From a2a636d7498d2ed245cc7e91c6b41aecdeee7b9d Mon Sep 17 00:00:00 2001
From: JP Simard <jp@jpsim.com>
Date: Wed, 23 Nov 2016 15:30:29 -0800
Subject: [PATCH] fix MarkRule edge cases

fixes #805
---
 CHANGELOG.md                                  |  5 +++-
 .../SwiftLintFramework/Rules/MarkRule.swift   | 25 ++++++++++++++-----
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ef4fd4344..631cefbe3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,7 +10,10 @@
 
 ##### Bug Fixes
 
-* None.
+* Fix a few edge cases where malformed `MARK:` comments wouldn't trigger a
+  violation.  
+  [JP Simard](https://github.com/jpsim)
+  [#805](https://github.com/realm/SwiftLint/issues/805)
 
 ## 0.13.0: MakeYourClothesCleanAgain
 
diff --git a/Source/SwiftLintFramework/Rules/MarkRule.swift b/Source/SwiftLintFramework/Rules/MarkRule.swift
index 52099894d..77a1afa60 100644
--- a/Source/SwiftLintFramework/Rules/MarkRule.swift
+++ b/Source/SwiftLintFramework/Rules/MarkRule.swift
@@ -19,22 +19,35 @@ public struct MarkRule: ConfigurationProviderRule {
         name: "Mark",
         description: "MARK comment should be in valid format.",
         nonTriggeringExamples: [
-            "// MARK: good\n",
-            "// MARK: - good\n",
-            "// MARK: -\n"
+            "// MARK: good",
+            "// MARK: - good",
+            "// MARK: -"
         ],
         triggeringExamples: [
             "//MARK: bad",
+            "// MARK:bad",
             "//MARK:bad",
+            "//  MARK: bad",
+            "// MARK:  bad",
             "// MARK: -bad",
+            "// MARK:- bad",
             "// MARK:-bad",
-            "//MARK:-bad"
+            "//MARK: - bad",
+            "//MARK:- bad",
+            "//MARK: -bad",
+            "//MARK:-bad",
         ]
     )
 
     public func validateFile(file: File) -> [StyleViolation] {
-        let options = ["MARK:[^ ]", "[^ ]MARK: [^-]", "\\sMARK:[^ ]", "MARK:[ ][-][^\\s ]"]
-        let pattern = "(" + options.joinWithSeparator("|") + ")"
+        let nonSpace = "[^ ]"
+        let twoOrMoreSpace = " {2,}"
+        let nonSpaceOrTwoOrMoreSpace = "(\(nonSpace)|\(twoOrMoreSpace))"
+        let mark = "MARK:"
+        let badSpaceStart = "(\(nonSpaceOrTwoOrMoreSpace)?\(mark)\(nonSpaceOrTwoOrMoreSpace))"
+        let badSpaceEnd = "(\(nonSpaceOrTwoOrMoreSpace)\(mark)\(nonSpaceOrTwoOrMoreSpace)?)"
+        let badSpaceAfterHyphen = "(\(mark) -([^ \\n]|\(twoOrMoreSpace)))"
+        let pattern = [badSpaceStart, badSpaceEnd, badSpaceAfterHyphen].joinWithSeparator("|")
 
         return file.matchPattern(pattern, withSyntaxKinds: [.Comment]).flatMap { range in
             return StyleViolation(ruleDescription: self.dynamicType.description,