1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/js/src/tests/supporting/testBuiltInObject.js Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,124 @@
1.4 +// Copyright 2012 Mozilla Corporation. All rights reserved.
1.5 +// This code is governed by the BSD license found in the LICENSE file.
1.6 +
1.7 +/**
1.8 + * @description Tests that obj meets the requirements for built-in objects
1.9 + * defined by the introduction of chapter 15 of the ECMAScript Language Specification.
1.10 + * @param {Object} obj the object to be tested.
1.11 + * @param {boolean} isFunction whether the specification describes obj as a function.
1.12 + * @param {boolean} isConstructor whether the specification describes obj as a constructor.
1.13 + * @param {String[]} properties an array with the names of the built-in properties of obj,
1.14 + * excluding length, prototype, or properties with non-default attributes.
1.15 + * @param {number} length for functions only: the length specified for the function
1.16 + * or derived from the argument list.
1.17 + * @author Norbert Lindenberg
1.18 + */
1.19 +
1.20 +function testBuiltInObject(obj, isFunction, isConstructor, properties, length) {
1.21 +
1.22 + if (obj === undefined) {
1.23 + $ERROR("Object being tested is undefined.");
1.24 + }
1.25 +
1.26 + var objString = Object.prototype.toString.call(obj);
1.27 + if (isFunction) {
1.28 + if (objString !== "[object Function]") {
1.29 + $ERROR("The [[Class]] internal property of a built-in function must be " +
1.30 + "\"Function\", but toString() returns " + objString);
1.31 + }
1.32 + } else {
1.33 + if (objString !== "[object Object]") {
1.34 + $ERROR("The [[Class]] internal property of a built-in non-function object must be " +
1.35 + "\"Object\", but toString() returns " + objString);
1.36 + }
1.37 + }
1.38 +
1.39 + if (!Object.isExtensible(obj)) {
1.40 + $ERROR("Built-in objects must be extensible.");
1.41 + }
1.42 +
1.43 + if (isFunction && Object.getPrototypeOf(obj) !== Function.prototype) {
1.44 + $ERROR("Built-in functions must have Function.prototype as their prototype.");
1.45 + }
1.46 +
1.47 + if (isConstructor && Object.getPrototypeOf(obj.prototype) !== Object.prototype) {
1.48 + $ERROR("Built-in prototype objects must have Object.prototype as their prototype.");
1.49 + }
1.50 +
1.51 + // verification of the absence of the [[Construct]] internal property has
1.52 + // been moved to the end of the test
1.53 +
1.54 + // verification of the absence of the prototype property has
1.55 + // been moved to the end of the test
1.56 +
1.57 + if (isFunction) {
1.58 +
1.59 + if (typeof obj.length !== "number" || obj.length !== Math.floor(obj.length)) {
1.60 + $ERROR("Built-in functions must have a length property with an integer value.");
1.61 + }
1.62 +
1.63 + if (obj.length !== length) {
1.64 + $ERROR("Function's length property doesn't have specified value; expected " +
1.65 + length + ", got " + obj.length + ".");
1.66 + }
1.67 +
1.68 + var desc = Object.getOwnPropertyDescriptor(obj, "length");
1.69 + if (desc.writable) {
1.70 + $ERROR("The length property of a built-in function must not be writable.");
1.71 + }
1.72 + if (desc.enumerable) {
1.73 + $ERROR("The length property of a built-in function must not be enumerable.");
1.74 + }
1.75 + if (desc.configurable) {
1.76 + $ERROR("The length property of a built-in function must not be configurable.");
1.77 + }
1.78 + }
1.79 +
1.80 + properties.forEach(function(prop) {
1.81 + var desc = Object.getOwnPropertyDescriptor(obj, prop);
1.82 + if (desc === undefined) {
1.83 + $ERROR("Missing property " + prop + ".");
1.84 + }
1.85 + // accessor properties don't have writable attribute
1.86 + if (desc.hasOwnProperty("writable") && !desc.writable) {
1.87 + $ERROR("The " + prop + " property of this built-in function must be writable.");
1.88 + }
1.89 + if (desc.enumerable) {
1.90 + $ERROR("The " + prop + " property of this built-in function must not be enumerable.");
1.91 + }
1.92 + if (!desc.configurable) {
1.93 + $ERROR("The " + prop + " property of this built-in function must be configurable.");
1.94 + }
1.95 + });
1.96 +
1.97 + // The remaining sections have been moved to the end of the test because
1.98 + // unbound non-constructor functions written in JavaScript cannot possibly
1.99 + // pass them, and we still want to test JavaScript implementations as much
1.100 + // as possible.
1.101 +
1.102 + var exception;
1.103 + if (isFunction && !isConstructor) {
1.104 + // this is not a complete test for the presence of [[Construct]]:
1.105 + // if it's absent, the exception must be thrown, but it may also
1.106 + // be thrown if it's present and just has preconditions related to
1.107 + // arguments or the this value that this statement doesn't meet.
1.108 + try {
1.109 + /*jshint newcap:false*/
1.110 + var instance = new obj();
1.111 + } catch (e) {
1.112 + exception = e;
1.113 + }
1.114 + if (exception === undefined || exception.name !== "TypeError") {
1.115 + $ERROR("Built-in functions that aren't constructors must throw TypeError when " +
1.116 + "used in a \"new\" statement.");
1.117 + }
1.118 + }
1.119 +
1.120 + if (isFunction && !isConstructor && obj.hasOwnProperty("prototype")) {
1.121 + $ERROR("Built-in functions that aren't constructors must not have a prototype property.");
1.122 + }
1.123 +
1.124 + // passed the complete test!
1.125 + return true;
1.126 +}
1.127 +
