Changeset 204078 in webkit for trunk/Source/JavaScriptCore/parser/SyntaxChecker.h

Timestamp:

Aug 3, 2016, 12:50:40 AM (9 years ago)

Author:

[email protected]

Message:

Implement nested rest destructuring w.r.t the ES7 spec
​https://bugs.webkit.org/show_bug.cgi?id=160423

Reviewed by Filip Pizlo.

JSTests:

• stress/destructuring-rest-element.js: Added.

(assert):
(test):
(arr):
(eq):
(gen):
(fakeGen.return.Symbol.iterator):
(fakeGen):

• stress/rest-elements.js:

(testSyntaxError.String.raw):

• stress/rest-parameter-is-destructuring.js: Added.

(assert):
(test):
(foo):
(bar):

• test262.yaml:

Source/JavaScriptCore:

The spec has updated the BindingRestElement grammar production to be:
BindingRestElement:

BindingIdentifier
BindingingPattern.

It used to only allow BindingIdentifier in the grammar production.
I've updated our engine to account for this. The semantics are exactly
what you'd expect. For example:
let [a, ...[b, ...c]] = expr();
means that we create an array for the first rest element ...[b, ...c]
and then perform the binding of [b, ...c] to that array. And so on,
applied recursively through the pattern.

• bytecompiler/NodesCodegen.cpp:

(JSC::RestParameterNode::collectBoundIdentifiers):
(JSC::RestParameterNode::toString):
(JSC::RestParameterNode::bindValue):
(JSC::RestParameterNode::emit):

• parser/ASTBuilder.h:

(JSC::ASTBuilder::createBindingLocation):
(JSC::ASTBuilder::createRestParameter):
(JSC::ASTBuilder::createAssignmentElement):

• parser/NodeConstructors.h:

(JSC::AssignmentElementNode::AssignmentElementNode):
(JSC::RestParameterNode::RestParameterNode):
(JSC::DestructuringAssignmentNode::DestructuringAssignmentNode):

• parser/Nodes.h:

(JSC::RestParameterNode::name): Deleted.

• parser/Parser.cpp:

(JSC::Parser<LexerType>::parseDestructuringPattern):
(JSC::Parser<LexerType>::parseFormalParameters):

• parser/SyntaxChecker.h:

(JSC::SyntaxChecker::operatorStackPop):

LayoutTests:

• js/parser-syntax-check-expected.txt:
• js/script-tests/parser-syntax-check.js:

File:

• trunk/Source/JavaScriptCore/parser/SyntaxChecker.h (modified) (1 diff)

trunk/Source/JavaScriptCore/parser/SyntaxChecker.h

@@ -355 +355 @@
         return BindingDestructuring;
     }
-    RestPattern createRestParameter(const Identifier&, size_t, const JSTextPosition&, const JSTextPosition&)
+    RestPattern createRestParameter(DestructuringPattern, size_t)
     { 
         return RestParameter;