Source code
Revision control
Copy as Markdown
Other Tools
Test Info:
- This WPT test may be referenced by the following Test IDs:
- /webidl/ecmascript-binding/class-string-named-properties-object.window.html - WPT Dashboard Interop Dashboard
"use strict";
const namedPropertiesObject = Object.getPrototypeOf(Window.prototype);
test(() => {
assert_own_property(namedPropertiesObject, Symbol.toStringTag);
const propDesc = Object.getOwnPropertyDescriptor(namedPropertiesObject, Symbol.toStringTag);
assert_equals(propDesc.value, "WindowProperties", "value");
assert_equals(propDesc.configurable, true, "configurable");
assert_equals(propDesc.enumerable, false, "enumerable");
assert_equals(propDesc.writable, false, "writable");
}, "@@toStringTag exists with the appropriate descriptor");
test(() => {
assert_equals(Object.prototype.toString.call(namedPropertiesObject), "[object WindowProperties]");
}, "Object.prototype.toString");
// was no @@toStringTag, it would fall back to a magic class string. Tests for this are present in
// the sibling class-string*.any.js tests. However, the named properties object always fails calls
// to [[DefineOwnProperty]] or [[SetPrototypeOf]] per the Web IDL spec, so there is no way to
// trigger the buggy behavior for it.