Bug 1384463 - only trim CSS-allowed whitespace in declaration parser; r=gl

MozReview-Commit-ID: 7bnu2a9G1uq

--HG--
extra : rebase_source : 32fc701fe10f44e36c88aa73d4b234b94f9990f1

devtools/client/shared/test/unit/test_parseDeclarations.js

@@ -365,6 +365,15 @@ const TEST_DATA = [
     input: "stroke-dasharray: 1/*ThisIsAComment*/2;",
     expected: [{name: "stroke-dasharray", value: "1 2", priority: "", offsets: [0, 39]}]
   },
+
+  // Regression test for bug 1384463 - don't trim significant
+  // whitespace.
+  {
+    // \u00a0 is non-breaking space.
+    input: "\u00a0vertical-align: top",
+    expected: [{name: "\u00a0vertical-align", value: "top", priority: "",
+                offsets: [0, 20]}]
+  },
 ];
 
 function run_test() {

devtools/shared/css/parsing-utils.js

@@ -249,6 +249,28 @@ function getEmptyDeclaration() {
           colonOffsets: false};
 }
 
+/**
+ * Like trim, but only trims CSS-allowed whitespace.
+ */
+function cssTrim(str) {
+  let match = /^[ \t\r\n\f]*(.*?)[ \t\r\n\f]*$/.exec(str);
+  if (match) {
+    return match[1];
+  }
+  return str;
+}
+
+/**
+ * Like trimRight, but only trims CSS-allowed whitespace.
+ */
+function cssTrimRight(str) {
+  let match = /^(.*?)[ \t\r\n\f]*$/.exec(str);
+  if (match) {
+    return match[1];
+  }
+  return str;
+}
+
 /**
  * A helper function that does all the parsing work for
  * parseDeclarations.  This is separate because it has some arguments
@@ -310,7 +332,7 @@ function parseDeclarationsInternal(isCssPropertyKnown, inputString,
     if (token.tokenType === "symbol" && token.text === ":") {
       if (!lastProp.name) {
         // Set the current declaration name if there's no name yet
-        lastProp.name = current.trim();
+        lastProp.name = cssTrim(current);
         lastProp.colonOffsets = [token.startOffset, token.endOffset];
         current = "";
         hasBang = false;
@@ -336,7 +358,7 @@ function parseDeclarationsInternal(isCssPropertyKnown, inputString,
         current = "";
         break;
       }
-      lastProp.value = current.trim();
+      lastProp.value = cssTrim(current);
       current = "";
       hasBang = false;
       declarations.push(getEmptyDeclaration());
@@ -384,11 +406,11 @@ function parseDeclarationsInternal(isCssPropertyKnown, inputString,
       // Ignore this case in comments.
       if (!inComment) {
         // Trailing property found, e.g. p1:v1;p2:v2;p3
-        lastProp.name = current.trim();
+        lastProp.name = cssTrim(current);
       }
     } else {
       // Trailing value found, i.e. value without an ending ;
-      lastProp.value = current.trim();
+      lastProp.value = cssTrim(current);
       let terminator = lexer.performEOFFixup("", true);
       lastProp.terminator = terminator + ";";
       // If the input was unterminated, attribute the remainder to
@@ -833,7 +855,7 @@ RuleRewriter.prototype = {
       // a property but which would break the entire style sheet.
       let newText = this.inputString.substring(decl.colonOffsets[1],
                                                decl.offsets[1]);
-      newText = unescapeCSSComment(newText).trimRight();
+      newText = cssTrimRight(unescapeCSSComment(newText));
       this.result += this.sanitizeText(newText, index) + ";";
 
       // See if the comment end can be deleted.