Changeset 211319 in webkit for trunk/Source/JavaScriptCore/runtime/TemplateRegistry.cpp

Timestamp:

Jan 27, 2017, 7:09:12 PM (8 years ago)

Author:

Yusuke Suzuki

Message:

Lift template escape sequence restrictions in tagged templates
​https://bugs.webkit.org/show_bug.cgi?id=166871

Reviewed by Saam Barati.

JSTests:

Update the error messages and add new tests.

• ChakraCore/test/es6/unicode_6_identifier_Blue524737.baseline-jsc:
• stress/lift-template-literal.js: Added.

(dump):
(testTag.return.tag):
(testTag):

• stress/template-literal-syntax.js:

Source/JavaScriptCore:

This patch implements stage 3 Lifting Template Literal Restriction[1].
Prior to this patch, template literal becomes syntax error if it contains
invalid escape sequences. But it is too restricted; Template literal
can have cooked and raw representations and only cooked representation
can escape sequences. So even if invalid escape sequences are included,
the raw representation can be valid.

Lifting Template Literal Restriction relaxes the above restriction.
When invalid escape sequence is included, if target template literals
are used as tagged templates, we make the result of the template including
the invalid escape sequence undefined instead of making it SyntaxError
immediately. It allows us to accept the templates including invalid
escape sequences in the raw representations in tagged templates.

On the other hand, the raw representation is only used in tagged templates.
So if invalid escape sequences are included in the usual template literals,
we just make it SyntaxError as before.

[1]: ​https://github.com/tc39/proposal-template-literal-revision

• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::emitGetTemplateObject):

• bytecompiler/NodesCodegen.cpp:

(JSC::TemplateStringNode::emitBytecode):
(JSC::TemplateLiteralNode::emitBytecode):

• parser/ASTBuilder.h:

(JSC::ASTBuilder::createTemplateString):

• parser/Lexer.cpp:

(JSC::Lexer<CharacterType>::parseUnicodeEscape):
(JSC::Lexer<T>::parseTemplateLiteral):
(JSC::Lexer<T>::lex):
(JSC::Lexer<T>::scanTemplateString):
(JSC::Lexer<T>::scanTrailingTemplateString): Deleted.

• parser/Lexer.h:
• parser/NodeConstructors.h:

(JSC::TemplateStringNode::TemplateStringNode):

• parser/Nodes.h:

(JSC::TemplateStringNode::cooked):
(JSC::TemplateStringNode::raw):

• parser/Parser.cpp:

(JSC::Parser<LexerType>::parseAssignmentElement):
(JSC::Parser<LexerType>::parseTemplateString):
(JSC::Parser<LexerType>::parseTemplateLiteral):
(JSC::Parser<LexerType>::parsePrimaryExpression):
(JSC::Parser<LexerType>::parseMemberExpression):

• parser/ParserTokens.h:
• parser/SyntaxChecker.h:

(JSC::SyntaxChecker::createTemplateString):

• runtime/TemplateRegistry.cpp:

(JSC::TemplateRegistry::getTemplateObject):

• runtime/TemplateRegistryKey.h:

(JSC::TemplateRegistryKey::cookedStrings):
(JSC::TemplateRegistryKey::create):
(JSC::TemplateRegistryKey::TemplateRegistryKey):

• runtime/TemplateRegistryKeyTable.cpp:

(JSC::TemplateRegistryKeyTable::createKey):

• runtime/TemplateRegistryKeyTable.h:

LayoutTests:

Update the error messages.

• inspector/runtime/parse-expected.txt:
• js/unicode-escape-sequences-expected.txt:

File:

• trunk/Source/JavaScriptCore/runtime/TemplateRegistry.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/runtime/TemplateRegistry.cpp

@@ -59 +59 @@
 
     for (unsigned index = 0; index < count; ++index) {
-        templateObject->putDirectIndex(exec, index, jsString(exec, templateKey.cookedStrings()[index]), ReadOnly | DontDelete, PutDirectIndexLikePutDirect);
+        auto cooked = templateKey.cookedStrings()[index];
+        if (cooked)
+            templateObject->putDirectIndex(exec, index, jsString(exec, cooked.value()), ReadOnly | DontDelete, PutDirectIndexLikePutDirect);
+        else
+            templateObject->putDirectIndex(exec, index, jsUndefined(), ReadOnly | DontDelete, PutDirectIndexLikePutDirect);
         RETURN_IF_EXCEPTION(scope, nullptr);
+
         rawObject->putDirectIndex(exec, index, jsString(exec, templateKey.rawStrings()[index]), ReadOnly | DontDelete, PutDirectIndexLikePutDirect);
         RETURN_IF_EXCEPTION(scope, nullptr);