/* Any copyright is dedicated to the Public Domain. * http://creativecommons.org/publicdomain/zero/1.0/ */ /** * This file tests the method defineLazyProxy from XPCOMUtils.jsm. */ const {XPCOMUtils} = ChromeUtils.import("resource://gre/modules/XPCOMUtils.jsm"); add_task(function test_lazy_proxy() { let tmp = {}; let realObject = { "prop1": "value1", "prop2": "value2", }; let evaluated = false; let untrapCalled = false; let lazyProxy = XPCOMUtils.defineLazyProxy( tmp, "myLazyProxy", // Initiliazer function function init() { evaluated = true; return realObject; }, // Stub properties { "prop1": "stub" }, // Untrap callback function untrapCallback(obj) { Assert.equal(obj, realObject, "The underlying object can be obtained in the untrap callback"); untrapCalled = true; } ); // Check that the proxy returned and the one // defined in tmp are the same. // // Note: Assert.strictEqual can't be used here // because it wants to stringify the two objects // compared, which defeats the lazy proxy. Assert.ok(lazyProxy === tmp.myLazyProxy, "Return value and object defined are the same"); Assert.ok(Cu.isProxy(lazyProxy), "Returned value is in fact a proxy"); // Check that just using the proxy above didn't // trigger the lazy getter evaluation. Assert.ok(!evaluated, "The lazy proxy hasn't been evaluated yet"); Assert.ok(!untrapCalled, "The untrap callback hasn't been called yet"); // Accessing a stubbed property returns the stub // value and doesn't trigger evaluation. Assert.equal(lazyProxy.prop1, "stub", "Accessing a stubbed property returns the stubbed value"); Assert.ok(!evaluated, "The access to the stubbed property above didn't evaluate the lazy proxy"); Assert.ok(!untrapCalled, "The untrap callback hasn't been called yet"); // Now the access to another property will trigger // the evaluation, as expected. Assert.equal(lazyProxy.prop2, "value2", "Property access is correctly forwarded to the underlying object"); Assert.ok(evaluated, "Accessing a non-stubbed property triggered the proxy evaluation"); Assert.ok(untrapCalled, "The untrap callback was called"); // The value of prop1 is now the real value and not the stub value. Assert.equal(lazyProxy.prop1, "value1", "The value of prop1 is now the real value and not the stub one"); }); add_task(function test_module_version() { // Test that passing a string instead of an initialization function // makes this behave like a lazy module getter. const NET_UTIL_URI = "resource://gre/modules/NetUtil.jsm"; let underlyingObject; Cu.unload(NET_UTIL_URI); let lazyProxy = XPCOMUtils.defineLazyProxy( null, "NetUtil", NET_UTIL_URI, null, /* no stubs */ function untrapCallback(object) { underlyingObject = object; } ); Assert.ok(!Cu.isModuleLoaded(NET_UTIL_URI), "The NetUtil module was not loaded by the lazy proxy definition"); // Access the object, which will evaluate the proxy. lazyProxy.foo = "bar"; // Module was loaded. Assert.ok(Cu.isModuleLoaded(NET_UTIL_URI), "The NetUtil module was loaded"); let { NetUtil } = ChromeUtils.import(NET_UTIL_URI, {}); // Avoids a gigantic stringification in the logs. Assert.ok(NetUtil === underlyingObject, "The module loaded is the same as the one directly obtained by ChromeUtils.import"); // Proxy correctly passed the setter to the underlying object. Assert.equal(NetUtil.foo, "bar", "Proxy correctly passed the setter to the underlying object"); delete lazyProxy.foo; // Proxy correctly passed the delete operation to the underlying object. Assert.ok(!NetUtil.hasOwnProperty("foo"), "Proxy correctly passed the delete operation to the underlying object"); });