diff -r 000000000000 -r 6474c204b198 toolkit/modules/tests/xpcshell/test_task.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/modules/tests/xpcshell/test_task.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,387 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * This file tests the Task.jsm module.
+ */
+
+////////////////////////////////////////////////////////////////////////////////
+/// Globals
+
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+const Cu = Components.utils;
+const Cr = Components.results;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "Promise",
+                                  "resource://gre/modules/Promise.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Services",
+                                  "resource://gre/modules/Services.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Task",
+                                  "resource://gre/modules/Task.jsm");
+
+/**
+ * Returns a promise that will be resolved with the given value, when an event
+ * posted on the event loop of the main thread is processed.
+ */
+function promiseResolvedLater(aValue) {
+  let deferred = Promise.defer();
+  Services.tm.mainThread.dispatch(function () deferred.resolve(aValue),
+                                  Ci.nsIThread.DISPATCH_NORMAL);
+  return deferred.promise;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// Tests
+
+function run_test()
+{
+  run_next_test();
+}
+
+add_test(function test_normal()
+{
+  Task.spawn(function () {
+    let result = yield Promise.resolve("Value");
+    for (let i = 0; i < 3; i++) {
+      result += yield promiseResolvedLater("!");
+    }
+    throw new Task.Result("Task result: " + result);
+  }).then(function (result) {
+    do_check_eq("Task result: Value!!!", result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_exceptions()
+{
+  Task.spawn(function () {
+    try {
+      yield Promise.reject("Rejection result by promise.");
+      do_throw("Exception expected because the promise was rejected.");
+    } catch (ex) {
+      // We catch this exception now, we will throw a different one later.
+      do_check_eq("Rejection result by promise.", ex);
+    }
+    throw new Error("Exception uncaught by task.");
+  }).then(function (result) {
+    do_throw("Unexpected success!");
+  }, function (ex) {
+    do_check_eq("Exception uncaught by task.", ex.message);
+    run_next_test();
+  });
+});
+
+add_test(function test_recursion()
+{
+  function task_fibonacci(n) {
+    throw new Task.Result(n < 2 ? n : (yield task_fibonacci(n - 1)) +
+                                      (yield task_fibonacci(n - 2)));
+  };
+
+  Task.spawn(task_fibonacci(6)).then(function (result) {
+    do_check_eq(8, result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_spawn_primitive()
+{
+  function fibonacci(n) {
+    return n < 2 ? n : fibonacci(n - 1) + fibonacci(n - 2);
+  };
+
+  // Polymorphism between task and non-task functions (see "test_recursion").
+  Task.spawn(fibonacci(6)).then(function (result) {
+    do_check_eq(8, result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_spawn_function()
+{
+  Task.spawn(function () {
+    return "This is not a generator.";
+  }).then(function (result) {
+    do_check_eq("This is not a generator.", result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_spawn_function_this()
+{
+  Task.spawn(function () {
+    return this;
+  }).then(function (result) {
+    // Since the task function wasn't defined in strict mode, its "this" object
+    // should be the same as the "this" object in this function, i.e. the global
+    // object.
+    do_check_eq(result, this);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_spawn_function_this_strict()
+{
+  "use strict";
+  Task.spawn(function () {
+    return this;
+  }).then(function (result) {
+    // Since the task function was defined in strict mode, its "this" object
+    // should be undefined.
+    do_check_eq(typeof(result), "undefined");
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_spawn_function_returning_promise()
+{
+  Task.spawn(function () {
+    return promiseResolvedLater("Resolution value.");
+  }).then(function (result) {
+    do_check_eq("Resolution value.", result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_spawn_function_exceptions()
+{
+  Task.spawn(function () {
+    throw new Error("Exception uncaught by task.");
+  }).then(function (result) {
+    do_throw("Unexpected success!");
+  }, function (ex) {
+    do_check_eq("Exception uncaught by task.", ex.message);
+    run_next_test();
+  });
+});
+
+add_test(function test_spawn_function_taskresult()
+{
+  Task.spawn(function () {
+    throw new Task.Result("Task result");
+  }).then(function (result) {
+    do_check_eq("Task result", result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_yielded_undefined()
+{
+  Task.spawn(function () {
+    yield;
+    throw new Task.Result("We continued correctly.");
+  }).then(function (result) {
+    do_check_eq("We continued correctly.", result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_yielded_primitive()
+{
+  Task.spawn(function () {
+    throw new Task.Result("Primitive " + (yield "value."));
+  }).then(function (result) {
+    do_check_eq("Primitive value.", result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_star_normal()
+{
+  Task.spawn(function* () {
+    let result = yield Promise.resolve("Value");
+    for (let i = 0; i < 3; i++) {
+      result += yield promiseResolvedLater("!");
+    }
+    return "Task result: " + result;
+  }).then(function (result) {
+    do_check_eq("Task result: Value!!!", result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_star_exceptions()
+{
+  Task.spawn(function* () {
+    try {
+      yield Promise.reject("Rejection result by promise.");
+      do_throw("Exception expected because the promise was rejected.");
+    } catch (ex) {
+      // We catch this exception now, we will throw a different one later.
+      do_check_eq("Rejection result by promise.", ex);
+    }
+    throw new Error("Exception uncaught by task.");
+  }).then(function (result) {
+    do_throw("Unexpected success!");
+  }, function (ex) {
+    do_check_eq("Exception uncaught by task.", ex.message);
+    run_next_test();
+  });
+});
+
+add_test(function test_star_recursion()
+{
+  function* task_fibonacci(n) {
+    return n < 2 ? n : (yield task_fibonacci(n - 1)) +
+                       (yield task_fibonacci(n - 2));
+  };
+
+  Task.spawn(task_fibonacci(6)).then(function (result) {
+    do_check_eq(8, result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_mixed_legacy_and_star()
+{
+  Task.spawn(function* () {
+    return yield (function() {
+      throw new Task.Result(yield 5);
+    })();
+  }).then(function (result) {
+    do_check_eq(5, result);
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_async_function_from_generator()
+{
+  Task.spawn(function* () {
+    let object = {
+      asyncFunction: Task.async(function* (param) {
+        do_check_eq(this, object);
+        return param;
+      })
+    };
+
+    // Ensure the async function returns a promise that resolves as expected.
+    do_check_eq((yield object.asyncFunction(1)), 1);
+
+    // Ensure a second call to the async function also returns such a promise.
+    do_check_eq((yield object.asyncFunction(3)), 3);
+  }).then(function () {
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_async_function_from_function()
+{
+  Task.spawn(function* () {
+    return Task.spawn(function* () {
+      let object = {
+        asyncFunction: Task.async(function (param) {
+          do_check_eq(this, object);
+          return param;
+        })
+      };
+
+      // Ensure the async function returns a promise that resolves as expected.
+      do_check_eq((yield object.asyncFunction(5)), 5);
+
+      // Ensure a second call to the async function also returns such a promise.
+      do_check_eq((yield object.asyncFunction(7)), 7);
+    });
+  }).then(function () {
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_async_function_that_throws_rejects_promise()
+{
+  Task.spawn(function* () {
+    let object = {
+      asyncFunction: Task.async(function* () {
+        throw "Rejected!";
+      })
+    };
+
+    yield object.asyncFunction();
+  }).then(function () {
+    do_throw("unexpected success calling async function that throws error");
+  }, function (ex) {
+    do_check_eq(ex, "Rejected!");
+    run_next_test();
+  });
+});
+
+add_test(function test_async_return_function()
+{
+  Task.spawn(function* () {
+    // Ensure an async function that returns a function resolves to the function
+    // itself instead of calling the function and resolving to its return value.
+    return Task.spawn(function* () {
+      let returnValue = function () {
+        return "These aren't the droids you're looking for.";
+      };
+
+      let asyncFunction = Task.async(function () {
+        return returnValue;
+      });
+
+      do_check_eq((yield asyncFunction()), returnValue);
+    });
+  }).then(function () {
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_async_throw_argument_not_function()
+{
+  Task.spawn(function* () {
+    // Ensure Task.async throws if its aTask argument is not a function.
+    Assert.throws(() => Task.async("not a function"),
+                  /aTask argument must be a function/);
+  }).then(function () {
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});
+
+add_test(function test_async_throw_on_function_in_place_of_promise()
+{
+  Task.spawn(function* () {
+    // Ensure Task.spawn throws if passed an async function.
+    Assert.throws(() => Task.spawn(Task.async(function* () {})),
+                  /Cannot use an async function in place of a promise/);
+  }).then(function () {
+    run_next_test();
+  }, function (ex) {
+    do_throw("Unexpected error: " + ex);
+  });
+});