Changeset 223232 in webkit for trunk/Source/JavaScriptCore/parser/Parser.cpp

Timestamp:

Oct 11, 2017, 11:45:23 PM (8 years ago)

Author:

Yusuke Suzuki

Message:

import.meta should not be assignable
​https://bugs.webkit.org/show_bug.cgi?id=178202

Reviewed by Saam Barati.

JSTests:

• modules/import-meta-assignment.js: Added.

(shouldThrow):
(SyntaxError.import.meta.can.shouldThrow):

Source/JavaScriptCore:

import.meta cannot be used for LHS. This patch adds MetaPropertyNode
and make NewTargetNode and ImportMetaNode as derived classes of MetaPropertyNode.
We change the parser not to allow assignments for MetaPropertyNode.

• bytecompiler/NodesCodegen.cpp:

(JSC::ImportMetaNode::emitBytecode):

• parser/ASTBuilder.h:

(JSC::ASTBuilder::createImportMetaExpr):
(JSC::ASTBuilder::isMetaProperty):
(JSC::ASTBuilder::isImportMeta):

• parser/NodeConstructors.h:

(JSC::MetaPropertyNode::MetaPropertyNode):
(JSC::NewTargetNode::NewTargetNode):
(JSC::ImportMetaNode::ImportMetaNode):

• parser/Nodes.h:

(JSC::ExpressionNode::isMetaProperty const):
(JSC::ExpressionNode::isImportMeta const):

• parser/Parser.cpp:

(JSC::Parser<LexerType>::metaPropertyName):
(JSC::Parser<LexerType>::parseAssignmentExpression):
(JSC::Parser<LexerType>::parseMemberExpression):
(JSC::Parser<LexerType>::parseUnaryExpression):

• parser/Parser.h:
• parser/SyntaxChecker.h:

(JSC::SyntaxChecker::createImportMetaExpr):
(JSC::SyntaxChecker::isMetaProperty):
(JSC::SyntaxChecker::isImportMeta):

File:

• trunk/Source/JavaScriptCore/parser/Parser.cpp (modified) (6 diffs)

trunk/Source/JavaScriptCore/parser/Parser.cpp

@@ -3586 +3586 @@
     return parseAssignmentExpression(context, classifier);
 }
+
+
+template <typename LexerType>
+template <typename TreeBuilder> NEVER_INLINE const char* Parser<LexerType>::metaPropertyName(TreeBuilder& context, TreeExpression expr)
+{
+    if (context.isNewTarget(expr))
+        return "new.target";
+    if (context.isImportMeta(expr))
+        return "import.meta";
+    RELEASE_ASSERT_NOT_REACHED();
+    return "error";
+}
     
 template <typename LexerType>
@@ -3691 +3703 @@
         m_parserState.nonTrivialExpressionCount++;
         hadAssignment = true;
-        if (UNLIKELY(context.isNewTarget(lhs)))
-            internalFailWithMessage(false, "new.target can't be the left hand side of an assignment expression");
+        if (UNLIKELY(context.isMetaProperty(lhs)))
+            internalFailWithMessage(false, metaPropertyName(context, lhs), " can't be the left hand side of an assignment expression");
         context.assignmentStackAppend(assignmentStack, lhs, start, tokenStartPosition(), m_parserState.assignmentCount, op);
         start = tokenStartPosition();
@@ -4699 +4711 @@
 
                 JSTokenLocation location(tokenLocation());
-                base = createResolveAndUseVariable(context, &m_vm->propertyNames->builtinNames().metaPrivateName(), false, expressionStart, location);
+                base = context.createImportMetaExpr(location, createResolveAndUseVariable(context, &m_vm->propertyNames->builtinNames().metaPrivateName(), false, expressionStart, location));
                 next();
             } else {
@@ -4925 +4937 @@
         failWithMessage("Cannot parse member expression");
     }
-    if (UNLIKELY(isUpdateOp(static_cast<JSTokenType>(lastOperator)) && context.isNewTarget(expr)))
-        internalFailWithMessage(false, "new.target can't come after a prefix operator");
+    if (UNLIKELY(isUpdateOp(static_cast<JSTokenType>(lastOperator)) && context.isMetaProperty(expr)))
+        internalFailWithMessage(false, metaPropertyName(context, expr), " can't come after a prefix operator");
     bool isEvalOrArguments = false;
     if (strictMode() && !m_syntaxAlreadyValidated) {
@@ -4935 +4947 @@
     switch (m_token.m_type) {
     case PLUSPLUS:
-        if (UNLIKELY(context.isNewTarget(expr)))
-            internalFailWithMessage(false, "new.target can't come before a postfix operator");
+        if (UNLIKELY(context.isMetaProperty(expr)))
+            internalFailWithMessage(false, metaPropertyName(context, expr), " can't come before a postfix operator");
         m_parserState.nonTrivialExpressionCount++;
         m_parserState.nonLHSCount++;
@@ -4947 +4959 @@
         break;
     case MINUSMINUS:
-        if (UNLIKELY(context.isNewTarget(expr)))
-            internalFailWithMessage(false, "new.target can't come before a postfix operator");
+        if (UNLIKELY(context.isMetaProperty(expr)))
+            internalFailWithMessage(false, metaPropertyName(context, expr), " can't come before a postfix operator");
         m_parserState.nonTrivialExpressionCount++;
         m_parserState.nonLHSCount++;