Make RegExp character class match JSC.

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index fd93aae4241d7494dc26522ca4904081e746c4eb..94ad57c9c28ba02a40b111562c56aa1f243129b1 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -4449,6 +4449,22 @@ CharacterRange RegExpParser::ParseClassAtom(uc16* char_class) {
 }
 
 
+static const uc16 kNoCharClass = 0;
+
+// Adds range or pre-defined character class to character ranges.
+// If char_class is not kInvalidClass, it's interpreted as a class
+// escape (i.e., 's' means whitespace, from '\s').
+static inline void AddRangeOrEscape(ZoneList<CharacterRange>* ranges,
+                                    uc16 char_class,
+                                    CharacterRange range) {
+  if (char_class != kNoCharClass) {
+    CharacterRange::AddClassEscape(char_class, ranges);
+  } else {
+    ranges->Add(range);
+  }
+}
+
+
 RegExpTree* RegExpParser::ParseCharacterClass() {
   static const char* kUnterminated = "Unterminated character class";
   static const char* kRangeOutOfOrder = "Range out of order in character class";
@@ -4462,12 +4478,8 @@ RegExpTree* RegExpParser::ParseCharacterClass() {
   }
   ZoneList<CharacterRange>* ranges = new ZoneList<CharacterRange>(2);
   while (has_more() && current() != ']') {
-    uc16 char_class = 0;
+    uc16 char_class = kNoCharClass;
     CharacterRange first = ParseClassAtom(&char_class CHECK_FAILED);
-    if (char_class) {
-      CharacterRange::AddClassEscape(char_class, ranges);
-      continue;
-    }
     if (current() == '-') {
       Advance();
       if (current() == kEndMarker) {
@@ -4475,15 +4487,17 @@ RegExpTree* RegExpParser::ParseCharacterClass() {
         // following code report an error.
         break;
       } else if (current() == ']') {
-        ranges->Add(first);
+        AddRangeOrEscape(ranges, char_class, first);
         ranges->Add(CharacterRange::Singleton('-'));
         break;
       }
-      CharacterRange next = ParseClassAtom(&char_class CHECK_FAILED);
-      if (char_class) {
-        ranges->Add(first);
+      uc16 char_class_2 = kNoCharClass;
+      CharacterRange next = ParseClassAtom(&char_class_2 CHECK_FAILED);
+      if (char_class != kNoCharClass || char_class_2 != kNoCharClass) {
+        // Either end is an escaped character class. Treat the '-' verbatim.
+        AddRangeOrEscape(ranges, char_class, first);
         ranges->Add(CharacterRange::Singleton('-'));
-        CharacterRange::AddClassEscape(char_class, ranges);
+        AddRangeOrEscape(ranges, char_class_2, next);
         continue;
       }
       if (first.from() > next.to()) {
@@ -4491,7 +4505,7 @@ RegExpTree* RegExpParser::ParseCharacterClass() {
       }
       ranges->Add(CharacterRange::Range(first.from(), next.to()));
     } else {
-      ranges->Add(first);
+      AddRangeOrEscape(ranges, char_class, first);
     }
   }
   if (!has_more()) {