jscript: Add Object.isExtensible implementation.

dlls/jscript/object.c

@@ -693,12 +693,34 @@ static HRESULT Object_preventExtensions(script_ctx_t *ctx, vdisp_t *jsthis, WORD
     return S_OK;
 }
 
+static HRESULT Object_isExtensible(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv, jsval_t *r)
+{
+    jsdisp_t *obj;
+
+    if(!argc || !is_object_instance(argv[0]) || !get_object(argv[0])) {
+        WARN("argument is not an object\n");
+        return JS_E_OBJECT_EXPECTED;
+    }
+
+    TRACE("(%s)\n", debugstr_jsval(argv[0]));
+
+    obj = to_jsdisp(get_object(argv[0]));
+    if(!obj) {
+        FIXME("Non-JS object\n");
+        return E_NOTIMPL;
+    }
+
+    if(r) *r = jsval_bool(obj->extensible);
+    return S_OK;
+}
+
 static const builtin_prop_t ObjectConstr_props[] = {
     {L"create",                   Object_create,                      PROPF_ES5|PROPF_METHOD|2},
     {L"defineProperties",         Object_defineProperties,            PROPF_ES5|PROPF_METHOD|2},
     {L"defineProperty",           Object_defineProperty,              PROPF_ES5|PROPF_METHOD|2},
     {L"getOwnPropertyDescriptor", Object_getOwnPropertyDescriptor,    PROPF_ES5|PROPF_METHOD|2},
     {L"getPrototypeOf",           Object_getPrototypeOf,              PROPF_ES5|PROPF_METHOD|1},
+    {L"isExtensible",             Object_isExtensible,                PROPF_ES5|PROPF_METHOD|1},
     {L"keys",                     Object_keys,                        PROPF_ES5|PROPF_METHOD|1},
     {L"preventExtensions",        Object_preventExtensions,           PROPF_ES5|PROPF_METHOD|1},
 };

dlls/mshtml/tests/es5.js

@@ -958,6 +958,8 @@ sync_test("preventExtensions", function() {
 
     r = Object.preventExtensions(o);
     ok(r === o, "r != o");
+    r = Object.isExtensible(o);
+    ok(r === false, "isExtensible(o) returned " + r);
 
     function Constr() {}
     o = Object.preventExtensions(new Constr());
@@ -965,8 +967,21 @@ sync_test("preventExtensions", function() {
     ok(o.prop === 1, "o.prop = " + o.prop);
     o.prop = 2;
     ok(o.prop === 1, "o.prop = " + o.prop);
+    r = Object.isExtensible(o);
+    ok(r === false, "isExtensible(o) returned " + r);
+
+    r = Object.isExtensible({});
+    ok(r === true, "isExtensible(o) returned " + r);
+
+    try {
+        Object.isExtensible(1);
+        ok(false, "exception expected");
+    }catch(e) {
+        ok(e.name === "TypeError", "got " + e.name + " exception");
+    }
 
     ok(Object.preventExtensions.length === 1, "Object.preventExtensions.length = " + Object.preventExtensions.length);
+    ok(Object.isExtensible.length === 1, "Object.isExtensible.length = " + Object.isExtensible.length);
 });
 
 sync_test("head_setter", function() {