Changeset 99513 in webkit for trunk/Source/JavaScriptCore/parser/Parser.cpp

Timestamp:

Nov 7, 2011, 6:25:20 PM (14 years ago)

Author:

[email protected]

Message:

"use strict" can not contain escape sequences or line continuation
​https://bugs.webkit.org/show_bug.cgi?id=71532

Reviewed by Darin Adler.

Source/JavaScriptCore:

Store the actual literal length (before the escapes and line
continuation are encoded) while parsing the directive and use it
for the directive comparison.

• parser/Parser.cpp:

(JSC::Parser::parseSourceElements):
(JSC::Parser::parseStatement):

• parser/Parser.h:

LayoutTests:

• fast/js/basic-strict-mode-expected.txt:
• fast/js/script-tests/basic-strict-mode.js:

(testLineContinuation): Added.
(testEscapeSequence): Added.

File:

• trunk/Source/JavaScriptCore/parser/Parser.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/parser/Parser.cpp

@@ -130 +130 @@
 template <Parser::SourceElementsMode mode, class TreeBuilder> TreeSourceElements Parser::parseSourceElements(TreeBuilder& context)
 {
+    const unsigned lengthOfUseStrictLiteral = 12; // "use strict".length
     TreeSourceElements sourceElements = context.createSourceElements();
     bool seenNonDirective = false;
     const Identifier* directive = 0;
+    unsigned directiveLiteralLength = 0;
     unsigned startOffset = m_token.m_info.startOffset;
     unsigned oldLastLineNumber = m_lexer->lastLineNumber();
     unsigned oldLineNumber = m_lexer->lineNumber();
     bool hasSetStrict = false;
-    while (TreeStatement statement = parseStatement(context, directive)) {
+    while (TreeStatement statement = parseStatement(context, directive, &directiveLiteralLength)) {
         if (mode == CheckForStrictMode && !seenNonDirective) {
             if (directive) {
-                if (!hasSetStrict && m_globalData->propertyNames->useStrictIdentifier == *directive) {
+                // "use strict" must be the exact literal without escape sequences or line continuation.
+                if (!hasSetStrict && directiveLiteralLength == lengthOfUseStrictLiteral && m_globalData->propertyNames->useStrictIdentifier == *directive) {
                     setStrictMode();
                     hasSetStrict = true;
@@ -649 +652 @@
 }
 
-template <class TreeBuilder> TreeStatement Parser::parseStatement(TreeBuilder& context, const Identifier*& directive)
+template <class TreeBuilder> TreeStatement Parser::parseStatement(TreeBuilder& context, const Identifier*& directive, unsigned* directiveLiteralLength)
 {
     DepthManager statementDepth(&m_statementDepth);
@@ -703 +706 @@
     case STRING:
         directive = m_token.m_data.ident;
+        if (directiveLiteralLength)
+            *directiveLiteralLength = m_token.m_info.endOffset - m_token.m_info.startOffset;
         nonTrivialExpressionCount = m_nonTrivialExpressionCount;
     default: