Changeset 291577 in webkit for trunk/Source/JavaScriptCore/parser/Parser.cpp

Timestamp:

Mar 21, 2022, 12:57:19 PM (3 years ago)

Author:

[email protected]

Message:

[JSC] ReferenceError when using extra parens in class fields
​https://bugs.webkit.org/show_bug.cgi?id=236843

Reviewed by Saam Barati.

JSTests:

• stress/class-field-initializer-should-have-variable-scope.js: Added.

(shouldBe):
(test1.const.a.x.B):
(test1):
(test2.const.a.x.B):
(test2):
(test3.B.prototype.b):
(test3.B):
(test3):

Source/JavaScriptCore:

class field initializer should create its own used-variables set
to capture used variables separately from the other variables since
it becomes independent CodeBlock internally later. The current code
was wrong since,

1. Incorrectly using the current set of class-scope.
2. Incorrectly marking only the last set while parseAssignmentExpression can create a new set inside it.

• parser/Parser.cpp:

(JSC::Parser<LexerType>::parseClass):

• parser/Parser.h:

(JSC::Scope::markLastUsedVariablesSetAsCaptured):

File:

• trunk/Source/JavaScriptCore/parser/Parser.cpp (modified) (2 diffs)

trunk/Source/JavaScriptCore/parser/Parser.cpp

@@ -3111 +3111 @@
             TreeExpression initializer = 0;
             if (consume(EQUAL)) {
+                size_t usedVariablesSize = currentScope()->currentUsedVariablesSize();
+                currentScope()->pushUsedVariableSet();
                 SetForScope overrideParsingClassFieldInitializer(m_parserState.isParsingClassFieldInitializer, true);
                 classScope->setExpectedSuperBinding(SuperBinding::Needed);
@@ -3116 +3118 @@
                 classScope->setExpectedSuperBinding(SuperBinding::NotNeeded);
                 failIfFalse(initializer, "Cannot parse initializer for class field");
-                classScope->markLastUsedVariablesSetAsCaptured();
+                classScope->markLastUsedVariablesSetAsCaptured(usedVariablesSize);
             }
             failIfFalse(autoSemiColon(), "Expected a ';' following a class field");