Bug 751939 - make url( followed by EOF valid. r=dbaron

layout/style/nsCSSParser.cpp

@@ -3355,7 +3355,8 @@ CSSParserImpl::ParseMozDocumentRule(RuleAppendFunc aAppendFunc, void* aData)
       }
 
       NS_ASSERTION(!mHavePushBack, "mustn't have pushback at this point");
-      if (!mScanner->NextURL(mToken) || mToken.mType != eCSSToken_URL) {
+      mScanner->NextURL(mToken);
+      if (mToken.mType != eCSSToken_URL) {
         REPORT_UNEXPECTED_TOKEN(PEMozDocRuleNotURI);
         SkipUntil(')');
         delete urls;

layout/style/nsCSSScanner.cpp

@@ -1149,25 +1149,21 @@ nsCSSScanner::AppendImpliedEOFCharacters(EOFCharacters aEOFCharacters,
  * Exposed for use by nsCSSParser::ParseMozDocumentRule, which applies
  * the special lexical rules for URL tokens in a nonstandard context.
  */
-bool
+void
 nsCSSScanner::NextURL(nsCSSToken& aToken)
 {
   SkipWhitespace();
 
-  int32_t ch = Peek();
-  if (ch < 0) {
-    return false;
-  }
-
   // aToken.mIdent may be "url" at this point; clear that out
   aToken.mIdent.Truncate();
 
+  int32_t ch = Peek();
   // Do we have a string?
   if (ch == '"' || ch == '\'') {
     ScanString(aToken);
     if (MOZ_UNLIKELY(aToken.mType == eCSSToken_Bad_String)) {
       aToken.mType = eCSSToken_Bad_URL;
-      return true;
+      return;
     }
     MOZ_ASSERT(aToken.mType == eCSSToken_String, "unexpected token type");
 
@@ -1180,6 +1176,7 @@ nsCSSScanner::NextURL(nsCSSToken& aToken)
   // Consume trailing whitespace and then look for a close parenthesis.
   SkipWhitespace();
   ch = Peek();
+  // ch can be less than zero indicating EOF
   if (MOZ_LIKELY(ch < 0 || ch == ')')) {
     Advance();
     aToken.mType = eCSSToken_URL;
@@ -1190,7 +1187,6 @@ nsCSSScanner::NextURL(nsCSSToken& aToken)
     mSeenBadToken = true;
     aToken.mType = eCSSToken_Bad_URL;
   }
-  return true;
 }
 
 /**

layout/style/nsCSSScanner.h

@@ -234,7 +234,7 @@ class nsCSSScanner {
   // which, for historical reasons, must make additional function
   // tokens behave like url().  Please do not add new uses to the
   // parser.
-  bool NextURL(nsCSSToken& aTokenResult);
+  void NextURL(nsCSSToken& aTokenResult);
 
   // This is exposed for use by nsCSSParser::ParsePseudoClassWithNthPairArg,
   // because "2n-1" is a single DIMENSION token, and "n-1" is a single

layout/style/test/test_css_eof_handling.html

@@ -87,6 +87,12 @@ const tests = [
            "wHCBYQNDAQAMuALRrGb97AAAAABJRU5ErkJggg=='",
       prop: "background-image", pseudo: ""
   },
+  {
+      name: "url-token 4",	/*Bug 751939*/
+      ref: "#r { background-image: url( )}",
+      tst: "#t { background-image: url(" ,
+      prop: "background-image", pseudo: ""
+  },
   {
       name: "counter",
       ref: "#r::before { content: counter(tr, upper-alpha) }",