From c20e8e2d4c88d524aa7fbec44f9b7632611f730a Mon Sep 17 00:00:00 2001
From: Vlad Gorlov <vgorloff@users.noreply.github.com>
Date: Wed, 9 Oct 2019 04:43:35 +0200
Subject: [PATCH] Added Linux support. (#172)

* Added check for os(Linux)

* Sources adopted to Swift Linux Compiler v5.0

* Added Docker configuration to be used for Linux builds.

* Renamed Script.

* Docker configuration update.

* Fixes Linux compile errors.

* Nicification.
---
 LinuxMain.swift                                 |  7 +++++++
 .../Attribute Collections/ColorCollection.swift |  2 +-
 .../Attribute Collections/FontCollection.swift  |  2 +-
 .../ParagraphStyleCollection.swift              |  2 +-
 .../BlockBackgroundColorAttribute.swift         |  2 +-
 .../QuoteStripeAttribute.swift                  |  2 +-
 .../ThematicBreakAttribute.swift                |  2 +-
 .../Helpers/Extensions/CGPoint+Translate.swift  |  4 ++++
 .../Helpers/Extensions/CGRect+Helpers.swift     |  4 ++++
 .../Helpers/Extensions/UIFont+Traits.swift      |  2 +-
 .../Helpers/ListItemParagraphStyler.swift       |  2 +-
 .../DownDebugLayoutManager.swift                |  2 +-
 .../Layout Managers/DownLayoutManager.swift     |  2 +-
 .../AST/Styling/Options/CodeBlockOptions.swift  |  2 +-
 .../AST/Styling/Options/ListItemOptions.swift   |  2 +-
 .../Styling/Options/QuoteStripeOptions.swift    |  4 ++++
 .../Styling/Options/ThematicBreakOptions.swift  |  2 +-
 Source/AST/Styling/Stylers/DownStyler.swift     |  2 +-
 .../Stylers/DownStylerConfiguration.swift       |  2 +-
 .../Styling/Text Views/DownDebugTextView.swift  |  2 +-
 .../AST/Styling/Text Views/DownTextView.swift   |  2 +-
 .../AST/Visitors/AttributedStringVisitor.swift  |  3 +++
 Source/Down.swift                               |  7 +++++--
 Source/Extensions/NSAttributedString+HTML.swift |  3 +++
 .../DownAttributedStringRenderable.swift        |  2 ++
 Source/Views/DownView.swift                     |  2 ++
 docker/Dockerfile                               |  6 ++++++
 docker/README.md                                |  6 ++++++
 docker/docker-compose.yml                       | 12 ++++++++++++
 docker/down-rebuild.sh                          | 17 +++++++++++++++++
 30 files changed, 92 insertions(+), 19 deletions(-)
 create mode 100644 LinuxMain.swift
 create mode 100644 docker/Dockerfile
 create mode 100644 docker/README.md
 create mode 100644 docker/docker-compose.yml
 create mode 100755 docker/down-rebuild.sh

diff --git a/LinuxMain.swift b/LinuxMain.swift
new file mode 100644
index 0000000..b45b7af
--- /dev/null
+++ b/LinuxMain.swift
@@ -0,0 +1,7 @@
+import XCTest
+
+var tests = [XCTestCaseEntry]()
+
+// FIXME: Run on macOS `swift test --generate-linuxmain` and maintain Linux Tests.
+
+XCTMain(tests)
diff --git a/Source/AST/Styling/Attribute Collections/ColorCollection.swift b/Source/AST/Styling/Attribute Collections/ColorCollection.swift
index 25b0093..0ed19ff 100644
--- a/Source/AST/Styling/Attribute Collections/ColorCollection.swift	
+++ b/Source/AST/Styling/Attribute Collections/ColorCollection.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Attribute Collections/FontCollection.swift b/Source/AST/Styling/Attribute Collections/FontCollection.swift
index ff78724..10ff93c 100644
--- a/Source/AST/Styling/Attribute Collections/FontCollection.swift	
+++ b/Source/AST/Styling/Attribute Collections/FontCollection.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Attribute Collections/ParagraphStyleCollection.swift b/Source/AST/Styling/Attribute Collections/ParagraphStyleCollection.swift
index 70da7f2..fb4b989 100644
--- a/Source/AST/Styling/Attribute Collections/ParagraphStyleCollection.swift	
+++ b/Source/AST/Styling/Attribute Collections/ParagraphStyleCollection.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Custom Attributes/BlockBackgroundColorAttribute.swift b/Source/AST/Styling/Custom Attributes/BlockBackgroundColorAttribute.swift
index 391c5a0..d5ff2f7 100644
--- a/Source/AST/Styling/Custom Attributes/BlockBackgroundColorAttribute.swift	
+++ b/Source/AST/Styling/Custom Attributes/BlockBackgroundColorAttribute.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Custom Attributes/QuoteStripeAttribute.swift b/Source/AST/Styling/Custom Attributes/QuoteStripeAttribute.swift
index e97e9d2..e2b2ca2 100644
--- a/Source/AST/Styling/Custom Attributes/QuoteStripeAttribute.swift	
+++ b/Source/AST/Styling/Custom Attributes/QuoteStripeAttribute.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Custom Attributes/ThematicBreakAttribute.swift b/Source/AST/Styling/Custom Attributes/ThematicBreakAttribute.swift
index d199a59..2c280d6 100644
--- a/Source/AST/Styling/Custom Attributes/ThematicBreakAttribute.swift	
+++ b/Source/AST/Styling/Custom Attributes/ThematicBreakAttribute.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Helpers/Extensions/CGPoint+Translate.swift b/Source/AST/Styling/Helpers/Extensions/CGPoint+Translate.swift
index 9c224f8..2ecb5a0 100644
--- a/Source/AST/Styling/Helpers/Extensions/CGPoint+Translate.swift
+++ b/Source/AST/Styling/Helpers/Extensions/CGPoint+Translate.swift
@@ -6,6 +6,8 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
+#if !os(Linux)
+
 #if canImport(UIKit)
 
 import UIKit
@@ -22,3 +24,5 @@ extension CGPoint {
         return CGPoint(x: x + point.x, y: y + point.y)
     }
 }
+
+#endif
diff --git a/Source/AST/Styling/Helpers/Extensions/CGRect+Helpers.swift b/Source/AST/Styling/Helpers/Extensions/CGRect+Helpers.swift
index 89adaac..57b2f2c 100644
--- a/Source/AST/Styling/Helpers/Extensions/CGRect+Helpers.swift
+++ b/Source/AST/Styling/Helpers/Extensions/CGRect+Helpers.swift
@@ -6,6 +6,8 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
+#if !os(Linux)
+
 #if canImport(UIKit)
 
 import UIKit
@@ -26,3 +28,5 @@ extension CGRect {
         return CGRect(origin: origin.translated(by: point), size: size)
     }
 }
+
+#endif
diff --git a/Source/AST/Styling/Helpers/Extensions/UIFont+Traits.swift b/Source/AST/Styling/Helpers/Extensions/UIFont+Traits.swift
index a94af1f..72dc056 100644
--- a/Source/AST/Styling/Helpers/Extensions/UIFont+Traits.swift
+++ b/Source/AST/Styling/Helpers/Extensions/UIFont+Traits.swift
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Helpers/ListItemParagraphStyler.swift b/Source/AST/Styling/Helpers/ListItemParagraphStyler.swift
index 90b54ec..f010775 100644
--- a/Source/AST/Styling/Helpers/ListItemParagraphStyler.swift
+++ b/Source/AST/Styling/Helpers/ListItemParagraphStyler.swift
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Layout Managers/DownDebugLayoutManager.swift b/Source/AST/Styling/Layout Managers/DownDebugLayoutManager.swift
index 997f09c..e96835d 100644
--- a/Source/AST/Styling/Layout Managers/DownDebugLayoutManager.swift	
+++ b/Source/AST/Styling/Layout Managers/DownDebugLayoutManager.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Layout Managers/DownLayoutManager.swift b/Source/AST/Styling/Layout Managers/DownLayoutManager.swift
index a717047..dea1078 100644
--- a/Source/AST/Styling/Layout Managers/DownLayoutManager.swift	
+++ b/Source/AST/Styling/Layout Managers/DownLayoutManager.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Options/CodeBlockOptions.swift b/Source/AST/Styling/Options/CodeBlockOptions.swift
index 10a041e..9b19142 100644
--- a/Source/AST/Styling/Options/CodeBlockOptions.swift
+++ b/Source/AST/Styling/Options/CodeBlockOptions.swift
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Options/ListItemOptions.swift b/Source/AST/Styling/Options/ListItemOptions.swift
index 244cf61..765f18f 100644
--- a/Source/AST/Styling/Options/ListItemOptions.swift
+++ b/Source/AST/Styling/Options/ListItemOptions.swift
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Options/QuoteStripeOptions.swift b/Source/AST/Styling/Options/QuoteStripeOptions.swift
index f5439b7..f70525e 100644
--- a/Source/AST/Styling/Options/QuoteStripeOptions.swift
+++ b/Source/AST/Styling/Options/QuoteStripeOptions.swift
@@ -6,6 +6,8 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
+#if !os(Linux)
+
 #if canImport(UIKit)
 
 import UIKit
@@ -21,3 +23,5 @@ public struct QuoteStripeOptions {
     public var thickness: CGFloat = 2
     public var spacingAfter: CGFloat = 8
 }
+
+#endif
diff --git a/Source/AST/Styling/Options/ThematicBreakOptions.swift b/Source/AST/Styling/Options/ThematicBreakOptions.swift
index e44e05e..873f72e 100644
--- a/Source/AST/Styling/Options/ThematicBreakOptions.swift
+++ b/Source/AST/Styling/Options/ThematicBreakOptions.swift
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Stylers/DownStyler.swift b/Source/AST/Styling/Stylers/DownStyler.swift
index 6622132..5f669a3 100644
--- a/Source/AST/Styling/Stylers/DownStyler.swift
+++ b/Source/AST/Styling/Stylers/DownStyler.swift
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Stylers/DownStylerConfiguration.swift b/Source/AST/Styling/Stylers/DownStylerConfiguration.swift
index 0e8ee20..ebb7355 100644
--- a/Source/AST/Styling/Stylers/DownStylerConfiguration.swift
+++ b/Source/AST/Styling/Stylers/DownStylerConfiguration.swift
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 /// A configuration object used to initialze the `DownStyler`.
 public struct DownStylerConfiguration {
diff --git a/Source/AST/Styling/Text Views/DownDebugTextView.swift b/Source/AST/Styling/Text Views/DownDebugTextView.swift
index 995f236..8c97b64 100644
--- a/Source/AST/Styling/Text Views/DownDebugTextView.swift	
+++ b/Source/AST/Styling/Text Views/DownDebugTextView.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Styling/Text Views/DownTextView.swift b/Source/AST/Styling/Text Views/DownTextView.swift
index cb0191c..98982e9 100644
--- a/Source/AST/Styling/Text Views/DownTextView.swift	
+++ b/Source/AST/Styling/Text Views/DownTextView.swift	
@@ -6,7 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
-#if !os(watchOS)
+#if !os(watchOS) && !os(Linux)
 
 #if canImport(UIKit)
 
diff --git a/Source/AST/Visitors/AttributedStringVisitor.swift b/Source/AST/Visitors/AttributedStringVisitor.swift
index 0a48916..5134e0a 100644
--- a/Source/AST/Visitors/AttributedStringVisitor.swift
+++ b/Source/AST/Visitors/AttributedStringVisitor.swift
@@ -5,6 +5,8 @@
 //  Created by John Nguyen on 09.04.19.
 //
 
+#if !os(Linux)
+
 import Foundation
 
 /// This class is used to generated an `NSMutableAttributedString` from the abstract syntax
@@ -221,3 +223,4 @@ private extension String {
         return lines.joined(separator: .lineSeparator)
     }
 }
+#endif // !os(Linux)
diff --git a/Source/Down.swift b/Source/Down.swift
index 4746bdb..22d695e 100644
--- a/Source/Down.swift
+++ b/Source/Down.swift
@@ -9,8 +9,7 @@
 import Foundation
 
 public struct Down: DownASTRenderable, DownHTMLRenderable, DownXMLRenderable,
-                    DownLaTeXRenderable, DownGroffRenderable, DownCommonMarkRenderable,
-                    DownAttributedStringRenderable {
+                    DownLaTeXRenderable, DownGroffRenderable, DownCommonMarkRenderable {
     /// A string containing CommonMark Markdown
     public var markdownString: String
 
@@ -21,3 +20,7 @@ public struct Down: DownASTRenderable, DownHTMLRenderable, DownXMLRenderable,
         self.markdownString = markdownString
     }
 }
+
+#if !os(Linux)
+extension Down: DownAttributedStringRenderable { }
+#endif // !os(Linux)
diff --git a/Source/Extensions/NSAttributedString+HTML.swift b/Source/Extensions/NSAttributedString+HTML.swift
index e9e74a6..c480757 100644
--- a/Source/Extensions/NSAttributedString+HTML.swift
+++ b/Source/Extensions/NSAttributedString+HTML.swift
@@ -6,6 +6,8 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
+#if !os(Linux)
+
 #if os(macOS)
     import AppKit
 #else
@@ -32,3 +34,4 @@ extension NSAttributedString {
     }
 
 }
+#endif // !os(Linux)
diff --git a/Source/Renderers/DownAttributedStringRenderable.swift b/Source/Renderers/DownAttributedStringRenderable.swift
index 76e00ce..c274712 100644
--- a/Source/Renderers/DownAttributedStringRenderable.swift
+++ b/Source/Renderers/DownAttributedStringRenderable.swift
@@ -6,6 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
+#if !os(Linux)
 import Foundation
 import libcmark
 
@@ -56,3 +57,4 @@ extension DownAttributedStringRenderable {
         return document.accept(visitor)
     }
 }
+#endif // !os(Linux)
diff --git a/Source/Views/DownView.swift b/Source/Views/DownView.swift
index 840e5c1..4b95eef 100644
--- a/Source/Views/DownView.swift
+++ b/Source/Views/DownView.swift
@@ -6,6 +6,7 @@
 //  Copyright © 2016-2019 Down. All rights reserved.
 //
 
+#if !os(Linux)
 #if os(tvOS) || os(watchOS)
     // Sorry, not available for tvOS nor watchOS
 #else
@@ -205,3 +206,4 @@ private extension WKNavigationDelegate {
 }
 
 #endif
+#endif // !os(Linux)
diff --git a/docker/Dockerfile b/docker/Dockerfile
new file mode 100644
index 0000000..b91e39e
--- /dev/null
+++ b/docker/Dockerfile
@@ -0,0 +1,6 @@
+# You can set the Swift version to what you need for your app. Versions can be found here: https://hub.docker.com/_/swift
+FROM swift:5.1
+
+RUN apt-get -qq update \
+  && apt-get -q -y install libssl-dev zlib1g-dev \
+  && rm -r /var/lib/apt/lists/*
diff --git a/docker/README.md b/docker/README.md
new file mode 100644
index 0000000..b0abcf6
--- /dev/null
+++ b/docker/README.md
@@ -0,0 +1,6 @@
+# Building on Linux (Docker)
+
+- Go to "docker" directory: `cd $REPO/docker`
+- Compose docket image: `docker-compose build`.
+- Build sources: `docker-compose run --rm down`.
+- Login docker image (i.e. to troubleshoot build failures): `docker-compose run --rm down bash`. After that you can run `swift build --package-path /app` or `cd /app && swift build`.
diff --git a/docker/docker-compose.yml b/docker/docker-compose.yml
new file mode 100644
index 0000000..0e632c3
--- /dev/null
+++ b/docker/docker-compose.yml
@@ -0,0 +1,12 @@
+version: "3.3"
+services:
+  down:
+    build:
+      context: .
+      dockerfile: Dockerfile
+    volumes:
+      - ../:/app
+    working_dir: /app
+    stdin_open: true
+    tty: true
+    command: /app/docker/down-rebuild.sh
diff --git a/docker/down-rebuild.sh b/docker/down-rebuild.sh
new file mode 100755
index 0000000..a632316
--- /dev/null
+++ b/docker/down-rebuild.sh
@@ -0,0 +1,17 @@
+#!/bin/bash
+
+echo "- Cleaning App"
+swift package clean
+if [ $? != 0 ]; then
+  echo "❌ Linux build failed."
+  exit 1
+fi
+
+echo "- Building App"
+swift build --configuration release
+if [ $? != 0 ]; then
+  echo "❌ Linux build failed."
+  exit 1
+fi
+
+echo "✅ Linux build completed!"