diff options
Diffstat (limited to 'js/src/tests/ecma_6/Symbol/as-base-value.js')
-rw-r--r-- | js/src/tests/ecma_6/Symbol/as-base-value.js | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/js/src/tests/ecma_6/Symbol/as-base-value.js b/js/src/tests/ecma_6/Symbol/as-base-value.js new file mode 100644 index 000000000..f0e8400a2 --- /dev/null +++ b/js/src/tests/ecma_6/Symbol/as-base-value.js @@ -0,0 +1,87 @@ +/* Any copyright is dedicated to the Public Domain. + * http://creativecommons.org/licenses/publicdomain/ */ + +// Like other primitives, symbols can be treated as objects, using object-like +// syntax: `symbol.prop` or `symbol[key]`. +// +// In ECMAScript spec jargon, this creates a Reference whose base value is a +// primitive Symbol value. + +var symbols = [ + Symbol(), + Symbol("ponies"), + Symbol.for("sym"), + Symbol.iterator +]; + +// Test accessor property, used below. +var gets, sets; +Object.defineProperty(Symbol.prototype, "prop", { + get: function () { + "use strict"; + gets++; + assertEq(typeof this, "symbol"); + assertEq(this, sym); + return "got"; + }, + set: function (v) { + "use strict"; + sets++; + assertEq(typeof this, "symbol"); + assertEq(this, sym); + assertEq(v, "newvalue"); + } +}); + +for (var sym of symbols) { + assertEq(sym.constructor, Symbol); + + // method on Object.prototype + assertEq(sym.hasOwnProperty("constructor"), false); + assertEq(sym.toLocaleString(), sym.toString()); // once .toString() exists + + // custom method monkeypatched onto Symbol.prototype + Symbol.prototype.nonStrictMethod = function (arg) { + assertEq(arg, "ok"); + assertEq(this instanceof Symbol, true); + assertEq(this.valueOf(), sym); + return 13; + }; + assertEq(sym.nonStrictMethod("ok"), 13); + + // the same, but strict mode + Symbol.prototype.strictMethod = function (arg) { + "use strict"; + assertEq(arg, "ok2"); + assertEq(this, sym); + return 14; + }; + assertEq(sym.strictMethod("ok2"), 14); + + // getter/setter on Symbol.prototype + gets = 0; + sets = 0; + var propname = "prop"; + + assertEq(sym.prop, "got"); + assertEq(gets, 1); + assertEq(sym[propname], "got"); + assertEq(gets, 2); + + assertEq(sym.prop = "newvalue", "newvalue"); + assertEq(sets, 1); + assertEq(sym[propname] = "newvalue", "newvalue"); + assertEq(sets, 2); + + // non-existent property + assertEq(sym.noSuchProp, undefined); + var noSuchPropName = "nonesuch"; + assertEq(sym[noSuchPropName], undefined); + + // non-existent method + assertThrowsInstanceOf(() => sym.noSuchProp(), TypeError); + assertThrowsInstanceOf(() => sym[noSuchPropName](), TypeError); +} + +if (typeof reportCompare === "function") + reportCompare(0, 0); |