The Tor Browser / file revision

 /* -*- Mode: JavaScript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

 /* vim:set ts=2 sw=2 sts=2 et: */

 /* 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/. */

 /*

  * This file contains common code that is loaded before each test file(s).

  * See http://developer.mozilla.org/en/docs/Writing_xpcshell-based_unit_tests

  * for more information.

  */

 var _quit = false;

 var _passed = true;

 var _tests_pending = 0;

 var _passedChecks = 0, _falsePassedChecks = 0;

 var _todoChecks = 0;

 var _cleanupFunctions = [];

 var _pendingTimers = [];

 var _profileInitialized = false;

 let _Promise = Components.utils.import("resource://gre/modules/Promise.jsm", this).Promise;

 let _log = function (action, params) {

   if (typeof _XPCSHELL_PROCESS != "undefined") {

     params.process = _XPCSHELL_PROCESS;

   }

   params.action = action;

   params._time = Date.now();

   dump("\n" + JSON.stringify(params) + "\n");

 }

 function _dump(str) {

   let start = /^TEST-/.test(str) ? "\n" : "";

   if (typeof _XPCSHELL_PROCESS == "undefined") {

     dump(start + str);

   } else {

     dump(start + _XPCSHELL_PROCESS + ": " + str);

   }

 }

 // Disable automatic network detection, so tests work correctly when

 // not connected to a network.

 let (ios = Components.classes["@mozilla.org/network/io-service;1"]

            .getService(Components.interfaces.nsIIOService2)) {

   ios.manageOfflineStatus = false;

   ios.offline = false;

 }

 // Determine if we're running on parent or child

 let runningInParent = true;

 try {

   runningInParent = Components.classes["@mozilla.org/xre/runtime;1"].

                     getService(Components.interfaces.nsIXULRuntime).processType

                     == Components.interfaces.nsIXULRuntime.PROCESS_TYPE_DEFAULT;

 } 

 catch (e) { }

 // Only if building of places is enabled.

 if (runningInParent &&

     "mozIAsyncHistory" in Components.interfaces) {

   // Ensure places history is enabled for xpcshell-tests as some non-FF

   // apps disable it.

   let (prefs = Components.classes["@mozilla.org/preferences-service;1"]

                .getService(Components.interfaces.nsIPrefBranch)) {

     prefs.setBoolPref("places.history.enabled", true);

   };

 }

 try {

   if (runningInParent) {

     let prefs = Components.classes["@mozilla.org/preferences-service;1"]

                 .getService(Components.interfaces.nsIPrefBranch);

     // disable necko IPC security checks for xpcshell, as they lack the

     // docshells needed to pass them

     prefs.setBoolPref("network.disable.ipc.security", true);

     // Disable IPv6 lookups for 'localhost' on windows.

     if ("@mozilla.org/windows-registry-key;1" in Components.classes) {

       prefs.setCharPref("network.dns.ipv4OnlyDomains", "localhost");

     }

   }

 }

 catch (e) { }

 // Configure crash reporting, if possible

 // We rely on the Python harness to set MOZ_CRASHREPORTER,

 // MOZ_CRASHREPORTER_NO_REPORT, and handle checking for minidumps.

 // Note that if we're in a child process, we don't want to init the

 // crashreporter component.

 try {

   if (runningInParent &&

       "@mozilla.org/toolkit/crash-reporter;1" in Components.classes) {

     let (crashReporter =

           Components.classes["@mozilla.org/toolkit/crash-reporter;1"]

           .getService(Components.interfaces.nsICrashReporter)) {

       crashReporter.UpdateCrashEventsDir();

       crashReporter.minidumpPath = do_get_minidumpdir();

     }

   }

 }

 catch (e) { }

 /**

  * Date.now() is not necessarily monotonically increasing (insert sob story

  * about times not being the right tool to use for measuring intervals of time,

  * robarnold can tell all), so be wary of error by erring by at least

  * _timerFuzz ms.

  */

 const _timerFuzz = 15;

 function _Timer(func, delay) {

   delay = Number(delay);

   if (delay < 0)

     do_throw("do_timeout() delay must be nonnegative");

   if (typeof func !== "function")

     do_throw("string callbacks no longer accepted; use a function!");

   this._func = func;

   this._start = Date.now();

   this._delay = delay;

   var timer = Components.classes["@mozilla.org/timer;1"]

                         .createInstance(Components.interfaces.nsITimer);

   timer.initWithCallback(this, delay + _timerFuzz, timer.TYPE_ONE_SHOT);

   // Keep timer alive until it fires

   _pendingTimers.push(timer);

 }

 _Timer.prototype = {

   QueryInterface: function(iid) {

     if (iid.equals(Components.interfaces.nsITimerCallback) ||

         iid.equals(Components.interfaces.nsISupports))

       return this;

     throw Components.results.NS_ERROR_NO_INTERFACE;

   },

   notify: function(timer) {

     _pendingTimers.splice(_pendingTimers.indexOf(timer), 1);

     // The current nsITimer implementation can undershoot, but even if it

     // couldn't, paranoia is probably a virtue here given the potential for

     // random orange on tinderboxen.

     var end = Date.now();

     var elapsed = end - this._start;

     if (elapsed >= this._delay) {

       try {

         this._func.call(null);

       } catch (e) {

         do_throw("exception thrown from do_timeout callback: " + e);

       }

       return;

     }

     // Timer undershot, retry with a little overshoot to try to avoid more

     // undershoots.

     var newDelay = this._delay - elapsed;

     do_timeout(newDelay, this._func);

   }

 };

 function _do_main() {

   if (_quit)

     return;

   _log("test_info",

        {_message: "TEST-INFO | (xpcshell/head.js) | running event loop\n"});

   var thr = Components.classes["@mozilla.org/thread-manager;1"]

                       .getService().currentThread;

   while (!_quit)

     thr.processNextEvent(true);

   while (thr.hasPendingEvents())

     thr.processNextEvent(true);

 }

 function _do_quit() {

   _log("test_info",

        {_message: "TEST-INFO | (xpcshell/head.js) | exiting test\n"});

   _Promise.Debugging.flushUncaughtErrors();

   _quit = true;

 }

 function _format_exception_stack(stack) {

   if (typeof stack == "object" && stack.caller) {

     let frame = stack;

     let strStack = "";

     while (frame != null) {

       strStack += frame + "\n";

       frame = frame.caller;

     }

     stack = strStack;

   }

   // frame is of the form "fname@file:line"

   let frame_regexp = new RegExp("(.*)@(.*):(\\d*)", "g");

   return stack.split("\n").reduce(function(stack_msg, frame) {

     if (frame) {

       let parts = frame_regexp.exec(frame);

       if (parts) {

         let [ _, func, file, line ] = parts;

         return stack_msg + "JS frame :: " + file + " :: " +

           (func || "anonymous") + " :: line " + line + "\n";

       }

       else { /* Could be a -e (command line string) style location. */

         return stack_msg + "JS frame :: " + frame + "\n";

       }

     }

     return stack_msg;

   }, "");

 }

 /**

  * Overrides idleService with a mock.  Idle is commonly used for maintenance

  * tasks, thus if a test uses a service that requires the idle service, it will

  * start handling them.

  * This behaviour would cause random failures and slowdown tests execution,

  * for example by running database vacuum or cleanups for each test.

  *

  * @note Idle service is overridden by default.  If a test requires it, it will

  *       have to call do_get_idle() function at least once before use.

  */

 var _fakeIdleService = {

   get registrar() {

     delete this.registrar;

     return this.registrar =

       Components.manager.QueryInterface(Components.interfaces.nsIComponentRegistrar);

   },

   contractID: "@mozilla.org/widget/idleservice;1",

   get CID() this.registrar.contractIDToCID(this.contractID),

   activate: function FIS_activate()

   {

     if (!this.originalFactory) {

       // Save original factory.

       this.originalFactory =

         Components.manager.getClassObject(Components.classes[this.contractID],

                                           Components.interfaces.nsIFactory);

       // Unregister original factory.

       this.registrar.unregisterFactory(this.CID, this.originalFactory);

       // Replace with the mock.

       this.registrar.registerFactory(this.CID, "Fake Idle Service",

                                      this.contractID, this.factory

       );

     }

   },

   deactivate: function FIS_deactivate()

   {

     if (this.originalFactory) {

       // Unregister the mock.

       this.registrar.unregisterFactory(this.CID, this.factory);

       // Restore original factory.

       this.registrar.registerFactory(this.CID, "Idle Service",

                                      this.contractID, this.originalFactory);

       delete this.originalFactory;

     }

   },

   factory: {

     // nsIFactory

     createInstance: function (aOuter, aIID)

     {

       if (aOuter) {

         throw Components.results.NS_ERROR_NO_AGGREGATION;

       }

       return _fakeIdleService.QueryInterface(aIID);

     },

     lockFactory: function (aLock) {

       throw Components.results.NS_ERROR_NOT_IMPLEMENTED;

     },

     QueryInterface: function(aIID) {

       if (aIID.equals(Components.interfaces.nsIFactory) ||

           aIID.equals(Components.interfaces.nsISupports)) {

         return this;

       }

       throw Components.results.NS_ERROR_NO_INTERFACE;

     }

   },

   // nsIIdleService

   get idleTime() 0,

   addIdleObserver: function () {},

   removeIdleObserver: function () {},

   QueryInterface: function(aIID) {

     // Useful for testing purposes, see test_get_idle.js.

     if (aIID.equals(Components.interfaces.nsIFactory)) {

       return this.factory;

     }

     if (aIID.equals(Components.interfaces.nsIIdleService) ||

         aIID.equals(Components.interfaces.nsISupports)) {

       return this;

     }

     throw Components.results.NS_ERROR_NO_INTERFACE;

   }

 }

 /**

  * Restores the idle service factory if needed and returns the service's handle.

  * @return A handle to the idle service.

  */

 function do_get_idle() {

   _fakeIdleService.deactivate();

   return Components.classes[_fakeIdleService.contractID]

                    .getService(Components.interfaces.nsIIdleService);

 }

 // Map resource://test/ to current working directory and

 // resource://testing-common/ to the shared test modules directory.

 function _register_protocol_handlers() {

   let (ios = Components.classes["@mozilla.org/network/io-service;1"]

              .getService(Components.interfaces.nsIIOService)) {

     let protocolHandler =

       ios.getProtocolHandler("resource")

          .QueryInterface(Components.interfaces.nsIResProtocolHandler);

     let curDirURI = ios.newFileURI(do_get_cwd());

     protocolHandler.setSubstitution("test", curDirURI);

     if (this._TESTING_MODULES_DIR) {

       let modulesFile = Components.classes["@mozilla.org/file/local;1"].

                         createInstance(Components.interfaces.nsILocalFile);

       modulesFile.initWithPath(_TESTING_MODULES_DIR);

       if (!modulesFile.exists()) {

         throw new Error("Specified modules directory does not exist: " +

                         _TESTING_MODULES_DIR);

       }

       if (!modulesFile.isDirectory()) {

         throw new Error("Specified modules directory is not a directory: " +

                         _TESTING_MODULES_DIR);

       }

       let modulesURI = ios.newFileURI(modulesFile);

       protocolHandler.setSubstitution("testing-common", modulesURI);

     }

   }

 }

 function _execute_test() {

   _register_protocol_handlers();

   // Override idle service by default.

   // Call do_get_idle() to restore the factory and get the service.

   _fakeIdleService.activate();

   _Promise.Debugging.clearUncaughtErrorObservers();

   _Promise.Debugging.addUncaughtErrorObserver(function observer({message, date, fileName, stack, lineNumber}) {

     let text = "Once bug 976205 has landed, THIS ERROR WILL CAUSE A TEST FAILURE.\n" +

         " A promise chain failed to handle a rejection: " +

         message + " - rejection date: " + date;

     _log_message_with_stack("test_known_fail",

                             text, stack, fileName);

   });

   // _HEAD_FILES is dynamically defined by <runxpcshelltests.py>.

   _load_files(_HEAD_FILES);

   // _TEST_FILE is dynamically defined by <runxpcshelltests.py>.

   _load_files(_TEST_FILE);

   // Support a common assertion library, Assert.jsm.

   let Assert = Components.utils.import("resource://testing-common/Assert.jsm", null).Assert;

   // Pass a custom report function for xpcshell-test style reporting.

   let assertImpl = new Assert(function(err, message, stack) {

     if (err) {

       do_report_result(false, err.message, err.stack);

     } else {

       do_report_result(true, message, stack);

     }

   });

   // Allow Assert.jsm methods to be tacked to the current scope.

   this.export_assertions = function() {

     for (let func in assertImpl) {

       this[func] = assertImpl[func].bind(assertImpl);

     }

   };

   this.Assert = assertImpl;

   try {

     do_test_pending("MAIN run_test");

     run_test();

     do_test_finished("MAIN run_test");

     _do_main();

   } catch (e) {

     _passed = false;

     // do_check failures are already logged and set _quit to true and throw

     // NS_ERROR_ABORT. If both of those are true it is likely this exception

     // has already been logged so there is no need to log it again. It's

     // possible that this will mask an NS_ERROR_ABORT that happens after a

     // do_check failure though.

     if (!_quit || e != Components.results.NS_ERROR_ABORT) {

       let msgObject = {};

       if (e.fileName) {

         msgObject.source_file = e.fileName;

         if (e.lineNumber) {

           msgObject.line_number = e.lineNumber;

         }

       } else {

         msgObject.source_file = "xpcshell/head.js";

       }

       msgObject.diagnostic = _exception_message(e);

       if (e.stack) {

         msgObject.diagnostic += " - See following stack:\n";

         msgObject.stack = _format_exception_stack(e.stack);

       }

       _log("test_unexpected_fail", msgObject);

     }

   }

   // _TAIL_FILES is dynamically defined by <runxpcshelltests.py>.

   _load_files(_TAIL_FILES);

   // Execute all of our cleanup functions.

   let reportCleanupError = function(ex) {

     let stack, filename;

     if (ex && typeof ex == "object" && "stack" in ex) {

       stack = ex.stack;

     } else {

       stack = Components.stack.caller;

     }

     if (stack instanceof Components.interfaces.nsIStackFrame) {

       filename = stack.filename;

     } else if (ex.fileName) {

       filename = ex.fileName;

     }

     _log_message_with_stack("test_unexpected_fail",

                             ex, stack, filename);

   };

   let func;

   while ((func = _cleanupFunctions.pop())) {

     let result;

     try {

       result = func();

     } catch (ex) {

       reportCleanupError(ex);

       continue;

     }

     if (result && typeof result == "object"

         && "then" in result && typeof result.then == "function") {

       // This is a promise, wait until it is satisfied before proceeding

       let complete = false;

       let promise = result.then(null, reportCleanupError);

       promise = promise.then(() => complete = true);

       let thr = Components.classes["@mozilla.org/thread-manager;1"]

                   .getService().currentThread;

       while (!complete) {

         thr.processNextEvent(true);

       }

     }

   }

   // Restore idle service to avoid leaks.

   _fakeIdleService.deactivate();

   if (!_passed)

     return;

   var truePassedChecks = _passedChecks - _falsePassedChecks;

   if (truePassedChecks > 0) {

     _log("test_pass",

          {_message: "TEST-PASS | (xpcshell/head.js) | " + truePassedChecks + " (+ " +

                     _falsePassedChecks + ") check(s) passed\n",

           source_file: _TEST_FILE,

           passed_checks: truePassedChecks});

     _log("test_info",

          {_message: "TEST-INFO | (xpcshell/head.js) | " + _todoChecks +

                     " check(s) todo\n",

           source_file: _TEST_FILE,

           todo_checks: _todoChecks});

   } else {

     // ToDo: switch to TEST-UNEXPECTED-FAIL when all tests have been updated. (Bug 496443)

     _log("test_info",

          {_message: "TEST-INFO | (xpcshell/head.js) | No (+ " + _falsePassedChecks +

                     ") checks actually run\n",

          source_file: _TEST_FILE});

   }

 }

 /**

  * Loads files.

  *

  * @param aFiles Array of files to load.

  */

 function _load_files(aFiles) {

   function loadTailFile(element, index, array) {

     try {

       load(element);

     } catch (e if e instanceof SyntaxError) {

       _log("javascript_error",

            {_message: "TEST-UNEXPECTED-FAIL | (xpcshell/head.js) | Source file " + element + " contains SyntaxError",

             diagnostic: _exception_message(e),

             source_file: element,

             stack: _format_exception_stack(e.stack)});

     } catch (e) {

       _log("javascript_error",

            {_message: "TEST-UNEXPECTED-FAIL | (xpcshell/head.js) | Source file " + element + " contains an error",

             diagnostic: _exception_message(e),

             source_file: element,

             stack: _format_exception_stack(e.stack)});

     }

   }

   aFiles.forEach(loadTailFile);

 }

 function _wrap_with_quotes_if_necessary(val) {

   return typeof val == "string" ? '"' + val + '"' : val;

 }

 /************** Functions to be used from the tests **************/

 /**

  * Prints a message to the output log.

  */

 function do_print(msg) {

   var caller_stack = Components.stack.caller;

   msg = _wrap_with_quotes_if_necessary(msg);

   _log("test_info",

        {source_file: caller_stack.filename,

         diagnostic: msg});

 }

 /**

  * Calls the given function at least the specified number of milliseconds later.

  * The callback will not undershoot the given time, but it might overshoot --

  * don't expect precision!

  *

  * @param delay : uint

  *   the number of milliseconds to delay

  * @param callback : function() : void

  *   the function to call

  */

 function do_timeout(delay, func) {

   new _Timer(func, Number(delay));

 }

 function do_execute_soon(callback, aName) {

   let funcName = (aName ? aName : callback.name);

   do_test_pending(funcName);

   var tm = Components.classes["@mozilla.org/thread-manager;1"]

                      .getService(Components.interfaces.nsIThreadManager);

   tm.mainThread.dispatch({

     run: function() {

       try {

         callback();

       } catch (e) {

         // do_check failures are already logged and set _quit to true and throw

         // NS_ERROR_ABORT. If both of those are true it is likely this exception

         // has already been logged so there is no need to log it again. It's

         // possible that this will mask an NS_ERROR_ABORT that happens after a

         // do_check failure though.

         if (!_quit || e != Components.results.NS_ERROR_ABORT) {

           if (e.stack) {

             _log("javascript_error",

                  {source_file: "xpcshell/head.js",

                   diagnostic: _exception_message(e) + " - See following stack:",

                   stack: _format_exception_stack(e.stack)});

           } else {

             _log("javascript_error",

                  {source_file: "xpcshell/head.js",

                   diagnostic: _exception_message(e)});

           }

           _do_quit();

         }

       }

       finally {

         do_test_finished(funcName);

       }

     }

   }, Components.interfaces.nsIThread.DISPATCH_NORMAL);

 }

 /**

  * Shows an error message and the current stack and aborts the test.

  *

  * @param error  A message string or an Error object.

  * @param stack  null or nsIStackFrame object or a string containing

  *               \n separated stack lines (as in Error().stack).

  */

 function do_throw(error, stack) {

   let filename = "";

   // If we didn't get passed a stack, maybe the error has one

   // otherwise get it from our call context

   stack = stack || error.stack || Components.stack.caller;

   if (stack instanceof Components.interfaces.nsIStackFrame)

     filename = stack.filename;

   else if (error.fileName)

     filename = error.fileName;

   _log_message_with_stack("test_unexpected_fail",

                           error, stack, filename);

   _passed = false;

   _do_quit();

   throw Components.results.NS_ERROR_ABORT;

 }

 function _format_stack(stack) {

   if (stack instanceof Components.interfaces.nsIStackFrame) {

     let stack_msg = "";

     let frame = stack;

     while (frame != null) {

       stack_msg += frame + "\n";

       frame = frame.caller;

     }

     return stack_msg;

   }

   return "" + stack;

 }

 function do_throw_todo(text, stack) {

   if (!stack)

     stack = Components.stack.caller;

   _passed = false;

   _log_message_with_stack("test_unexpected_pass",

                           text, stack, stack.filename);

   _do_quit();

   throw Components.results.NS_ERROR_ABORT;

 }

 // Make a nice display string from an object that behaves

 // like Error

 function _exception_message(ex) {

   let message = "";

   if (ex.name) {

     message = ex.name + ": ";

   }

   if (ex.message) {

     message += ex.message;

   }

   if (ex.fileName) {

     message += (" at " + ex.fileName);

     if (ex.lineNumber) {

       message += (":" + ex.lineNumber);

     }

   }

   if (message !== "") {

     return message;

   }

   // Force ex to be stringified

   return "" + ex;

 }

 function _log_message_with_stack(action, ex, stack, filename, text) {

   if (stack) {

     _log(action,

          {diagnostic: (text ? text : "") +

                       _exception_message(ex) +

                       " - See following stack:",

           source_file: filename,

           stack: _format_stack(stack)});

   } else {

     _log(action,

          {diagnostic: (text ? text : "") +

                       _exception_message(ex),

           source_file: filename});

   }

 }

 function do_report_unexpected_exception(ex, text) {

   var caller_stack = Components.stack.caller;

   text = text ? text + " - " : "";

   _passed = false;

   _log_message_with_stack("test_unexpected_fail", ex, ex.stack,

                           caller_stack.filename, text + "Unexpected exception ");

   _do_quit();

   throw Components.results.NS_ERROR_ABORT;

 }

 function do_note_exception(ex, text) {

   var caller_stack = Components.stack.caller;

   text = text ? text + " - " : "";

   _log_message_with_stack("test_info", ex, ex.stack,

                           caller_stack.filename, text + "Swallowed exception ");

 }

 function _do_check_neq(left, right, stack, todo) {

   if (!stack)

     stack = Components.stack.caller;

   var text = _wrap_with_quotes_if_necessary(left) + " != " +

              _wrap_with_quotes_if_necessary(right);

   do_report_result(left != right, text, stack, todo);

 }

 function do_check_neq(left, right, stack) {

   if (!stack)

     stack = Components.stack.caller;

   _do_check_neq(left, right, stack, false);

 }

 function todo_check_neq(left, right, stack) {

   if (!stack)

       stack = Components.stack.caller;

   _do_check_neq(left, right, stack, true);

 }

 function do_report_result(passed, text, stack, todo) {

   if (passed) {

     if (todo) {

       do_throw_todo(text, stack);

     } else {

       ++_passedChecks;

       _log("test_pass",

            {source_file: stack.filename,

             test_name: stack.name,

             line_number: stack.lineNumber,

             diagnostic: "[" + stack.name + " : " + stack.lineNumber + "] " +

                         text + "\n"});

     }

   } else {

     if (todo) {

       ++_todoChecks;

       _log("test_known_fail",

            {source_file: stack.filename,

             test_name: stack.name,

             line_number: stack.lineNumber,

             diagnostic: "[" + stack.name + " : " + stack.lineNumber + "] " +

                         text + "\n"});

     } else {

       do_throw(text, stack);

     }

   }

 }

 function _do_check_eq(left, right, stack, todo) {

   if (!stack)

     stack = Components.stack.caller;

   var text = _wrap_with_quotes_if_necessary(left) + " == " +

              _wrap_with_quotes_if_necessary(right);

   do_report_result(left == right, text, stack, todo);

 }

 function do_check_eq(left, right, stack) {

   if (!stack)

     stack = Components.stack.caller;

   _do_check_eq(left, right, stack, false);

 }

 function todo_check_eq(left, right, stack) {

   if (!stack)

       stack = Components.stack.caller;

   _do_check_eq(left, right, stack, true);

 }

 function do_check_true(condition, stack) {

   if (!stack)

     stack = Components.stack.caller;

   do_check_eq(condition, true, stack);

 }

 function todo_check_true(condition, stack) {

   if (!stack)

     stack = Components.stack.caller;

   todo_check_eq(condition, true, stack);

 }

 function do_check_false(condition, stack) {

   if (!stack)

     stack = Components.stack.caller;

   do_check_eq(condition, false, stack);

 }

 function todo_check_false(condition, stack) {

   if (!stack)

     stack = Components.stack.caller;

   todo_check_eq(condition, false, stack);

 }

 function do_check_null(condition, stack=Components.stack.caller) {

   do_check_eq(condition, null, stack);

 }

 function todo_check_null(condition, stack=Components.stack.caller) {

   todo_check_eq(condition, null, stack);

 }

 /**

  * Check that |value| matches |pattern|.

  *

  * A |value| matches a pattern |pattern| if any one of the following is true:

  *

  * - |value| and |pattern| are both objects; |pattern|'s enumerable

  *   properties' values are valid patterns; and for each enumerable

  *   property |p| of |pattern|, plus 'length' if present at all, |value|

  *   has a property |p| whose value matches |pattern.p|. Note that if |j|

  *   has other properties not present in |p|, |j| may still match |p|.

  *

  * - |value| and |pattern| are equal string, numeric, or boolean literals

  *

  * - |pattern| is |undefined| (this is a wildcard pattern)

  *

  * - typeof |pattern| == "function", and |pattern(value)| is true.

  *

  * For example:

  *

  * do_check_matches({x:1}, {x:1})       // pass

  * do_check_matches({x:1}, {})          // fail: all pattern props required

  * do_check_matches({x:1}, {x:2})       // fail: values must match

  * do_check_matches({x:1}, {x:1, y:2})  // pass: extra props tolerated

  *

  * // Property order is irrelevant.

  * do_check_matches({x:"foo", y:"bar"}, {y:"bar", x:"foo"}) // pass

  *

  * do_check_matches({x:undefined}, {x:1}) // pass: 'undefined' is wildcard

  * do_check_matches({x:undefined}, {x:2})

  * do_check_matches({x:undefined}, {y:2}) // fail: 'x' must still be there

  *

  * // Patterns nest.

  * do_check_matches({a:1, b:{c:2,d:undefined}}, {a:1, b:{c:2,d:3}})

  *

  * // 'length' property counts, even if non-enumerable.

  * do_check_matches([3,4,5], [3,4,5])     // pass

  * do_check_matches([3,4,5], [3,5,5])     // fail; value doesn't match

  * do_check_matches([3,4,5], [3,4,5,6])   // fail; length doesn't match

  *

  * // functions in patterns get applied.

  * do_check_matches({foo:function (v) v.length == 2}, {foo:"hi"}) // pass

  * do_check_matches({foo:function (v) v.length == 2}, {bar:"hi"}) // fail

  * do_check_matches({foo:function (v) v.length == 2}, {foo:"hello"}) // fail

  *

  * // We don't check constructors, prototypes, or classes. However, if

  * // pattern has a 'length' property, we require values to match that as

  * // well, even if 'length' is non-enumerable in the pattern. So arrays

  * // are useful as patterns.

  * do_check_matches({0:0, 1:1, length:2}, [0,1])  // pass

  * do_check_matches({0:1}, [1,2])                 // pass

  * do_check_matches([0], {0:0, length:1})         // pass

  *

  * Notes:

  *

  * The 'length' hack gives us reasonably intuitive handling of arrays.

  *

  * This is not a tight pattern-matcher; it's only good for checking data

  * from well-behaved sources. For example:

  * - By default, we don't mind values having extra properties.

  * - We don't check for proxies or getters.

  * - We don't check the prototype chain.

  * However, if you know the values are, say, JSON, which is pretty

  * well-behaved, and if you want to tolerate additional properties

  * appearing on the JSON for backward-compatibility, then do_check_matches

  * is ideal. If you do want to be more careful, you can use function

  * patterns to implement more stringent checks.

  */

 function do_check_matches(pattern, value, stack=Components.stack.caller, todo=false) {

   var matcher = pattern_matcher(pattern);

   var text = "VALUE: " + uneval(value) + "\nPATTERN: " + uneval(pattern) + "\n";

   var diagnosis = []

   if (matcher(value, diagnosis)) {

     do_report_result(true, "value matches pattern:\n" + text, stack, todo);

   } else {

     text = ("value doesn't match pattern:\n" +

             text +

             "DIAGNOSIS: " +

             format_pattern_match_failure(diagnosis[0]) + "\n");

     do_report_result(false, text, stack, todo);

   }

 }

 function todo_check_matches(pattern, value, stack=Components.stack.caller) {

   do_check_matches(pattern, value, stack, true);

 }

 // Return a pattern-matching function of one argument, |value|, that

 // returns true if |value| matches |pattern|.

 //

 // If the pattern doesn't match, and the pattern-matching function was

 // passed its optional |diagnosis| argument, the pattern-matching function

 // sets |diagnosis|'s '0' property to a JSON-ish description of the portion

 // of the pattern that didn't match, which can be formatted legibly by

 // format_pattern_match_failure.

 function pattern_matcher(pattern) {

   function explain(diagnosis, reason) {

     if (diagnosis) {

       diagnosis[0] = reason;

     }

     return false;

   }

   if (typeof pattern == "function") {

     return pattern;

   } else if (typeof pattern == "object" && pattern) {

     var matchers = [[p, pattern_matcher(pattern[p])] for (p in pattern)];

     // Kludge: include 'length', if not enumerable. (If it is enumerable,

     // we picked it up in the array comprehension, above.

     ld = Object.getOwnPropertyDescriptor(pattern, 'length');

     if (ld && !ld.enumerable) {

       matchers.push(['length', pattern_matcher(pattern.length)])

     }

     return function (value, diagnosis) {

       if (!(value && typeof value == "object")) {

         return explain(diagnosis, "value not object");

       }

       for (let [p, m] of matchers) {

         var element_diagnosis = [];

         if (!(p in value && m(value[p], element_diagnosis))) {

           return explain(diagnosis, { property:p,

                                       diagnosis:element_diagnosis[0] });

         }

       }

       return true;

     };

   } else if (pattern === undefined) {

     return function(value) { return true; };

   } else {

     return function (value, diagnosis) {

       if (value !== pattern) {

         return explain(diagnosis, "pattern " + uneval(pattern) + " not === to value " + uneval(value));

       }

       return true;

     };

   }

 }

 // Format an explanation for a pattern match failure, as stored in the

 // second argument to a matching function.

 function format_pattern_match_failure(diagnosis, indent="") {

   var a;

   if (!diagnosis) {

     a = "Matcher did not explain reason for mismatch.";

   } else if (typeof diagnosis == "string") {

     a = diagnosis;

   } else if (diagnosis.property) {

     a = "Property " + uneval(diagnosis.property) + " of object didn't match:\n";

     a += format_pattern_match_failure(diagnosis.diagnosis, indent + "  ");

   }

   return indent + a;

 }

 // Check that |func| throws an nsIException that has

 // |Components.results[resultName]| as the value of its 'result' property.

 function do_check_throws_nsIException(func, resultName,

                                       stack=Components.stack.caller, todo=false)

 {

   let expected = Components.results[resultName];

   if (typeof expected !== 'number') {

     do_throw("do_check_throws_nsIException requires a Components.results" +

              " property name, not " + uneval(resultName), stack);

   }

   let msg = ("do_check_throws_nsIException: func should throw" +

              " an nsIException whose 'result' is Components.results." +

              resultName);

   try {

     func();

   } catch (ex) {

     if (!(ex instanceof Components.interfaces.nsIException) ||

         ex.result !== expected) {

       do_report_result(false, msg + ", threw " + legible_exception(ex) +

                        " instead", stack, todo);

     }

     do_report_result(true, msg, stack, todo);

     return;

   }

   // Call this here, not in the 'try' clause, so do_report_result's own

   // throw doesn't get caught by our 'catch' clause.

   do_report_result(false, msg + ", but returned normally", stack, todo);

 }

 // Produce a human-readable form of |exception|. This looks up

 // Components.results values, tries toString methods, and so on.

 function legible_exception(exception)

 {

   switch (typeof exception) {

     case 'object':

     if (exception instanceof Components.interfaces.nsIException) {

       return "nsIException instance: " + uneval(exception.toString());

     }

     return exception.toString();

     case 'number':

     for (let name in Components.results) {

       if (exception === Components.results[name]) {

         return "Components.results." + name;

       }

     }

     // Fall through.

     default:

     return uneval(exception);

   }

 }

 function do_check_instanceof(value, constructor,

                              stack=Components.stack.caller, todo=false) {

   do_report_result(value instanceof constructor,

                    "value should be an instance of " + constructor.name,

                    stack, todo);

 }

 function todo_check_instanceof(value, constructor,

                              stack=Components.stack.caller) {

   do_check_instanceof(value, constructor, stack, true);

 }

 function do_test_pending(aName) {

   ++_tests_pending;

   _log("test_pending",

        {_message: "TEST-INFO | (xpcshell/head.js) | test" +

                   (aName ? " " + aName : "") +

                   " pending (" + _tests_pending + ")\n"});

 }

 function do_test_finished(aName) {

   _log("test_finish",

        {_message: "TEST-INFO | (xpcshell/head.js) | test" +

                   (aName ? " " + aName : "") +

                   " finished (" + _tests_pending + ")\n"});

   if (--_tests_pending == 0)

     _do_quit();

 }

 function do_get_file(path, allowNonexistent) {

   try {

     let lf = Components.classes["@mozilla.org/file/directory_service;1"]

       .getService(Components.interfaces.nsIProperties)

       .get("CurWorkD", Components.interfaces.nsILocalFile);

     let bits = path.split("/");

     for (let i = 0; i < bits.length; i++) {

       if (bits[i]) {

         if (bits[i] == "..")

           lf = lf.parent;

         else

           lf.append(bits[i]);

       }

     }

     if (!allowNonexistent && !lf.exists()) {

       // Not using do_throw(): caller will continue.

       _passed = false;

       var stack = Components.stack.caller;

       _log("test_unexpected_fail",

            {source_file: stack.filename,

             test_name: stack.name,

             line_number: stack.lineNumber,

             diagnostic: "[" + stack.name + " : " + stack.lineNumber + "] " +

                         lf.path + " does not exist\n"});

     }

     return lf;

   }

   catch (ex) {

     do_throw(ex.toString(), Components.stack.caller);

   }

   return null;

 }

 // do_get_cwd() isn't exactly self-explanatory, so provide a helper

 function do_get_cwd() {

   return do_get_file("");

 }

 function do_load_manifest(path) {

   var lf = do_get_file(path);

   const nsIComponentRegistrar = Components.interfaces.nsIComponentRegistrar;

   do_check_true(Components.manager instanceof nsIComponentRegistrar);

   // Previous do_check_true() is not a test check.

   ++_falsePassedChecks;

   Components.manager.autoRegister(lf);

 }

 /**

  * Parse a DOM document.

  *

  * @param aPath File path to the document.

  * @param aType Content type to use in DOMParser.

  *

  * @return nsIDOMDocument from the file.

  */

 function do_parse_document(aPath, aType) {

   switch (aType) {

     case "application/xhtml+xml":

     case "application/xml":

     case "text/xml":

       break;

     default:

       do_throw("type: expected application/xhtml+xml, application/xml or text/xml," +

                  " got '" + aType + "'",

                Components.stack.caller);

   }

   var lf = do_get_file(aPath);

   const C_i = Components.interfaces;

   const parserClass = "@mozilla.org/xmlextras/domparser;1";

   const streamClass = "@mozilla.org/network/file-input-stream;1";

   var stream = Components.classes[streamClass]

                          .createInstance(C_i.nsIFileInputStream);

   stream.init(lf, -1, -1, C_i.nsIFileInputStream.CLOSE_ON_EOF);

   var parser = Components.classes[parserClass]

                          .createInstance(C_i.nsIDOMParser);

   var doc = parser.parseFromStream(stream, null, lf.fileSize, aType);

   parser = null;

   stream = null;

   lf = null;

   return doc;

 }

 /**

  * Registers a function that will run when the test harness is done running all

  * tests.

  *

  * @param aFunction

  *        The function to be called when the test harness has finished running.

  */

 function do_register_cleanup(aFunction)

 {

   _cleanupFunctions.push(aFunction);

 }

 /**

  * Returns the directory for a temp dir, which is created by the

  * test harness. Every test gets its own temp dir.

  *

  * @return nsILocalFile of the temporary directory

  */

 function do_get_tempdir() {

   let env = Components.classes["@mozilla.org/process/environment;1"]

                       .getService(Components.interfaces.nsIEnvironment);

   // the python harness sets this in the environment for us

   let path = env.get("XPCSHELL_TEST_TEMP_DIR");

   let file = Components.classes["@mozilla.org/file/local;1"]

                        .createInstance(Components.interfaces.nsILocalFile);

   file.initWithPath(path);

   return file;

 }

 /**

  * Returns the directory for crashreporter minidumps.

  *

  * @return nsILocalFile of the minidump directory

  */

 function do_get_minidumpdir() {

   let env = Components.classes["@mozilla.org/process/environment;1"]

                       .getService(Components.interfaces.nsIEnvironment);

   // the python harness may set this in the environment for us

   let path = env.get("XPCSHELL_MINIDUMP_DIR");

   if (path) {

     let file = Components.classes["@mozilla.org/file/local;1"]

                          .createInstance(Components.interfaces.nsILocalFile);

     file.initWithPath(path);

     return file;

   } else {

     return do_get_tempdir();

   }

 }

 /**

  * Registers a directory with the profile service,

  * and return the directory as an nsILocalFile.

  *

  * @return nsILocalFile of the profile directory.

  */

 function do_get_profile() {

   if (!runningInParent) {

     _log("test_info",

          {_message: "TEST-INFO | (xpcshell/head.js) | Ignoring profile creation from child process.\n"});

     return null;

   }

   if (!_profileInitialized) {

     // Since we have a profile, we will notify profile shutdown topics at

     // the end of the current test, to ensure correct cleanup on shutdown.

     do_register_cleanup(function() {

       let obsSvc = Components.classes["@mozilla.org/observer-service;1"].

                    getService(Components.interfaces.nsIObserverService);

       obsSvc.notifyObservers(null, "profile-change-net-teardown", null);

       obsSvc.notifyObservers(null, "profile-change-teardown", null);

       obsSvc.notifyObservers(null, "profile-before-change", null);

     });

   }

   let env = Components.classes["@mozilla.org/process/environment;1"]

                       .getService(Components.interfaces.nsIEnvironment);

   // the python harness sets this in the environment for us

   let profd = env.get("XPCSHELL_TEST_PROFILE_DIR");

   let file = Components.classes["@mozilla.org/file/local;1"]

                        .createInstance(Components.interfaces.nsILocalFile);

   file.initWithPath(profd);

   let dirSvc = Components.classes["@mozilla.org/file/directory_service;1"]

                          .getService(Components.interfaces.nsIProperties);

   let provider = {

     getFile: function(prop, persistent) {

       persistent.value = true;

       if (prop == "ProfD" || prop == "ProfLD" || prop == "ProfDS" ||

           prop == "ProfLDS" || prop == "TmpD") {

         return file.clone();

       }

       throw Components.results.NS_ERROR_FAILURE;

     },

     QueryInterface: function(iid) {

       if (iid.equals(Components.interfaces.nsIDirectoryServiceProvider) ||

           iid.equals(Components.interfaces.nsISupports)) {

         return this;

       }

       throw Components.results.NS_ERROR_NO_INTERFACE;

     }

   };

   dirSvc.QueryInterface(Components.interfaces.nsIDirectoryService)

         .registerProvider(provider);

   let obsSvc = Components.classes["@mozilla.org/observer-service;1"].

         getService(Components.interfaces.nsIObserverService);

   // We need to update the crash events directory when the profile changes.

   if (runningInParent &&

       "@mozilla.org/toolkit/crash-reporter;1" in Components.classes) {

     let crashReporter =

         Components.classes["@mozilla.org/toolkit/crash-reporter;1"]

                           .getService(Components.interfaces.nsICrashReporter);

     crashReporter.UpdateCrashEventsDir();

   }

   if (!_profileInitialized) {

     obsSvc.notifyObservers(null, "profile-do-change", "xpcshell-do-get-profile");

     _profileInitialized = true;

   }

   // The methods of 'provider' will retain this scope so null out everything

   // to avoid spurious leak reports.

   env = null;

   profd = null;

   dirSvc = null;

   provider = null;

   obsSvc = null;

   return file.clone();

 }

 /**

  * This function loads head.js (this file) in the child process, so that all

  * functions defined in this file (do_throw, etc) are available to subsequent

  * sendCommand calls.  It also sets various constants used by these functions.

  *

  * (Note that you may use sendCommand without calling this function first;  you

  * simply won't have any of the functions in this file available.)

  */

 function do_load_child_test_harness()

 {

   // Make sure this isn't called from child process

   if (!runningInParent) {

     do_throw("run_test_in_child cannot be called from child!");

   }

   // Allow to be called multiple times, but only run once

   if (typeof do_load_child_test_harness.alreadyRun != "undefined")

     return;

   do_load_child_test_harness.alreadyRun = 1;

   _XPCSHELL_PROCESS = "parent";

   let command =

         "const _HEAD_JS_PATH=" + uneval(_HEAD_JS_PATH) + "; "

       + "const _HTTPD_JS_PATH=" + uneval(_HTTPD_JS_PATH) + "; "

       + "const _HEAD_FILES=" + uneval(_HEAD_FILES) + "; "

       + "const _TAIL_FILES=" + uneval(_TAIL_FILES) + "; "

       + "const _XPCSHELL_PROCESS='child';";

   if (this._TESTING_MODULES_DIR) {

     command += " const _TESTING_MODULES_DIR=" + uneval(_TESTING_MODULES_DIR) + ";";

   }

   command += " load(_HEAD_JS_PATH);";

   sendCommand(command);

 }

 /**

  * Runs an entire xpcshell unit test in a child process (rather than in chrome,

  * which is the default).

  *

  * This function returns immediately, before the test has completed.  

  *

  * @param testFile

  *        The name of the script to run.  Path format same as load().

  * @param optionalCallback.

  *        Optional function to be called (in parent) when test on child is

  *        complete.  If provided, the function must call do_test_finished();

  */

 function run_test_in_child(testFile, optionalCallback) 

 {

   var callback = (typeof optionalCallback == 'undefined') ? 

                     do_test_finished : optionalCallback;

   do_load_child_test_harness();

   var testPath = do_get_file(testFile).path.replace(/\\/g, "/");

   do_test_pending("run in child");

   sendCommand("_log('child_test_start', {_message: 'CHILD-TEST-STARTED'}); "

               + "const _TEST_FILE=['" + testPath + "']; _execute_test(); "

               + "_log('child_test_end', {_message: 'CHILD-TEST-COMPLETED'});",

               callback);

 }

 /**

  * Execute a given function as soon as a particular cross-process message is received.

  * Must be paired with do_send_remote_message or equivalent ProcessMessageManager calls.

  */

 function do_await_remote_message(name, callback)

 {

   var listener = {

     receiveMessage: function(message) {

       if (message.name == name) {

         mm.removeMessageListener(name, listener);

         callback();

         do_test_finished();

       }

     }

   };

   var mm;

   if (runningInParent) {

     mm = Cc["@mozilla.org/parentprocessmessagemanager;1"].getService(Ci.nsIMessageBroadcaster);

   } else {

     mm = Cc["@mozilla.org/childprocessmessagemanager;1"].getService(Ci.nsISyncMessageSender);

   }

   do_test_pending();

   mm.addMessageListener(name, listener);

 }

 /**

  * Asynchronously send a message to all remote processes. Pairs with do_await_remote_message

  * or equivalent ProcessMessageManager listeners.

  */

 function do_send_remote_message(name) {

   var mm;

   var sender;

   if (runningInParent) {

     mm = Cc["@mozilla.org/parentprocessmessagemanager;1"].getService(Ci.nsIMessageBroadcaster);

     sender = 'broadcastAsyncMessage';

   } else {

     mm = Cc["@mozilla.org/childprocessmessagemanager;1"].getService(Ci.nsISyncMessageSender);

     sender = 'sendAsyncMessage';

   }

   mm[sender](name);

 }

 /**

  * Add a test function to the list of tests that are to be run asynchronously.

  *

  * Each test function must call run_next_test() when it's done. Test files

  * should call run_next_test() in their run_test function to execute all

  * async tests.

  *

  * @return the test function that was passed in.

  */

 let _gTests = [];

 function add_test(func) {

   _gTests.push([false, func]);

   return func;

 }

 // We lazy import Task.jsm so we don't incur a run-time penalty for all tests.

 let _Task;

 /**

  * Add a test function which is a Task function.

  *

  * Task functions are functions fed into Task.jsm's Task.spawn(). They are

  * generators that emit promises.

  *

  * If an exception is thrown, a do_check_* comparison fails, or if a rejected

  * promise is yielded, the test function aborts immediately and the test is

  * reported as a failure.

  *

  * Unlike add_test(), there is no need to call run_next_test(). The next test

  * will run automatically as soon the task function is exhausted. To trigger

  * premature (but successful) termination of the function, simply return or

  * throw a Task.Result instance.

  *

  * Example usage:

  *

  * add_task(function test() {

  *   let result = yield Promise.resolve(true);

  *

  *   do_check_true(result);

  *

  *   let secondary = yield someFunctionThatReturnsAPromise(result);

  *   do_check_eq(secondary, "expected value");

  * });

  *

  * add_task(function test_early_return() {

  *   let result = yield somethingThatReturnsAPromise();

  *

  *   if (!result) {

  *     // Test is ended immediately, with success.

  *     return;

  *   }

  *

  *   do_check_eq(result, "foo");

  * });

  */

 function add_task(func) {

   if (!_Task) {

     let ns = {};

     _Task = Components.utils.import("resource://gre/modules/Task.jsm", ns).Task;

   }

   _gTests.push([true, func]);

 }

 /**

  * Runs the next test function from the list of async tests.

  */

 let _gRunningTest = null;

 let _gTestIndex = 0; // The index of the currently running test.

 let _gTaskRunning = false;

 function run_next_test()

 {

   if (_gTaskRunning) {

     throw new Error("run_next_test() called from an add_task() test function. " +

                     "run_next_test() should not be called from inside add_task() " +

                     "under any circumstances!");

   }

   function _run_next_test()

   {

     if (_gTestIndex < _gTests.length) {

       // Flush uncaught errors as early and often as possible.

       _Promise.Debugging.flushUncaughtErrors();

       let _isTask;

       [_isTask, _gRunningTest] = _gTests[_gTestIndex++];

       print("TEST-INFO | " + _TEST_FILE + " | Starting " + _gRunningTest.name);

       do_test_pending(_gRunningTest.name);

       if (_isTask) {

         _gTaskRunning = true;

         _Task.spawn(_gRunningTest).then(

           () => { _gTaskRunning = false; run_next_test(); },

           (ex) => { _gTaskRunning = false; do_report_unexpected_exception(ex); }

         );

       } else {

         // Exceptions do not kill asynchronous tests, so they'll time out.

         try {

           _gRunningTest();

         } catch (e) {

           do_throw(e);

         }

       }

     }

   }

   // For sane stacks during failures, we execute this code soon, but not now.

   // We do this now, before we call do_test_finished(), to ensure the pending

   // counter (_tests_pending) never reaches 0 while we still have tests to run

   // (do_execute_soon bumps that counter).

   do_execute_soon(_run_next_test, "run_next_test " + _gTestIndex);

   if (_gRunningTest !== null) {

     // Close the previous test do_test_pending call.

     do_test_finished(_gRunningTest.name);

   }

 }

 try {

   if (runningInParent) {

     // Always use network provider for geolocation tests

     // so we bypass the OSX dialog raised by the corelocation provider

     let prefs = Components.classes["@mozilla.org/preferences-service;1"]

       .getService(Components.interfaces.nsIPrefBranch);

     prefs.setBoolPref("geo.provider.testing", true);

   }

 } catch (e) { }