Changeset 158793 in webkit for trunk/Source/JavaScriptCore/runtime/Arguments.cpp

Timestamp:

Nov 6, 2013, 2:37:46 PM (12 years ago)

Author:

[email protected]

Message:

Support iteration of the Arguments object
​https://bugs.webkit.org/show_bug.cgi?id=123835

Reviewed by Mark Lam.

Source/JavaScriptCore:

Add an ArgumentsIterator object, and associated classes so that we can support
iteration of the arguments object.

This is a largely mechanical patch. The only gnarliness is in the
logic to avoid reifying the Arguments object in for(... of arguments)
scenarios.

• GNUmakefile.list.am:
• JavaScriptCore.xcodeproj/project.pbxproj:
• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::emitEnumeration):

• runtime/Arguments.cpp:

(JSC::Arguments::getOwnPropertySlot):
(JSC::argumentsFuncIterator):

• runtime/Arguments.h:
• runtime/ArgumentsIteratorConstructor.cpp: Added.

(JSC::ArgumentsIteratorConstructor::finishCreation):

• runtime/ArgumentsIteratorConstructor.h: Added.

(JSC::ArgumentsIteratorConstructor::create):
(JSC::ArgumentsIteratorConstructor::createStructure):
(JSC::ArgumentsIteratorConstructor::ArgumentsIteratorConstructor):

• runtime/ArgumentsIteratorPrototype.cpp: Added.

(JSC::ArgumentsIteratorPrototype::finishCreation):
(JSC::argumentsIteratorPrototypeFuncIterator):
(JSC::argumentsIteratorPrototypeFuncNext):

• runtime/ArgumentsIteratorPrototype.h: Added.

(JSC::ArgumentsIteratorPrototype::create):
(JSC::ArgumentsIteratorPrototype::createStructure):
(JSC::ArgumentsIteratorPrototype::ArgumentsIteratorPrototype):

• runtime/CommonIdentifiers.h:
• runtime/JSArgumentsIterator.cpp: Added.

(JSC::JSArgumentsIterator::finishCreation):

• runtime/JSArgumentsIterator.h: Added.

(JSC::JSArgumentsIterator::createStructure):
(JSC::JSArgumentsIterator::create):
(JSC::JSArgumentsIterator::next):
(JSC::JSArgumentsIterator::JSArgumentsIterator):

• runtime/JSArrayIterator.cpp:

(JSC::createIteratorResult):

• runtime/JSGlobalObject.cpp:
• runtime/JSGlobalObject.h:

LayoutTests:

Add test cases

• js/arguments-iterator-expected.txt: Added.
• js/arguments-iterator.html: Added.
• js/script-tests/arguments-iterator.js: Added.

(shouldThrow.test):
(testAlias):
(testStrict):
(testReifiedArguments):
(testOverwrittenArguments):
(testNullArguments):
(testNonArrayLikeArguments):

File:

• trunk/Source/JavaScriptCore/runtime/Arguments.cpp (modified) (4 diffs)

trunk/Source/JavaScriptCore/runtime/Arguments.cpp

@@ -28 +28 @@
 #include "CallFrameInlines.h"
 #include "JSActivation.h"
+#include "JSArgumentsIterator.h"
 #include "JSFunction.h"
 #include "JSGlobalObject.h"
@@ -51 +52 @@
     visitor.append(&thisObject->m_activation);
 }
+    
+static EncodedJSValue JSC_HOST_CALL argumentsFuncIterator(ExecState*);
 
 void Arguments::destroy(JSCell* cell)
@@ -152 +155 @@
         thisObject->createStrictModeCallerIfNecessary(exec);
 
-    return JSObject::getOwnPropertySlot(thisObject, exec, propertyName, slot);
+    if (JSObject::getOwnPropertySlot(thisObject, exec, propertyName, slot))
+        return true;
+    if (propertyName == exec->propertyNames().iteratorPrivateName) {
+        VM& vm = exec->vm();
+        JSGlobalObject* globalObject = exec->lexicalGlobalObject();
+        thisObject->JSC_NATIVE_FUNCTION(exec->propertyNames().iteratorPrivateName, argumentsFuncIterator, DontEnum, 0);
+        if (JSObject::getOwnPropertySlot(thisObject, exec, propertyName, slot))
+            return true;
+    }
+    return false;
 }
 
@@ -362 +374 @@
     }
 }
+    
+EncodedJSValue JSC_HOST_CALL argumentsFuncIterator(ExecState* exec)
+{
+    JSObject* thisObj = exec->hostThisValue().toThis(exec, StrictMode).toObject(exec);
+    Arguments* arguments = jsDynamicCast<Arguments*>(thisObj);
+    if (!arguments)
+        return JSValue::encode(throwTypeError(exec, "Attempted to use Arguments iterator on non-Arguments object"));
+    return JSValue::encode(JSArgumentsIterator::create(exec->vm(), exec->callee()->globalObject()->argumentsIteratorStructure(), arguments));
+}
+
 
 } // namespace JSC