Bug 1246318 - Remove the enumerate trap from ES6 proxies. r=efaust

addon-sdk/source/lib/sdk/preferences/service.js

@@ -37,9 +37,6 @@ const Branch = function(branchName) {
         value: this.get(target, name, receiver)
       };
     },
-    enumerate(target) {
-      return branchKeys(branchName)[Symbol.iterator]();
-    },
     ownKeys(target) {
       return branchKeys(branchName);
     },

js/src/jit-test/tests/proxy/testDirectProxyEnumerate2.js

@@ -1,16 +0,0 @@
-// Throwing [[Enumerate]] handler
-load(libdir + "asserts.js");
-
-let handler = new Proxy({}, {
-    get: function(target, name) {
-        assertEq(name, "enumerate");
-        throw new SyntaxError();
-    }
-});
-
-let proxy = new Proxy({}, handler);
-
-assertThrowsInstanceOf(function() {
-    for (let x in proxy)
-        assertEq(true, false);
-}, SyntaxError)

js/src/jit-test/tests/proxy/testDirectProxyEnumerate3.js

@@ -1,16 +0,0 @@
-// Basic [[Enumerate]] functionality test
-let inner = [];
-let handler = {
-    enumerate: function(target) {
-        assertEq(target, inner);
-        assertEq(arguments.length, 1);
-        assertEq(this, handler);
-        return (function*() { yield 'a'; })();
-    }
-};
-
-let x;
-for (let y in new Proxy(inner, handler)) {
-    x = y;
-}
-assertEq(x, 'a');

js/src/jit-test/tests/proxy/testDirectProxyEnumerate4.js

@@ -1,15 +0,0 @@
-// Returning primitive from [[Enumerate]] handler
-load(libdir + "asserts.js");
-
-let handler = {
-    enumerate: function() {
-        return undefined;
-    }
-};
-
-let proxy = new Proxy({}, handler);
-
-assertThrowsInstanceOf(function() {
-    for (let x in proxy)
-        assertEq(true, false);
-}, TypeError)

js/src/proxy/ScriptedDirectProxyHandler.cpp

@@ -724,52 +724,6 @@ ScriptedDirectProxyHandler::delete_(JSContext* cx, HandleObject proxy, HandleId
     return result.succeed();
 }
 
-// ES6 (14 October, 2014) 9.5.11 Proxy.[[Enumerate]]
-bool
-ScriptedDirectProxyHandler::enumerate(JSContext* cx, HandleObject proxy,
-                                      MutableHandleObject objp) const
-{
-    // step 1
-    RootedObject handler(cx, GetDirectProxyHandlerObject(proxy));
-
-    // step 2
-    if (!handler) {
-        JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_PROXY_REVOKED);
-        return false;
-    }
-
-    // step 3: unnecessary assert
-    // step 4
-    RootedObject target(cx, proxy->as<ProxyObject>().target());
-
-    // step 5-6
-    RootedValue trap(cx);
-    if (!GetProperty(cx, handler, handler, cx->names().enumerate, &trap))
-        return false;
-
-    // step 7
-    if (trap.isUndefined())
-        return GetIterator(cx, target, 0, objp);
-
-    // step 8-9
-    Value argv[] = {
-        ObjectOrNullValue(target)
-    };
-    RootedValue trapResult(cx);
-    if (!Invoke(cx, ObjectValue(*handler), trap, ArrayLength(argv), argv, &trapResult))
-        return false;
-
-    // step 10
-    if (trapResult.isPrimitive()) {
-        ReportInvalidTrapResult(cx, proxy, cx->names().enumerate);
-        return false;
-    }
-
-    // step 11
-    objp.set(&trapResult.toObject());
-    return true;
-}
-
 // ES6 (22 May, 2014) 9.5.7 Proxy.[[HasProperty]](P)
 bool
 ScriptedDirectProxyHandler::has(JSContext* cx, HandleObject proxy, HandleId id, bool* bp) const

js/src/proxy/ScriptedDirectProxyHandler.h

@@ -28,7 +28,6 @@ class ScriptedDirectProxyHandler : public BaseProxyHandler {
                                  AutoIdVector& props) const override;
     virtual bool delete_(JSContext* cx, HandleObject proxy, HandleId id,
                          ObjectOpResult& result) const override;
-    virtual bool enumerate(JSContext* cx, HandleObject proxy, MutableHandleObject objp) const override;
 
     /* These two are standard internal methods but aren't implemented to spec yet. */
     virtual bool getPrototype(JSContext* cx, HandleObject proxy,

js/src/tests/ecma_6/Proxy/proxy-for-in.js

@@ -0,0 +1,37 @@
+// Any copyright is dedicated to the Public Domain.
+// http://creativecommons.org/licenses/publicdomain/
+"use strict";
+
+let steps = [];
+
+const object = {
+    __proto__: {
+        "xyz": 42
+    }
+};
+const proxy = new Proxy(object, {
+    ownKeys(target) {
+        steps.push("ownKeys")
+        return ["a", "b"];
+    },
+
+    getOwnPropertyDescriptor(target, property) {
+        steps.push("getOwn-" + property);
+        return {
+            value: undefined,
+            configurable: true,
+            writable: true,
+            enumerable: (property === "a")
+        };
+    }
+});
+
+let iterated = [];
+for (let x in proxy)
+    iterated.push(x);
+
+assertEq(iterated.toString(), "a,xyz");
+assertEq(steps.toString(), "ownKeys,getOwn-a,getOwn-b");
+
+if (typeof reportCompare === "function")
+    reportCompare(true, true);

js/src/tests/ecma_6/Proxy/revoke-as-side-effect.js

@@ -53,16 +53,6 @@ assertThrowsInstanceOf(() => createProxy({a: 5}).a = 0, TypeError);
 assertEq(delete createProxy({}).a, true);
 assertEq(delete createProxy(Object.defineProperty({}, "a", {configurable: false})).a, false);
 
-// [[Enumerate]]
-for (var k in createProxy({})) {
-    // No properties in object.
-    assertEq(true, false);
-}
-for (var k in createProxy({a: 5})) {
-    // Properties in object.
-    assertEq(k, "a");
-}
-
 // [[OwnPropertyKeys]]
 assertEq(Object.getOwnPropertyNames(createProxy({})).length, 0);
 assertEq(Object.getOwnPropertyNames(createProxy({a: 5})).length, 1);

testing/specialpowers/content/specialpowersAPI.js

@@ -294,13 +294,6 @@ SpecialPowersHandler.prototype = {
     return props;
   },
 
-  enumerate(target) {
-    return (function*() {
-      for (let property in this.wrappedObject)
-        yield property;
-    }).call(this);
-  },
-
   preventExtensions(target) {
     throw "Can't call preventExtensions on SpecialPowers wrapped object";
   }