertyKey included a key which
-// does not actually exist in +propertyKeys.
-extern const NSInteger MTLJSONAdapterErrorInvalidJSONMapping;
-
-// Converts a MTLModel object to and from a JSON dictionary.
-@interface MTLJSONAdapter : NSObject
-
-// The model object that the receiver was initialized with, or that the receiver
-// parsed from a JSON dictionary.
-@property (nonatomic, strong, readonly) MTLModel<MTLJSONSerializing> *model;
-
-// Attempts to parse a JSON dictionary into a model object.
-//
-// modelClass     - The MTLModel subclass to attempt to parse from the JSON.
-//                  This class must conform to <MTLJSONSerializing>. This
-//                  argument must not be nil.
-// JSONDictionary - A dictionary representing JSON data. This should match the
-//                  format returned by NSJSONSerialization. If this argument is
-//                  nil, the method returns nil.
-// error          - If not NULL, this may be set to an error that occurs during
-//                  parsing or initializing an instance of `modelClass`.
-//
-// Returns an instance of `modelClass` upon success, or nil if a parsing error
-// occurred.
-+ (id)modelOfClass:(Class)modelClass fromJSONDictionary:(NSDictionary *)JSONDictionary error:(NSError **)error;
-
-// Attempts to parse an array of JSON dictionary objects into a model objects
-// of a specific class.
-//
-// modelClass - The MTLModel subclass to attempt to parse from the JSON. This
-//              class must conform to <MTLJSONSerializing>. This argument must
-//              not be nil.
-// JSONArray  - A array of dictionaries representing JSON data. This should
-//              match the format returned by NSJSONSerialization. If this
-//              argument is nil, the method returns nil.
-// error      - If not NULL, this may be set to an error that occurs during
-//              parsing or initializing an any of the instances of
-//              `modelClass`.
-//
-// Returns an array of `modelClass` instances upon success, or nil if a parsing
-// error occurred.
-+ (NSArray *)modelsOfClass:(Class)modelClass fromJSONArray:(NSArray *)JSONArray error:(NSError **)error;
-
-// Converts a model into a JSON representation.
-//
-// model - The model to use for JSON serialization. This argument must not be
-//         nil.
-//
-// Returns a JSON dictionary, or nil if a serialization error occurred.
-+ (NSDictionary *)JSONDictionaryFromModel:(MTLModel<MTLJSONSerializing> *)model;
-
-// Converts a array of models into a JSON representation.
-//
-// models - The array of models to use for JSON serialization. This argument
-//          must not be nil.
-//
-// Returns a JSON array, or nil if a serialization error occurred for any
-// model.
-+ (NSArray *)JSONArrayFromModels:(NSArray *)models;
-
-// Initializes the receiver by attempting to parse a JSON dictionary into
-// a model object.
-//
-// JSONDictionary - A dictionary representing JSON data. This should match the
-//                  format returned by NSJSONSerialization. If this argument is
-//                  nil, the method returns nil and an error with code
-//                  MTLJSONAdapterErrorInvalidJSONDictionary.
-// modelClass     - The MTLModel subclass to attempt to parse from the JSON.
-//                  This class must conform to <MTLJSONSerializing>. This
-//                  argument must not be nil.
-// error          - If not NULL, this may be set to an error that occurs during
-//                  parsing or initializing an instance of `modelClass`.
-//
-// Returns an initialized adapter upon success, or nil if a parsing error
-// occurred.
-- (id)initWithJSONDictionary:(NSDictionary *)JSONDictionary modelClass:(Class)modelClass error:(NSError **)error;
-
-// Initializes the receiver with an existing model.
-//
-// model - The model to use for JSON serialization. This argument must not be
-//         nil.
-- (id)initWithModel:(MTLModel<MTLJSONSerializing> *)model;
-
-// Serializes the receiver's `model` into JSON.
-//
-// Returns a JSON dictionary, or nil if a serialization error occurred.
-- (NSDictionary *)JSONDictionary;
-
-// Looks up the JSON key path in the model's +propertyKeys.
-//
-// Subclasses may override this method to customize the adapter's seralizing
-// behavior. You should not call this method directly.
-//
-// key - The property key to retrieve the corresponding JSON key path for. This
-//       argument must not be nil.
-//
-// Returns a key path to use, or nil to omit the property from JSON.
-- (NSString *)JSONKeyPathForPropertyKey:(NSString *)key;
-
-@end
-
-@interface MTLJSONAdapter (Deprecated)
-
-+ (id)modelOfClass:(Class)modelClass fromJSONDictionary:(NSDictionary *)JSONDictionary __attribute__((deprecated("Replaced by +modelOfClass:fromJSONDictionary:error:")));
-- (id)initWithJSONDictionary:(NSDictionary *)JSONDictionary modelClass:(Class)modelClass __attribute__((deprecated("Replaced by -initWithJSONDictionary:modelClass:error:")));
-
-@end

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Versions/A/Headers/MTLManagedObjectAdapter.h

@@ -1,215 +0,0 @@
-//
-//  MTLManagedObjectAdapter.h
-//  Mantle
-//
-//  Created by Justin Spahr-Summers on 2013-03-29.
-//  Copyright (c) 2013 GitHub. All rights reserved.
-//
-
-#import <CoreData/CoreData.h>
-
-@class MTLModel;
-
-// A MTLModel object that supports being serialized to and from Core Data as an
-// NSManagedObject.
-@protocol MTLManagedObjectSerializing
-@required
-
-// The name of the Core Data entity that the receiver serializes to and
-// deserializes from.
-//
-// This method must not return nil.
-+ (NSString *)managedObjectEntityName;
-
-// Specifies how to map property keys to different keys on the receiver's
-// +managedObjectEntity.
-//
-// Entity attributes will be mapped to and from the receiver's properties using
-// +entityAttributeTransformerForKey:. Entity relationships will be mapped to
-// and from MTLModel objects using +relationshipModelClassesByPropertyKey.
-// Fetched properties are not supported.
-//
-// Subclasses overriding this method should combine their values with those of
-// `super`.
-//
-// Any property keys not present in the dictionary are assumed to match the
-// entity key that should be used. Any keys associated with NSNull will not
-// participate in managed object serialization.
-//
-// Returns a dictionary mapping property keys to entity keys (as strings) or
-// NSNull values.
-+ (NSDictionary *)managedObjectKeysByPropertyKey;
-
-@optional
-
-// Specifies a set of property keys used by the adapter to check for an already
-// existing managed object when converting the MTLModel to its related
-// NSManagedObject.
-//
-// The adapter will first map any keys provided by this method to the correct
-// keys in managedObjectKeysByPropertyKey.
-//
-// The adapter will then perform a fetch request in the provided context for a
-// managed object that matches the MTLModel's managedObjectEntityName and has
-// equal values set for the property keys on the MTLModel.
-//
-// The managed object returned by the fetch request will then be set with all
-// values from the MTLModel that the managed object is being converted from.
-//
-// If a property value of our MTLModel is yet another MTLModel which needs to be
-// converted to a managed object, the class for that MTLModel can also implement
-// this method to perform its own uniqing.
-//
-// For example:
-// 1. An MTLModel subclass has id_number = 10.
-// 2. An NSManagedObject accessible to the adapter's context has idnumber = 10.
-// 3. managedObjectKeysByPropertyKey returns @{@"id_number" : @"idnumber"}
-// 4. propertyKeysForManagedObjectUniquing returns
-//    [NSSet setWithObject:@"id_number"];
-// 5. Then our fetch request may return this managed object (or another managed
-//    object with idnumber = 10).
-//
-// NOTE: If multiple managed objects follow the same uniquing criteria only one
-// of them will be set with our MTLModel's values.
-+ (NSSet *)propertyKeysForManagedObjectUniquing;
-
-// Specifies how to convert the given property key to a managed object
-// attribute. If reversible, the transformer will also be used to convert the
-// managed object attribute back to the property.
-//
-// If the receiver implements a `+<key>EntityAttributeTransformer` method,
-// MTLManagedObjectAdapter will use the result of that method instead.
-//
-// Returns a value transformer, or nil if no transformation should be performed.
-+ (NSValueTransformer *)entityAttributeTransformerForKey:(NSString *)key;
-
-// Specifies the MTLModel subclasses that should be deserialized to the
-// receiver's property keys when a property key corresponds to an entity
-// relationship.
-//
-// In other words, the dictionary returned by this method is used to decode
-// managed object relationships into MTLModels (or NSArrays or NSSets thereof)
-// set on the receiver.
-//
-// If a property key is omitted from the returned dictionary, but present in
-// +managedObjectKeysByPropertyKey, and the receiver's +managedObjectEntity has
-// a relationship at the corresponding key, an exception will be thrown during
-// deserialization.
-//
-// Subclasses overriding this method should combine their values with those of
-// `super`.
-//
-// Returns a dictionary mapping property keys to the Class objects that should
-// be used.
-+ (NSDictionary *)relationshipModelClassesByPropertyKey;
-
-// Overridden to deserialize a different class instead of the receiver, based on
-// information in the provided object.
-//
-// This is mostly useful for class clusters, where the abstract base class would
-// be passed into +[MTLManagedObjectAdapter
-// modelOfClass:fromManagedObject:error:], but a subclass should be instantiated
-// instead.
-//
-// managedObject - The object that will be deserialized.
-//
-// Returns the class that should be instantiated (which may be the receiver), or
-// nil to abort parsing (e.g., if the data is invalid).
-+ (Class)classForDeserializingManagedObject:(NSManagedObject *)managedObject;
-
-// Overriden when merging the value of the given key on the receiver with the
-// value of the same key from the given `NSManagedObject` requires custom
-// handling.
-//
-// By default, this method is not implemented, and precedence will be given to
-// the value of the receiving model implicitly.
-//
-// When implemented, this method is called when an existing `NSManagedObject`
-// is found for the receiving model, before updating the `NSManagedObject`'s
-// properties.
-//
-// When implementing, you should use `+managedObjectKeysByPropertyKey` to map
-// the given `key` to the appropriate `NSManagedObject` property.
-- (void)mergeValueForKey:(NSString *)key fromManagedObject:(NSManagedObject *)managedObject;
-
-// Overriden when merging values on the receiver with the given
-// `NSManagedObject` requires custom handling.
-//
-// By default, this method is not implemented, and precedence will be given to
-// the values of the receiving model implicitly.
-//
-// When implemented, this method is called when an existing `NSManagedObject`
-// is found for the receiving model, before updating the `NSManagedObject`'s
-// properties.
-//
-// When implementing, you should use `+managedObjectKeysByPropertyKey` to map
-// the given `key` to the appropriate `NSManagedObject` property.
-//
-// If you have also implemented `mergeValueForKey:fromManagedObject:` you have
-// to make sure to call `mergeValueForKey:fromManagedObject:` from this method
-// when appropriate.
-- (void)mergeValuesForKeysFromManagedObject:(NSManagedObject *)managedObject;
-
-@end
-
-// The domain for errors originating from MTLManagedObjectAdapter.
-extern NSString * const MTLManagedObjectAdapterErrorDomain;
-
-// +classForDeserializingManagedObject: returned nil for the given object.
-extern const NSInteger MTLManagedObjectAdapterErrorNoClassFound;
-
-// An NSManagedObject failed to initialize.
-extern const NSInteger MTLManagedObjectAdapterErrorInitializationFailed;
-
-// The managed object key specified by +managedObjectKeysByPropertyKey does not
-// exist in the NSEntityDescription.
-extern const NSInteger MTLManagedObjectAdapterErrorInvalidManagedObjectKey;
-
-// The managed object property specified has a type that isn't supported by
-// MTLManagedObjectAdapter.
-extern const NSInteger MTLManagedObjectAdapterErrorUnsupportedManagedObjectPropertyType;
-
-// The fetch request to find an existing managed object based on
-// `+propertyKeysForManagedObjectUniquing` failed.
-extern const NSInteger MTLManagedObjectAdapterErrorUniqueFetchRequestFailed;
-
-// A MTLModel property cannot be serialized to or deserialized from an
-// NSManagedObject relationship.
-//
-// For a to-one relationship, this means that the property does not contain
-// a MTLModel, or the MTLModel does not conform to <MTLManagedObjectSerializing>.
-//
-// For a to-many relationship, this means that the property does not contain an
-// NSArray or NSSet of MTLModel<MTLManagedObjectSerializing> instances.
-extern const NSInteger MTLManagedObjectAdapterErrorUnsupportedRelationshipClass;
-
-// The model's implementation of +managedObjectKeysByPropertyKey included a key
-// which does not actually exist in +propertyKeys.
-extern const NSInteger MTLManagedObjectAdapterErrorInvalidManagedObjectMapping;
-
-// Converts a MTLModel object to and from an NSManagedObject.
-@interface MTLManagedObjectAdapter : NSObject
-
-// Attempts to deserialize an NSManagedObject into a MTLModel object.
-//
-// modelClass    - The MTLModel subclass to return. This class must conform to
-//                 <MTLManagedObjectSerializing>. This argument must not be nil.
-// managedObject - The managed object to deserialize. If this argument is nil,
-//                 the method returns nil.
-// error         - If not NULL, this may be set to an error that occurs during
-//                 deserialization or initializing an instance of `modelClass`.
-//
-// Returns an instance of `modelClass` upon success, or nil if an error
-// occurred.
-+ (id)modelOfClass:(Class)modelClass fromManagedObject:(NSManagedObject *)managedObject error:(NSError **)error;
-
-// Serializes a MTLModel into an NSManagedObject.
-//
-// model   - The model object to serialize. This argument must not be nil.
-// context - The context into which to insert the created managed object. This
-//           argument must not be nil.
-// error   - If not NULL, this may be set to an error that occurs during
-//           serialization or insertion.
-+ (id)managedObjectFromModel:(MTLModel<MTLManagedObjectSerializing> *)model insertingIntoContext:(NSManagedObjectContext *)context error:(NSError **)error;
-
-@end

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Versions/A/Headers/MTLModel+NSCoding.h

@@ -1,128 +0,0 @@
-//
-//  MTLModel+NSCoding.h
-//  Mantle
-//
-//  Created by Justin Spahr-Summers on 2013-02-12.
-//  Copyright (c) 2013 GitHub. All rights reserved.
-//
-
-#import "MTLModel.h"
-
-// Defines how a MTLModel property key should be encoded into an archive.
-//
-// MTLModelEncodingBehaviorExcluded      - The property should never be encoded.
-// MTLModelEncodingBehaviorUnconditional - The property should always be
-//                                         encoded.
-// MTLModelEncodingBehaviorConditional   - The object should be encoded only
-//                                         if unconditionally encoded elsewhere.
-//                                         This should only be used for object
-//                                         properties.
-typedef enum : NSUInteger {
-    MTLModelEncodingBehaviorExcluded = 0,
-    MTLModelEncodingBehaviorUnconditional,
-    MTLModelEncodingBehaviorConditional,
-} MTLModelEncodingBehavior;
-
-// Implements default archiving and unarchiving behaviors for MTLModel.
-@interface MTLModel (NSCoding) <NSCoding>
-
-// Initializes the receiver from an archive.
-//
-// This will decode the original +modelVersion of the archived object, then
-// invoke -decodeValueForKey:withCoder:modelVersion: for each of the receiver's
-// +propertyKeys.
-//
-// Returns an initialized model object, or nil if a decoding error occurred.
-- (id)initWithCoder:(NSCoder *)coder;
-
-// Archives the receiver using the given coder.
-//
-// This will encode the receiver's +modelVersion, then the receiver's properties
-// according to the behaviors specified in +encodingBehaviorsByPropertyKey.
-- (void)encodeWithCoder:(NSCoder *)coder;
-
-// Determines how the +propertyKeys of the class are encoded into an archive.
-// The values of this dictionary should be boxed MTLModelEncodingBehavior
-// values.
-//
-// Any keys not present in the dictionary will be excluded from the archive.
-//
-// Subclasses overriding this method should combine their values with those of
-// `super`.
-//
-// Returns a dictionary mapping the receiver's +propertyKeys to default encoding
-// behaviors. If a property is an object with `weak` semantics, the default
-// behavior is MTLModelEncodingBehaviorConditional; otherwise, the default is
-// MTLModelEncodingBehaviorUnconditional.
-+ (NSDictionary *)encodingBehaviorsByPropertyKey;
-
-// Determines the classes that are allowed to be decoded for each of the
-// receiver's properties when using <NSSecureCoding>. The values of this
-// dictionary should be NSArrays of Class objects.
-//
-// If any encodable keys (as determined by +encodingBehaviorsByPropertyKey) are
-// not present in the dictionary, an exception will be thrown during secure
-// encoding or decoding.
-//
-// Subclasses overriding this method should combine their values with those of
-// `super`.
-//
-// Returns a dictionary mapping the receiver's encodable keys (as determined by
-// +encodingBehaviorsByPropertyKey) to default allowed classes, based on the
-// type that each property is declared as. If type of an encodable property
-// cannot be determined (e.g., it is declared as `id`), it will be omitted from
-// the dictionary, and subclasses must provide a valid value to prevent an
-// exception being thrown during encoding/decoding.
-+ (NSDictionary *)allowedSecureCodingClassesByPropertyKey;
-
-// Decodes the value of the given property key from an archive.
-//
-// By default, this method looks for a `-decode<Key>WithCoder:modelVersion:`
-// method on the receiver, and invokes it if found.
-//
-// If the custom method is not implemented and `coder` does not require secure
-// coding, `-[NSCoder decodeObjectForKey:]` will be invoked with the given
-// `key`.
-//
-// If the custom method is not implemented and `coder` requires secure coding,
-// `-[NSCoder decodeObjectOfClasses:forKey:]` will be invoked with the
-// information from +allowedSecureCodingClassesByPropertyKey and the given `key`. The
-// receiver must conform to <NSSecureCoding> for this to work correctly.
-//
-// key          - The property key to decode the value for. This argument cannot
-//                be nil.
-// coder        - The NSCoder representing the archive being decoded. This
-//                argument cannot be nil.
-// modelVersion - The version of the original model object that was encoded.
-//
-// Returns the decoded and boxed value, or nil if the key was not present.
-- (id)decodeValueForKey:(NSString *)key withCoder:(NSCoder *)coder modelVersion:(NSUInteger)modelVersion;
-
-// The version of this MTLModel subclass.
-//
-// This version number is saved in archives so that later model changes can be
-// made backwards-compatible with old versions.
-//
-// Subclasses should override this method to return a higher version number
-// whenever a breaking change is made to the model.
-//
-// Returns 0.
-+ (NSUInteger)modelVersion;
-
-@end
-
-// This method must be overridden to support archives created by older versions
-// of Mantle (before the `MTLModel+NSCoding` interface existed).
-@interface MTLModel (OldArchiveSupport)
-
-// Converts an archived external representation to a dictionary suitable for
-// passing to -initWithDictionary:.
-//
-// externalRepresentation - The decoded external representation of the receiver.
-// fromVersion            - The model version at the time the external
-//                          representation was encoded.
-//
-// Returns nil by default, indicating that conversion failed.
-+ (NSDictionary *)dictionaryValueFromArchivedExternalRepresentation:(NSDictionary *)externalRepresentation version:(NSUInteger)fromVersion;
-
-@end

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Versions/A/Headers/MTLModel.h

@@ -1,125 +0,0 @@
-//
-//  MTLModel.h
-//  Mantle
-//
-//  Created by Justin Spahr-Summers on 2012-09-11.
-//  Copyright (c) 2012 GitHub. All rights reserved.
-//
-
-#import <Foundation/Foundation.h>
-
-// An abstract base class for model objects, using reflection to provide
-// sensible default behaviors.
-//
-// The default implementations of <NSCopying>, -hash, and -isEqual: make use of
-// the +propertyKeys method.
-@interface MTLModel : NSObject <NSCopying>
-
-// Returns a new instance of the receiver initialized using
-// -initWithDictionary:error:.
-+ (instancetype)modelWithDictionary:(NSDictionary *)dictionaryValue error:(NSError **)error;
-
-// Initializes the receiver with default values.
-//
-// This is the designated initializer for this class.
-- (instancetype)init;
-
-// Initializes the receiver using key-value coding, setting the keys and values
-// in the given dictionary.
-//
-// Subclass implementations may override this method, calling the super
-// implementation, in order to perform further processing and initialization
-// after deserialization.
-//
-// dictionaryValue - Property keys and values to set on the receiver. Any NSNull
-//                   values will be converted to nil before being used. KVC
-//                   validation methods will automatically be invoked for all of
-//                   the properties given. If nil, this method is equivalent to
-//                   -init.
-// error           - If not NULL, this may be set to any error that occurs
-//                   (like a KVC validation error).
-//
-// Returns an initialized model object, or nil if validation failed.
-- (instancetype)initWithDictionary:(NSDictionary *)dictionaryValue error:(NSError **)error;
-
-// Returns the keys for all @property declarations, except for `readonly`
-// properties without ivars, or properties on MTLModel itself.
-+ (NSSet *)propertyKeys;
-
-// A dictionary representing the properties of the receiver.
-//
-// The default implementation combines the values corresponding to all
-// +propertyKeys into a dictionary, with any nil values represented by NSNull.
-//
-// This property must never be nil.
-@property (nonatomic, copy, readonly) NSDictionary *dictionaryValue;
-
-// Merges the value of the given key on the receiver with the value of the same
-// key from the given model object, giving precedence to the other model object.
-//
-// By default, this method looks for a `-merge<Key>FromModel:` method on the
-// receiver, and invokes it if found. If not found, and `model` is not nil, the
-// value for the given key is taken from `model`.
-- (void)mergeValueForKey:(NSString *)key fromModel:(MTLModel *)model;
-
-// Merges the values of the given model object into the receiver, using
-// -mergeValueForKey:fromModel: for each key in +propertyKeys.
-//
-// `model` must be an instance of the receiver's class or a subclass thereof.
-- (void)mergeValuesForKeysFromModel:(MTLModel *)model;
-
-// Compares the receiver with another object for equality.
-//
-// The default implementation is equivalent to comparing both models'
-// -dictionaryValue.
-//
-// Note that this may lead to infinite loops if the receiver holds a circular
-// reference to another MTLModel and both use the default behavior.
-// It is recommended to override -isEqual: in this scenario.
-- (BOOL)isEqual:(id)object;
-
-// A string that describes the contents of the receiver.
-//
-// The default implementation is based on the receiver's class and its
-// -dictionaryValue.
-//
-// Note that this may lead to infinite loops if the receiver holds a circular
-// reference to another MTLModel and both use the default behavior.
-// It is recommended to override -description in this scenario.
-- (NSString *)description;
-
-@end
-
-// Implements validation logic for MTLModel.
-@interface MTLModel (Validation)
-
-// Validates the model.
-//
-// The default implementation simply invokes -validateValue:forKey:error: with
-// all +propertyKeys and their current value. If -validateValue:forKey:error:
-// returns a new value, the property is set to that new value.
-//
-// error - If not NULL, this may be set to any error that occurs during
-//         validation
-//
-// Returns YES if the model is valid, or NO if the validation failed.
-- (BOOL)validate:(NSError **)error;
-
-@end
-
-@interface MTLModel (Unavailable)
-
-+ (instancetype)modelWithDictionary:(NSDictionary *)dictionaryValue __attribute__((deprecated("Replaced by +modelWithDictionary:error:")));
-- (instancetype)initWithDictionary:(NSDictionary *)dictionaryValue __attribute__((deprecated("Replaced by -initWithDictionary:error:")));
-
-+ (instancetype)modelWithExternalRepresentation:(NSDictionary *)externalRepresentation __attribute__((deprecated("Replaced by -[MTLJSONAdapter initWithJSONDictionary:modelClass:]")));
-- (instancetype)initWithExternalRepresentation:(NSDictionary *)externalRepresentation __attribute__((deprecated("Replaced by -[MTLJSONAdapter initWithJSONDictionary:modelClass:]")));
-
-@property (nonatomic, copy, readonly) NSDictionary *externalRepresentation __attribute__((deprecated("Replaced by MTLJSONAdapter.JSONDictionary")));
-
-+ (NSDictionary *)externalRepresentationKeyPathsByPropertyKey __attribute__((deprecated("Replaced by +JSONKeyPathsByPropertyKey in <MTLJSONSerializing>")));
-+ (NSValueTransformer *)transformerForKey:(NSString *)key __attribute__((deprecated("Replaced by +JSONTransformerForKey: in <MTLJSONSerializing>")));
-
-+ (NSDictionary *)migrateExternalRepresentation:(NSDictionary *)externalRepresentation fromVersion:(NSUInteger)fromVersion __attribute__((deprecated("Replaced by -decodeValueForKey:withCoder:modelVersion:")));
-
-@end

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Versions/A/Headers/MTLValueTransformer.h

@@ -1,29 +0,0 @@
-//
-//  MTLValueTransformer.h
-//  Mantle
-//
-//  Created by Justin Spahr-Summers on 2012-09-11.
-//  Copyright (c) 2012 GitHub. All rights reserved.
-//
-
-#import <Foundation/Foundation.h>
-
-typedef id (^MTLValueTransformerBlock)(id);
-
-//
-// A value transformer supporting block-based transformation.
-//
-@interface MTLValueTransformer : NSValueTransformer
-
-// Returns a transformer which transforms values using the given block. Reverse
-// transformations will not be allowed.
-+ (instancetype)transformerWithBlock:(MTLValueTransformerBlock)transformationBlock;
-
-// Returns a transformer which transforms values using the given block, for
-// forward or reverse transformations.
-+ (instancetype)reversibleTransformerWithBlock:(MTLValueTransformerBlock)transformationBlock;
-
-// Returns a transformer which transforms values using the given blocks.
-+ (instancetype)reversibleTransformerWithForwardBlock:(MTLValueTransformerBlock)forwardBlock reverseBlock:(MTLValueTransformerBlock)reverseBlock;
-
-@end

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Versions/A/Headers/Mantle.h

@@ -1,26 +0,0 @@
-//
-//  Mantle.h
-//  Mantle
-//
-//  Created by Justin Spahr-Summers on 2012-09-04.
-//  Copyright (c) 2012 GitHub. All rights reserved.
-//
-
-#import <Foundation/Foundation.h>
-
-//! Project version number for Mantle.
-FOUNDATION_EXPORT double MantleVersionNumber;
-
-//! Project version string for Mantle.
-FOUNDATION_EXPORT const unsigned char MantleVersionString[];
-
-#import <Mantle/MTLJSONAdapter.h>
-#import <Mantle/MTLManagedObjectAdapter.h>
-#import <Mantle/MTLModel.h>
-#import <Mantle/MTLModel+NSCoding.h>
-#import <Mantle/MTLValueTransformer.h>
-#import <Mantle/NSArray+MTLManipulationAdditions.h>
-#import <Mantle/NSDictionary+MTLManipulationAdditions.h>
-#import <Mantle/NSObject+MTLComparisonAdditions.h>
-#import <Mantle/NSValueTransformer+MTLInversionAdditions.h>
-#import <Mantle/NSValueTransformer+MTLPredefinedTransformerAdditions.h>

SquirrelTests/TestApplication 2.1.app/Contents/Frameworks/Mantle.framework/Versions/A/Headers/NSArray+MTLManipulationAdditions.h

@@ -1,28 +0,0 @@
-//
-//  NSArray+MTLManipulationAdditions.h
-//  Mantle
-//
-//  Created by Josh Abernathy on 9/19/12.
-//  Copyright (c) 2012 GitHub. All rights reserved.
-//
-
-#import <Foundation/Foundation.h>
-
-@interface NSArray (MTLManipulationAdditions)
-
-// The first object in the array or nil if the array is empty.
-// Forwards to `firstObject` which has been first declared in iOS7, but works with iOS4/10.6.
-@property (nonatomic, readonly, strong) id mtl_firstObject;
-
-// Returns a new array without all instances of the given object.
-- (NSArray *)mtl_arrayByRemovingObject:(id)object;
-
-// Returns a new array without the first object. If the array is empty, it
-// returns the empty array.
-- (NSArray *)mtl_arrayByRemovingFirstObject;
-
-// Returns a new array without the last object. If the array is empty, it
-// returns the empty array.
-- (NSArray *)mtl_arrayByRemovingLastObject;
-
-@end