Fix issue where extensions would pick up documentation from previous tokens

CHANGELOG.md

@@ -16,6 +16,11 @@ None.
   [JP Simard](https://github.com/jpsim)
   [jazzy#374](https://github.com/realm/jazzy/issues/374)
 
+* Fix issue where Swift extensions would pick up documentation from previous
+  tokens.  
+  [JP Simard](https://github.com/jpsim)
+  [#65](https://github.com/jpsim/SourceKitten/issues/65)
+
 
 ## 0.6.1
 

Source/SourceKittenFramework/File.swift

@@ -309,6 +309,11 @@ public struct File {
     public func getDocumentationCommentBody(dictionary: XPCDictionary, syntaxMap: SyntaxMap) -> String? {
         return SwiftDocKey.getOffset(dictionary).flatMap { offset in
             return syntaxMap.commentRangeBeforeOffset(Int(offset)).flatMap { commentByteRange in
+                let commentEndLine = (contents as NSString).lineAndCharacterForCharacterOffset(commentByteRange.endIndex)?.line
+                let tokenStartLine = (contents as NSString).lineAndCharacterForCharacterOffset(Int(offset))?.line
+                guard commentEndLine == tokenStartLine else {
+                    return nil
+                }
                 return contents.byteRangeToNSRange(start: commentByteRange.startIndex, length: commentByteRange.endIndex - commentByteRange.startIndex).flatMap { nsRange in
                     return contents.commentBody(nsRange)
                 }

Source/SourceKittenFramework/String+SourceKitten.swift

@@ -57,6 +57,21 @@ extension NSString {
         return nil
     }
 
+    public func lineAndCharacterForCharacterOffset(offset: Int) -> (line: Int, character: Int)? {
+        let range = NSRange(location: offset, length: 0)
+        var numberOfLines = 0, index = 0, lineRangeStart = 0, previousIndex = 0
+        while index < length {
+            numberOfLines++
+            if index > range.location {
+                break
+            }
+            lineRangeStart = numberOfLines
+            previousIndex = index
+            index = NSMaxRange(lineRangeForRange(NSRange(location: index, length: 1)))
+        }
+        return (lineRangeStart, range.location - previousIndex + 1)
+    }
+
     /**
     Returns a copy of `self` with the trailing contiguous characters belonging to `characterSet`
     removed.

Source/SourceKittenFramework/SyntaxKind.swift

@@ -48,12 +48,8 @@ public enum SyntaxKind: String {
     /// `typeidentifier`.
     case Typeidentifier = "source.lang.swift.syntaxtype.typeidentifier"
 
-    /**
-    Returns true if the input is a comment-like syntax kind string.
-
-    - parameter string: Input string.
-    */
-    internal static func isCommentLike(string: Swift.String) -> Bool {
-        return [Comment, CommentMark, CommentURL, DocComment, DocCommentField].map({ $0.rawValue }).contains(string)
+    /// Returns the valid documentation comment syntax kinds.
+    internal static func docComments() -> [SyntaxKind] {
+        return [CommentURL, DocComment, DocCommentField]
     }
 }

Source/SourceKittenFramework/SyntaxMap.swift

@@ -73,8 +73,8 @@ public struct SyntaxMap {
     */
     public func commentRangeBeforeOffset(offset: Int) -> Range<Int>? {
         let tokensBeforeOffset = tokens.filter { $0.offset < offset }
-        let commentTokensImmediatelyPrecedingOffset = filterLastContiguous(tokensBeforeOffset) {
-            SyntaxKind.isCommentLike($0.type)
+        let commentTokensImmediatelyPrecedingOffset = filterLastContiguous(tokensBeforeOffset) { token in
+            SyntaxKind.docComments().map({$0.rawValue}).contains(token.type)
         }
         return commentTokensImmediatelyPrecedingOffset.first.flatMap { firstToken in
             return commentTokensImmediatelyPrecedingOffset.last.map { lastToken in

Source/SourceKittenFrameworkTests/Fixtures/Commandant.json

@@ -730,7 +730,6 @@
       {
         "key.kind" : "source.lang.swift.decl.extension",
         "key.offset" : 3535,
-        "key.doc.comment" : "Attempts to parse a value from the given command-line argument.",
         "key.namelength" : 3,
         "key.bodyoffset" : 3564,
         "key.bodylength" : 119,
@@ -811,7 +810,6 @@
       {
         "key.kind" : "source.lang.swift.decl.extension",
         "key.offset" : 3686,
-        "key.doc.comment" : "Attempts to parse a value from the given command-line argument.",
         "key.modulename" : "Swift",
         "key.namelength" : 6,
         "key.bodyoffset" : 3718,