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<dt>Revision</dt> <dd><a href="http://trac.webkit.org/projects/webkit/changeset/197970">197970</a></dd>
<dt>Author</dt> <dd>sbarati@apple.com</dd>
<dt>Date</dt> <dd>2016-03-10 16:43:46 -0800 (Thu, 10 Mar 2016)</dd>
</dl>
<h3>Log Message</h3>
<pre>[ES6] Instanceof isn't spec compliant when the RHS is a Proxy with a target that is a function
https://bugs.webkit.org/show_bug.cgi?id=155329
Reviewed by Mark Lam.
We use type info flags on the structure to dictate whether or not
the RHS of an instanceof is a valid RHS (i.e, a function). The solution
to make Proxy a valid RHS when the Proxy's target is callable is to have
two different structures for ProxyObject: one for a non-callable target
and one for a callable target.
* runtime/JSGlobalObject.cpp:
(JSC::JSGlobalObject::init):
(JSC::JSGlobalObject::visitChildren):
* runtime/JSGlobalObject.h:
(JSC::JSGlobalObject::moduleRecordStructure):
(JSC::JSGlobalObject::moduleNamespaceObjectStructure):
(JSC::JSGlobalObject::proxyObjectStructure):
(JSC::JSGlobalObject::callableProxyObjectStructure):
(JSC::JSGlobalObject::proxyRevokeStructure):
(JSC::JSGlobalObject::wasmModuleStructure):
* runtime/ProxyConstructor.cpp:
(JSC::makeRevocableProxy):
(JSC::constructProxyObject):
(JSC::ProxyConstructor::getConstructData):
* runtime/ProxyObject.cpp:
(JSC::ProxyObject::ProxyObject):
(JSC::ProxyObject::structureForTarget):
(JSC::ProxyObject::finishCreation):
* runtime/ProxyObject.h:
(JSC::ProxyObject::create):
(JSC::ProxyObject::createStructure):
* tests/es6.yaml:
* tests/stress/proxy-instanceof.js: Added.
(assert):
(test):
(C):
(test.let.handler.get if):
(test.let.handler):</pre>
<h3>Modified Paths</h3>
<ul>
<li><a href="#trunkSourceJavaScriptCoreChangeLog">trunk/Source/JavaScriptCore/ChangeLog</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeJSGlobalObjectcpp">trunk/Source/JavaScriptCore/runtime/JSGlobalObject.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeJSGlobalObjecth">trunk/Source/JavaScriptCore/runtime/JSGlobalObject.h</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeProxyConstructorcpp">trunk/Source/JavaScriptCore/runtime/ProxyConstructor.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeProxyObjectcpp">trunk/Source/JavaScriptCore/runtime/ProxyObject.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeProxyObjecth">trunk/Source/JavaScriptCore/runtime/ProxyObject.h</a></li>
<li><a href="#trunkSourceJavaScriptCoretestses6yaml">trunk/Source/JavaScriptCore/tests/es6.yaml</a></li>
</ul>
<h3>Added Paths</h3>
<ul>
<li><a href="#trunkSourceJavaScriptCoretestsstressproxyinstanceofjs">trunk/Source/JavaScriptCore/tests/stress/proxy-instanceof.js</a></li>
</ul>
</div>
<div id="patch">
<h3>Diff</h3>
<a id="trunkSourceJavaScriptCoreChangeLog"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/ChangeLog (197969 => 197970)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/ChangeLog 2016-03-11 00:42:18 UTC (rev 197969)
+++ trunk/Source/JavaScriptCore/ChangeLog 2016-03-11 00:43:46 UTC (rev 197970)
</span><span class="lines">@@ -1,3 +1,45 @@
</span><ins>+2016-03-10 Saam barati <sbarati@apple.com>
+
+ [ES6] Instanceof isn't spec compliant when the RHS is a Proxy with a target that is a function
+ https://bugs.webkit.org/show_bug.cgi?id=155329
+
+ Reviewed by Mark Lam.
+
+ We use type info flags on the structure to dictate whether or not
+ the RHS of an instanceof is a valid RHS (i.e, a function). The solution
+ to make Proxy a valid RHS when the Proxy's target is callable is to have
+ two different structures for ProxyObject: one for a non-callable target
+ and one for a callable target.
+
+ * runtime/JSGlobalObject.cpp:
+ (JSC::JSGlobalObject::init):
+ (JSC::JSGlobalObject::visitChildren):
+ * runtime/JSGlobalObject.h:
+ (JSC::JSGlobalObject::moduleRecordStructure):
+ (JSC::JSGlobalObject::moduleNamespaceObjectStructure):
+ (JSC::JSGlobalObject::proxyObjectStructure):
+ (JSC::JSGlobalObject::callableProxyObjectStructure):
+ (JSC::JSGlobalObject::proxyRevokeStructure):
+ (JSC::JSGlobalObject::wasmModuleStructure):
+ * runtime/ProxyConstructor.cpp:
+ (JSC::makeRevocableProxy):
+ (JSC::constructProxyObject):
+ (JSC::ProxyConstructor::getConstructData):
+ * runtime/ProxyObject.cpp:
+ (JSC::ProxyObject::ProxyObject):
+ (JSC::ProxyObject::structureForTarget):
+ (JSC::ProxyObject::finishCreation):
+ * runtime/ProxyObject.h:
+ (JSC::ProxyObject::create):
+ (JSC::ProxyObject::createStructure):
+ * tests/es6.yaml:
+ * tests/stress/proxy-instanceof.js: Added.
+ (assert):
+ (test):
+ (C):
+ (test.let.handler.get if):
+ (test.let.handler):
+
</ins><span class="cx"> 2016-03-10 Michael Saboff <msaboff@apple.com>
</span><span class="cx">
</span><span class="cx"> [ES6] RegExp sticky flag should be ignored in String.match when global flag is given
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeJSGlobalObjectcpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/JSGlobalObject.cpp (197969 => 197970)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/JSGlobalObject.cpp 2016-03-11 00:42:18 UTC (rev 197969)
+++ trunk/Source/JavaScriptCore/runtime/JSGlobalObject.cpp 2016-03-11 00:43:46 UTC (rev 197970)
</span><span class="lines">@@ -370,7 +370,12 @@
</span><span class="cx">
</span><span class="cx"> m_moduleRecordStructure.set(vm, this, JSModuleRecord::createStructure(vm, this, m_objectPrototype.get()));
</span><span class="cx"> m_moduleNamespaceObjectStructure.set(vm, this, JSModuleNamespaceObject::createStructure(vm, this, jsNull()));
</span><del>- m_proxyObjectStructure.set(vm, this, ProxyObject::createStructure(vm, this, m_objectPrototype.get()));
</del><ins>+ {
+ bool isCallable = false;
+ m_proxyObjectStructure.set(vm, this, ProxyObject::createStructure(vm, this, m_objectPrototype.get(), isCallable));
+ isCallable = true;
+ m_callableProxyObjectStructure.set(vm, this, ProxyObject::createStructure(vm, this, m_objectPrototype.get(), isCallable));
+ }
</ins><span class="cx"> m_proxyRevokeStructure.set(vm, this, ProxyRevoke::createStructure(vm, this, m_functionPrototype.get()));
</span><span class="cx">
</span><span class="cx"> #if ENABLE(WEBASSEMBLY)
</span><span class="lines">@@ -913,6 +918,7 @@
</span><span class="cx"> visitor.append(&thisObject->m_dollarVMStructure);
</span><span class="cx"> visitor.append(&thisObject->m_internalFunctionStructure);
</span><span class="cx"> visitor.append(&thisObject->m_proxyObjectStructure);
</span><ins>+ visitor.append(&thisObject->m_callableProxyObjectStructure);
</ins><span class="cx"> visitor.append(&thisObject->m_proxyRevokeStructure);
</span><span class="cx"> #if ENABLE(WEBASSEMBLY)
</span><span class="cx"> visitor.append(&thisObject->m_wasmModuleStructure);
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeJSGlobalObjecth"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/JSGlobalObject.h (197969 => 197970)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/JSGlobalObject.h 2016-03-11 00:42:18 UTC (rev 197969)
+++ trunk/Source/JavaScriptCore/runtime/JSGlobalObject.h 2016-03-11 00:43:46 UTC (rev 197970)
</span><span class="lines">@@ -282,6 +282,7 @@
</span><span class="cx"> WriteBarrier<Structure> m_moduleRecordStructure;
</span><span class="cx"> WriteBarrier<Structure> m_moduleNamespaceObjectStructure;
</span><span class="cx"> WriteBarrier<Structure> m_proxyObjectStructure;
</span><ins>+ WriteBarrier<Structure> m_callableProxyObjectStructure;
</ins><span class="cx"> WriteBarrier<Structure> m_proxyRevokeStructure;
</span><span class="cx"> #if ENABLE(WEBASSEMBLY)
</span><span class="cx"> WriteBarrier<Structure> m_wasmModuleStructure;
</span><span class="lines">@@ -536,6 +537,7 @@
</span><span class="cx"> Structure* moduleRecordStructure() const { return m_moduleRecordStructure.get(); }
</span><span class="cx"> Structure* moduleNamespaceObjectStructure() const { return m_moduleNamespaceObjectStructure.get(); }
</span><span class="cx"> Structure* proxyObjectStructure() const { return m_proxyObjectStructure.get(); }
</span><ins>+ Structure* callableProxyObjectStructure() const { return m_callableProxyObjectStructure.get(); }
</ins><span class="cx"> Structure* proxyRevokeStructure() const { return m_proxyRevokeStructure.get(); }
</span><span class="cx"> #if ENABLE(WEBASSEMBLY)
</span><span class="cx"> Structure* wasmModuleStructure() const { return m_wasmModuleStructure.get(); }
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeProxyConstructorcpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/ProxyConstructor.cpp (197969 => 197970)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/ProxyConstructor.cpp 2016-03-11 00:42:18 UTC (rev 197969)
+++ trunk/Source/JavaScriptCore/runtime/ProxyConstructor.cpp 2016-03-11 00:43:46 UTC (rev 197970)
</span><span class="lines">@@ -63,7 +63,7 @@
</span><span class="cx"> ArgList args(exec);
</span><span class="cx"> JSValue target = args.at(0);
</span><span class="cx"> JSValue handler = args.at(1);
</span><del>- ProxyObject* proxy = ProxyObject::create(exec, exec->lexicalGlobalObject()->proxyObjectStructure(), target, handler);
</del><ins>+ ProxyObject* proxy = ProxyObject::create(exec, exec->lexicalGlobalObject(), target, handler);
</ins><span class="cx"> if (vm.exception())
</span><span class="cx"> return JSValue::encode(JSValue());
</span><span class="cx"> ProxyRevoke* revoke = ProxyRevoke::create(vm, exec->lexicalGlobalObject()->proxyRevokeStructure(), proxy);
</span><span class="lines">@@ -100,7 +100,7 @@
</span><span class="cx"> ArgList args(exec);
</span><span class="cx"> JSValue target = args.at(0);
</span><span class="cx"> JSValue handler = args.at(1);
</span><del>- return JSValue::encode(ProxyObject::create(exec, exec->lexicalGlobalObject()->proxyObjectStructure(), target, handler));
</del><ins>+ return JSValue::encode(ProxyObject::create(exec, exec->lexicalGlobalObject(), target, handler));
</ins><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> ConstructType ProxyConstructor::getConstructData(JSCell*, ConstructData& constructData)
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeProxyObjectcpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/ProxyObject.cpp (197969 => 197970)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/ProxyObject.cpp 2016-03-11 00:42:18 UTC (rev 197969)
+++ trunk/Source/JavaScriptCore/runtime/ProxyObject.cpp 2016-03-11 00:43:46 UTC (rev 197970)
</span><span class="lines">@@ -45,6 +45,17 @@
</span><span class="cx"> {
</span><span class="cx"> }
</span><span class="cx">
</span><ins>+Structure* ProxyObject::structureForTarget(JSGlobalObject* globalObject, JSValue target)
+{
+ if (!target.isObject())
+ return globalObject->proxyObjectStructure();
+
+ JSObject* targetAsObject = jsCast<JSObject*>(target);
+ CallData ignoredCallData;
+ bool isCallable = targetAsObject->methodTable()->getCallData(targetAsObject, ignoredCallData) != CallType::None;
+ return isCallable ? globalObject->callableProxyObjectStructure() : globalObject->proxyObjectStructure();
+}
+
</ins><span class="cx"> void ProxyObject::finishCreation(VM& vm, ExecState* exec, JSValue target, JSValue handler)
</span><span class="cx"> {
</span><span class="cx"> Base::finishCreation(vm);
</span><span class="lines">@@ -67,6 +78,10 @@
</span><span class="cx">
</span><span class="cx"> CallData ignoredCallData;
</span><span class="cx"> m_isCallable = targetAsObject->methodTable(vm)->getCallData(targetAsObject, ignoredCallData) != CallType::None;
</span><ins>+ if (m_isCallable) {
+ TypeInfo info = structure(vm)->typeInfo();
+ RELEASE_ASSERT(info.implementsHasInstance() && info.implementsDefaultHasInstance());
+ }
</ins><span class="cx">
</span><span class="cx"> ConstructData ignoredConstructData;
</span><span class="cx"> m_isConstructible = jsCast<JSObject*>(target)->methodTable(vm)->getConstructData(jsCast<JSObject*>(target), ignoredConstructData) != ConstructType::None;
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeProxyObjecth"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/ProxyObject.h (197969 => 197970)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/ProxyObject.h 2016-03-11 00:42:18 UTC (rev 197969)
+++ trunk/Source/JavaScriptCore/runtime/ProxyObject.h 2016-03-11 00:43:46 UTC (rev 197970)
</span><span class="lines">@@ -40,17 +40,20 @@
</span><span class="cx"> // property name enumeration caching.
</span><span class="cx"> const static unsigned StructureFlags = Base::StructureFlags | OverridesGetOwnPropertySlot | TypeOfShouldCallGetCallData | InterceptsGetOwnPropertySlotByIndexEvenWhenLengthIsNotZero | OverridesGetPropertyNames | ProhibitsPropertyCaching;
</span><span class="cx">
</span><del>- static ProxyObject* create(ExecState* exec, Structure* structure, JSValue target, JSValue handler)
</del><ins>+ static ProxyObject* create(ExecState* exec, JSGlobalObject* globalObject, JSValue target, JSValue handler)
</ins><span class="cx"> {
</span><span class="cx"> VM& vm = exec->vm();
</span><del>- ProxyObject* proxy = new (NotNull, allocateCell<ProxyObject>(vm.heap)) ProxyObject(vm, structure);
</del><ins>+ ProxyObject* proxy = new (NotNull, allocateCell<ProxyObject>(vm.heap)) ProxyObject(vm, ProxyObject::structureForTarget(globalObject, target));
</ins><span class="cx"> proxy->finishCreation(vm, exec, target, handler);
</span><span class="cx"> return proxy;
</span><span class="cx"> }
</span><span class="cx">
</span><del>- static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
</del><ins>+ static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype, bool isCallable)
</ins><span class="cx"> {
</span><del>- Structure* result = Structure::create(vm, globalObject, prototype, TypeInfo(ProxyObjectType, StructureFlags), info(), NonArray | MayHaveIndexedAccessors);
</del><ins>+ unsigned flags = StructureFlags;
+ if (isCallable)
+ flags |= (ImplementsHasInstance | ImplementsDefaultHasInstance);
+ Structure* result = Structure::create(vm, globalObject, prototype, TypeInfo(ProxyObjectType, flags), info(), NonArray | MayHaveIndexedAccessors);
</ins><span class="cx"> result->setIsQuickPropertyAccessAllowedForEnumeration(false);
</span><span class="cx"> RELEASE_ASSERT(!result->canAccessPropertiesQuicklyForEnumeration());
</span><span class="cx"> RELEASE_ASSERT(!result->canCachePropertyNameEnumerator());
</span><span class="lines">@@ -72,6 +75,7 @@
</span><span class="cx"> private:
</span><span class="cx"> ProxyObject(VM&, Structure*);
</span><span class="cx"> void finishCreation(VM&, ExecState*, JSValue target, JSValue handler);
</span><ins>+ static Structure* structureForTarget(JSGlobalObject*, JSValue target);
</ins><span class="cx">
</span><span class="cx"> static bool getOwnPropertySlot(JSObject*, ExecState*, PropertyName, PropertySlot&);
</span><span class="cx"> static bool getOwnPropertySlotByIndex(JSObject*, ExecState*, unsigned propertyName, PropertySlot&);
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoretestses6yaml"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/tests/es6.yaml (197969 => 197970)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/tests/es6.yaml 2016-03-11 00:42:18 UTC (rev 197969)
+++ trunk/Source/JavaScriptCore/tests/es6.yaml 2016-03-11 00:43:46 UTC (rev 197970)
</span><span class="lines">@@ -979,7 +979,7 @@
</span><span class="cx"> - path: es6/Proxy_internal_get_calls_HasBinding.js
</span><span class="cx"> cmd: runES6 :normal
</span><span class="cx"> - path: es6/Proxy_internal_get_calls_instanceof_operator.js
</span><del>- cmd: runES6 :fail
</del><ins>+ cmd: runES6 :normal
</ins><span class="cx"> - path: es6/Proxy_internal_get_calls_IteratorComplete_IteratorValue.js
</span><span class="cx"> cmd: runES6 :normal
</span><span class="cx"> - path: es6/Proxy_internal_get_calls_JSON.stringify.js
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoretestsstressproxyinstanceofjs"></a>
<div class="addfile"><h4>Added: trunk/Source/JavaScriptCore/tests/stress/proxy-instanceof.js (0 => 197970)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/tests/stress/proxy-instanceof.js (rev 0)
+++ trunk/Source/JavaScriptCore/tests/stress/proxy-instanceof.js 2016-03-11 00:43:46 UTC (rev 197970)
</span><span class="lines">@@ -0,0 +1,39 @@
</span><ins>+function assert(b) {
+ if (!b)
+ throw new Error("Bad assertion");
+}
+
+function test(f) {
+ for (let i = 0; i < 1000; i++)
+ f();
+}
+
+let constructors = [Error, String, RegExp, function() {}, class C {}];
+
+for (let constructor of constructors) {
+ test(function() {
+ let proxy = new Proxy(constructor, {});
+ assert(new constructor instanceof proxy);
+ });
+}
+
+test(function() {
+ let called = false;
+ let proxy = new Proxy(function(){ called = true; }, {});
+ assert(new proxy instanceof proxy);
+ assert(called);
+});
+
+test(function() {
+ let called = false;
+ let handler = {
+ get: function(target, prop) {
+ if (prop === "prototype")
+ return {};
+ return target[prop];
+ }
+ };
+ let proxy = new Proxy(function(){ called = true; }, handler);
+ assert(!(new proxy instanceof proxy));
+ assert(called);
+});
</ins></span></pre>
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