[SyntaxColoring] Tolerating empty spaces between doc-comment openning… (#3373)

* [SyntaxColoring] Tolerating empty spaces between doc-comment opennings and field keywords. rdar://26310081

* [test] Update test for SourceKit.

Author: nkcsgexi

lib/IDE/SyntaxModel.cpp

@@ -245,7 +245,7 @@ static const char *const RegexStrURL =
 #define MARKUP_SIMPLE_FIELD(Id, Keyword, XMLKind) \
   #Keyword "|"
 static const char *const RegexStrDocCommentField =
-  "^[ ]?- ("
+  "^[ ]*- ("
 #include "swift/Markup/SimpleFields.def"
   "returns):";
 

test/IDE/coloring.swift

@@ -168,6 +168,18 @@ func foo(n: Float) -> Int {
     return 100009
 }
 
+///- returns: single-line, no space
+// CHECK: ///- <doc-comment-field>returns</doc-comment-field>: single-line, no space
+
+/// - returns: single-line, 1 space
+// CHECK: /// - <doc-comment-field>returns</doc-comment-field>: single-line, 1 space
+
+///  - returns: single-line, 2 spaces
+// CHECK: ///  - <doc-comment-field>returns</doc-comment-field>: single-line, 2 spaces
+
+///       - returns: single-line, more spaces
+// CHECK: ///       - <doc-comment-field>returns</doc-comment-field>: single-line, more spaces
+
 // CHECK: <kw>protocol</kw> Prot {
 protocol Prot {
   // CHECK: <kw>typealias</kw> Blarg

test/SourceKit/SyntaxMapData/syntaxmap.swift.response

@@ -361,7 +361,17 @@
     {
       key.kind: source.lang.swift.syntaxtype.doccomment,
       key.offset: 666,
-      key.length: 59
+      key.length: 13
+    },
+    {
+      key.kind: source.lang.swift.syntaxtype.doccomment.field,
+      key.offset: 679,
+      key.length: 8
+    },
+    {
+      key.kind: source.lang.swift.syntaxtype.doccomment,
+      key.offset: 687,
+      key.length: 38
     },
     {
       key.kind: source.lang.swift.syntaxtype.keyword,