diff options
Diffstat (limited to 'js/src/tests/ecma_6/Reflect/setPrototypeOf.js')
-rw-r--r-- | js/src/tests/ecma_6/Reflect/setPrototypeOf.js | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/js/src/tests/ecma_6/Reflect/setPrototypeOf.js b/js/src/tests/ecma_6/Reflect/setPrototypeOf.js new file mode 100644 index 000000000..ed7857a02 --- /dev/null +++ b/js/src/tests/ecma_6/Reflect/setPrototypeOf.js @@ -0,0 +1,72 @@ +/* Any copyright is dedicated to the Public Domain. + * http://creativecommons.org/licenses/publicdomain/ */ + +// Reflect.setPrototypeOf changes an object's [[Prototype]]. +var obj = {}; +assertEq(Object.getPrototypeOf(obj), Object.prototype); +var proto = {}; +assertEq(Reflect.setPrototypeOf(obj, proto), true); +assertEq(Object.getPrototypeOf(obj), proto); + +// It can change an object's [[Prototype]] to null. +obj = {}; +assertEq(Reflect.setPrototypeOf(obj, null), true); +assertEq(Object.getPrototypeOf(obj), null); + +// The proto argument is required too. +obj = {}; +assertThrowsInstanceOf(() => Reflect.setPrototypeOf(obj), TypeError); + +// The proto argument must be either null or an object. +for (proto of [undefined, false, 0, 1.6, "that", Symbol.iterator]) { + assertThrowsInstanceOf(() => Reflect.setPrototypeOf(obj, proto), TypeError); +} + +// Return false if the target isn't extensible. +proto = {}; +obj = Object.preventExtensions(Object.create(proto)); +assertEq(Reflect.setPrototypeOf(obj, {}), false); +assertEq(Reflect.setPrototypeOf(obj, null), false); +assertEq(Reflect.setPrototypeOf(obj, proto), true); // except if not changing anything + +// Return false rather than create a [[Prototype]] cycle. +obj = {}; +assertEq(Reflect.setPrototypeOf(obj, obj), false); + +// Don't create a [[Prototype]] cycle involving 2 objects. +obj = Object.create(proto); +assertEq(Reflect.setPrototypeOf(proto, obj), false); + +// Don't create a longish [[Prototype]] cycle. +for (var i = 0; i < 256; i++) + obj = Object.create(obj); +assertEq(Reflect.setPrototypeOf(proto, obj), false); + +// The spec claims we should allow creating cycles involving proxies. (The +// cycle check quietly exits on encountering the proxy.) +obj = {}; +var proxy = new Proxy(Object.create(obj), {}); + +assertEq(Reflect.setPrototypeOf(obj, proxy), true); +assertEq(Reflect.getPrototypeOf(obj), proxy); +assertEq(Reflect.getPrototypeOf(proxy), obj); + +// If a proxy handler returns a false-y value, return false. +var hits = 0; +proto = {name: "proto"}; +obj = {name: "obj"}; +proxy = new Proxy(obj, { + setPrototypeOf(t, p) { + assertEq(t, obj); + assertEq(p, proto); + hits++; + return 0; + } +}); + +assertEq(Reflect.setPrototypeOf(proxy, proto), false); +assertEq(hits, 1); + +// For more Reflect.setPrototypeOf tests, see target.js. + +reportCompare(0, 0); |