// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --harmony-tostring --harmony-proxies
var global = this;
var funs = {
Object: [ Object ],
Function: [ Function ],
Array: [ Array ],
String: [ String ],
Boolean: [ Boolean ],
Number: [ Number ],
Date: [ Date ],
RegExp: [ RegExp ],
Error: [ Error, TypeError, RangeError, SyntaxError, ReferenceError,
EvalError, URIError ]
}
for (f in funs) {
for (i in funs[f]) {
assertEquals("[object " + f + "]",
Object.prototype.toString.call(new funs[f][i]),
funs[f][i]);
assertEquals("[object Function]",
Object.prototype.toString.call(funs[f][i]),
funs[f][i]);
}
}
function testToStringTag(className) {
// Using builtin toStringTags
var obj = {};
obj[Symbol.toStringTag] = className;
assertEquals("[object " + className + "]",
Object.prototype.toString.call(obj));
// Getter throws
obj = {};
Object.defineProperty(obj, Symbol.toStringTag, {
get: function() { throw className; }
});
assertThrowsEquals(function() {
Object.prototype.toString.call(obj);
}, className);
// Getter does not throw
obj = {};
Object.defineProperty(obj, Symbol.toStringTag, {
get: function() { return className; }
});
assertEquals("[object " + className + "]",
Object.prototype.toString.call(obj));
// Custom, non-builtin toStringTags
obj = {};
obj[Symbol.toStringTag] = "X" + className;
assertEquals("[object X" + className + "]",
Object.prototype.toString.call(obj));
// With getter
obj = {};
Object.defineProperty(obj, Symbol.toStringTag, {
get: function() { return "X" + className; }
});
assertEquals("[object X" + className + "]",
Object.prototype.toString.call(obj));
// Undefined toStringTag should return [object className]
var obj = className === "Arguments" ?
(function() { return arguments; })() : new global[className];
obj[Symbol.toStringTag] = undefined;
assertEquals("[object " + className + "]",
Object.prototype.toString.call(obj));
// With getter
var obj = className === "Arguments" ?
(function() { return arguments; })() : new global[className];
Object.defineProperty(obj, Symbol.toStringTag, {
get: function() { return undefined; }
});
assertEquals("[object " + className + "]",
Object.prototype.toString.call(obj));
}
[
"Arguments",
"Array",
"Boolean",
"Date",
"Error",
"Function",
"Number",
"RegExp",
"String"
].forEach(testToStringTag);
function testToStringTagNonString(value) {
var obj = {};
obj[Symbol.toStringTag] = value;
assertEquals("[object Object]", Object.prototype.toString.call(obj));
// With getter
obj = {};
Object.defineProperty(obj, Symbol.toStringTag, {
get: function() { return value; }
});
assertEquals("[object Object]", Object.prototype.toString.call(obj));
}
[
null,
function() {},
[],
{},
/regexp/,
42,
Symbol("sym"),
new Date(),
(function() { return arguments; })(),
true,
new Error("oops"),
new String("str")
].forEach(testToStringTagNonString);
function testObjectToStringPropertyDesc() {
var desc = Object.getOwnPropertyDescriptor(Object.prototype, "toString");
assertTrue(desc.writable);
assertFalse(desc.enumerable);
assertTrue(desc.configurable);
}
testObjectToStringPropertyDesc();
function testObjectToStringOwnNonStringValue() {
var obj = Object.defineProperty({}, Symbol.toStringTag, { value: 1 });
assertEquals("[object Object]", ({}).toString.call(obj));
}
testObjectToStringOwnNonStringValue();
// Proxies
function assertTag(tag, obj) {
assertEquals("[object " + tag + "]", Object.prototype.toString.call(obj));
}
assertTag("Object", new Proxy({}, {}));
assertTag("Array", new Proxy([], {}));
assertTag("Function", new Proxy(() => 42, {}));
assertTag("Foo", new Proxy(() => 42, {get() {return "Foo"}}));
assertTag("Function", new Proxy(() => 42, {get() {return 666}}));
revocable = Proxy.revocable([], {});
revocable.revoke();
assertThrows(() => Object.prototype.toString.call(revocable.proxy), TypeError);
handler = {};
revocable = Proxy.revocable([], handler);
handler.get = () => revocable.revoke();
assertThrows(() => Object.prototype.toString.call(revocable.proxy), TypeError);