Changeset 179371 in webkit for trunk/Source/JavaScriptCore/parser/Nodes.h

Timestamp:

Jan 29, 2015, 2:59:19 PM (10 years ago)

Author:

[email protected]

Message:

Implement ES6 class syntax without inheritance support
​https://bugs.webkit.org/show_bug.cgi?id=140918

Reviewed by Geoffrey Garen.

Source/JavaScriptCore:

Added the most basic support for ES6 class syntax. After this patch, we support basic class definition like:
class A {

constructor() { }
someMethod() { }

}

We'll add the support for "extends" keyword and automatically generating a constructor in follow up patches.
We also don't support block scoping of a class declaration.

We support both class declaration and class expression. A class expression is implemented by the newly added
ClassExprNode AST node. A class declaration is implemented by ClassDeclNode, which is a thin wrapper around
AssignResolveNode.

Tests: js/class-syntax-declaration.html

js/class-syntax-expression.html

• bytecompiler/NodesCodegen.cpp:

(JSC::ObjectLiteralNode::emitBytecode): Create a new object instead of delegating the work to PropertyListNode.
Also fixed the 5-space indentation.
(JSC::PropertyListNode::emitBytecode): Don't create a new object now that ObjectLiteralNode does this.
(JSC::ClassDeclNode::emitBytecode): Added. Just let the AssignResolveNode node emit the byte code.
(JSC::ClassExprNode::emitBytecode): Create the class constructor and add static methods to the constructor by
emitting the byte code for PropertyListNode. Add instance methods to the class's prototype object the same way.

• parser/ASTBuilder.h:

(JSC::ASTBuilder::createClassExpr): Added. Creates a ClassExprNode.
(JSC::ASTBuilder::createClassDeclStatement): Added. Creates a AssignResolveNode and wraps it by a ClassDeclNode.

• parser/NodeConstructors.h:

(JSC::ClassDeclNode::ClassDeclNode): Added.
(JSC::ClassExprNode::ClassExprNode): Added.

• parser/Nodes.h:

(JSC::ClassExprNode): Added.
(JSC::ClassDeclNode): Added.

• parser/Parser.cpp:

(JSC::Parser<LexerType>::parseStatement): Added the support for class declaration.
(JSC::stringForFunctionMode): Return "method" for MethodMode.
(JSC::Parser<LexerType>::parseClassDeclaration): Added. Uses parseClass to create a class expression and wraps
it with ClassDeclNode as described above.
(JSC::Parser<LexerType>::parseClass): Parses a class expression.
(JSC::Parser<LexerType>::parseProperty):
(JSC::Parser<LexerType>::parseGetterSetter): Extracted from parseProperty to share the code between parseProperty
and parseClass.
(JSC::Parser<LexerType>::parsePrimaryExpression): Added the support for class expression.

• parser/Parser.h:

(FunctionParseMode): Added MethodMode.

• parser/SyntaxChecker.h:

(JSC::SyntaxChecker::createClassExpr): Added.
(JSC::SyntaxChecker::createClassDeclStatement): Added.

LayoutTests:

Added two tests for class declarations and class expressions.

• TestExpectations:
• js/class-syntax-declaration-expected.txt: Added.
• js/class-syntax-declaration.html: Added.
• js/class-syntax-expression-expected.txt: Added.
• js/class-syntax-expression.html: Added.
• js/script-tests/class-syntax-declaration.js: Added.
• js/script-tests/class-syntax-expression.js: Added.

File:

• trunk/Source/JavaScriptCore/parser/Nodes.h (modified) (2 diffs)

trunk/Source/JavaScriptCore/parser/Nodes.h

@@ -1612 +1612 @@
     };
 
+#if ENABLE(ES6_CLASS_SYNTAX)
+    class ClassExprNode final : public ExpressionNode {
+    public:
+        ClassExprNode(const JSTokenLocation&, const Identifier&, ExpressionNode* constructorExpresssion,
+            ExpressionNode* parentClass, PropertyListNode* instanceMethods, PropertyListNode* staticMethods);
+
+        const Identifier& name() { return m_name; }
+
+    private:
+        virtual RegisterID* emitBytecode(BytecodeGenerator&, RegisterID* = 0) override;
+
+        const Identifier& m_name;
+        ExpressionNode* m_constructorExpression;
+        ExpressionNode* m_parentClassExpression;
+        PropertyListNode* m_instanceMethods;
+        PropertyListNode* m_staticMethods;
+    };
+#endif
+
     class DeconstructionPatternNode : public RefCounted<DeconstructionPatternNode> {
         WTF_MAKE_NONCOPYABLE(DeconstructionPatternNode);
@@ -1725 +1744 @@
     };
 
+#if ENABLE(ES6_CLASS_SYNTAX)
+    class ClassDeclNode final : public StatementNode {
+    public:
+        ClassDeclNode(const JSTokenLocation&, ExpressionNode* classExpression);
+
+    private:
+        virtual void emitBytecode(BytecodeGenerator&, RegisterID* = 0) override;
+
+        ExpressionNode* m_classDeclaration;
+    };
+#endif
+
     class CaseClauseNode : public ParserArenaFreeable {
     public: