1 files changed, 46 insertions, 0 deletions
diff --git a/devtools/client/debugger/src/utils/task.js b/devtools/client/debugger/src/utils/task.js
new file mode 100644
index 0000000000..012baaba37
--- /dev/null
+++ b/devtools/client/debugger/src/utils/task.js
@@ -0,0 +1,46 @@
+/* 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/>. */
+
+// @flow
+
+/**
+ * This object provides the public module functions.
+ */
+export const Task = {
+  // XXX: Not sure if this works in all cases...
+  async: function(task: any) {
+    return function() {
+      return Task.spawn(task, this, arguments);
+    };
+  },
+
+  /**
+   * Creates and starts a new task.
+   * @param task A generator function
+   * @return A promise, resolved when the task terminates
+   */
+  spawn: function(task: any, scope: any, args: any): Promise<any> {
+    return new Promise(function(resolve, reject) {
+      const iterator = task.apply(scope, args);
+
+      const callNext = lastValue => {
+        const iteration = iterator.next(lastValue);
+        Promise.resolve(iteration.value)
+          .then(value => {
+            if (iteration.done) {
+              resolve(value);
+            } else {
+              callNext(value);
+            }
+          })
+          .catch(error => {
+            reject(error);
+            iterator.throw(error);
+          });
+      };
+
+      callNext(undefined);
+    });
+  },
+};