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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Portions of this file are originally from narwhal.js (http://narwhaljs.org)
+// Copyright (c) 2009 Thomas Robinson <280north.com>
+// MIT license: http://opensource.org/licenses/MIT
+
+// Used only to cause test failures.
+
+var pSlice = Array.prototype.slice;
+
+export var ObjectUtils = {
+ /**
+ * This tests objects & values for deep equality.
+ *
+ * We check using the most exact approximation of equality between two objects
+ * to keep the chance of false positives to a minimum.
+ * `JSON.stringify` is not designed to be used for this purpose; objects may
+ * have ambiguous `toJSON()` implementations that would influence the test.
+ *
+ * @param a (mixed) Object or value to be compared.
+ * @param b (mixed) Object or value to be compared.
+ * @return Boolean Whether the objects are deep equal.
+ */
+ deepEqual(a, b) {
+ return _deepEqual(a, b);
+ },
+
+ /**
+ * A thin wrapper on an object, designed to prevent client code from
+ * accessing non-existent properties because of typos.
+ *
+ * // Without `strict`
+ * let foo = { myProperty: 1 };
+ * foo.MyProperty; // undefined
+ *
+ * // With `strict`
+ * let strictFoo = ObjectUtils.strict(foo);
+ * strictFoo.myProperty; // 1
+ * strictFoo.MyProperty; // TypeError: No such property "MyProperty"
+ *
+ * Note that `strict` has no effect in non-DEBUG mode.
+ */
+ strict(obj) {
+ return _strict(obj);
+ },
+
+ /**
+ * Returns `true` if `obj` is an array without elements, an object without
+ * enumerable properties, or a falsy primitive; `false` otherwise.
+ */
+ isEmpty(obj) {
+ if (!obj) {
+ return true;
+ }
+ if (typeof obj != "object") {
+ return false;
+ }
+ if (Array.isArray(obj)) {
+ return !obj.length;
+ }
+ for (let key in obj) {
+ return false;
+ }
+ return true;
+ },
+};
+
+// ... Start of previously MIT-licensed code.
+// This deepEqual implementation is originally from narwhal.js (http://narwhaljs.org)
+// Copyright (c) 2009 Thomas Robinson <280north.com>
+// MIT license: http://opensource.org/licenses/MIT
+
+function _deepEqual(a, b) {
+ // The numbering below refers to sections in the CommonJS spec.
+
+ // 7.1 All identical values are equivalent, as determined by ===.
+ if (a === b) {
+ return true;
+ // 7.2 If the b value is a Date object, the a value is
+ // equivalent if it is also a Date object that refers to the same time.
+ }
+ let aIsDate = instanceOf(a, "Date");
+ let bIsDate = instanceOf(b, "Date");
+ if (aIsDate || bIsDate) {
+ if (!aIsDate || !bIsDate) {
+ return false;
+ }
+ if (isNaN(a.getTime()) && isNaN(b.getTime())) {
+ return true;
+ }
+ return a.getTime() === b.getTime();
+ // 7.3 If the b value is a RegExp object, the a value is
+ // equivalent if it is also a RegExp object with the same source and
+ // properties (`global`, `multiline`, `lastIndex`, `ignoreCase`).
+ }
+ let aIsRegExp = instanceOf(a, "RegExp");
+ let bIsRegExp = instanceOf(b, "RegExp");
+ if (aIsRegExp || bIsRegExp) {
+ return (
+ aIsRegExp &&
+ bIsRegExp &&
+ a.source === b.source &&
+ a.global === b.global &&
+ a.multiline === b.multiline &&
+ a.lastIndex === b.lastIndex &&
+ a.ignoreCase === b.ignoreCase
+ );
+ // 7.4 Other pairs that do not both pass typeof value == "object",
+ // equivalence is determined by ==.
+ }
+ if (typeof a != "object" || typeof b != "object") {
+ return a == b;
+ }
+ // 7.5 For all other Object pairs, including Array objects, equivalence is
+ // determined by having the same number of owned properties (as verified
+ // with Object.prototype.hasOwnProperty.call), the same set of keys
+ // (although not necessarily the same order), equivalent values for every
+ // corresponding key, and an identical 'prototype' property. Note: this
+ // accounts for both named and indexed properties on Arrays.
+ return objEquiv(a, b);
+}
+
+function instanceOf(object, type) {
+ return Object.prototype.toString.call(object) == "[object " + type + "]";
+}
+
+function isUndefinedOrNull(value) {
+ return value === null || value === undefined;
+}
+
+function isArguments(object) {
+ return instanceOf(object, "Arguments");
+}
+
+function objEquiv(a, b) {
+ if (isUndefinedOrNull(a) || isUndefinedOrNull(b)) {
+ return false;
+ }
+ // An identical 'prototype' property.
+ if ((a.prototype || undefined) != (b.prototype || undefined)) {
+ return false;
+ }
+ // Object.keys may be broken through screwy arguments passing. Converting to
+ // an array solves the problem.
+ if (isArguments(a)) {
+ if (!isArguments(b)) {
+ return false;
+ }
+ a = pSlice.call(a);
+ b = pSlice.call(b);
+ return _deepEqual(a, b);
+ }
+ let ka, kb;
+ try {
+ ka = Object.keys(a);
+ kb = Object.keys(b);
+ } catch (e) {
+ // Happens when one is a string literal and the other isn't
+ return false;
+ }
+ // Having the same number of owned properties (keys incorporates
+ // hasOwnProperty)
+ if (ka.length != kb.length) {
+ return false;
+ }
+ // The same set of keys (although not necessarily the same order),
+ ka.sort();
+ kb.sort();
+ // Equivalent values for every corresponding key, and possibly expensive deep
+ // test
+ for (let key of ka) {
+ if (!_deepEqual(a[key], b[key])) {
+ return false;
+ }
+ }
+ return true;
+}
+
+// ... End of previously MIT-licensed code.
+
+function _strict(obj) {
+ if (typeof obj != "object") {
+ throw new TypeError("Expected an object");
+ }
+
+ return new Proxy(obj, {
+ get(target, name) {
+ if (name in obj) {
+ return obj[name];
+ }
+
+ let error = new TypeError(`No such property: "${name}"`);
+ Promise.reject(error); // Cause an xpcshell/mochitest failure.
+ throw error;
+ },
+ });
+}