1 files changed, 32 insertions, 0 deletions
diff --git a/devtools/shared/tests/unit/test_defer.js b/devtools/shared/tests/unit/test_defer.js
new file mode 100644
index 000000000..c0babe961
--- /dev/null
+++ b/devtools/shared/tests/unit/test_defer.js
@@ -0,0 +1,32 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const defer = require("devtools/shared/defer");
+
+function testResolve() {
+  const deferred = defer();
+  deferred.resolve("success");
+  return deferred.promise;
+}
+
+function testReject() {
+  const deferred = defer();
+  deferred.reject("error");
+  return deferred.promise;
+}
+
+add_task(function* () {
+  const success = yield testResolve();
+  equal(success, "success");
+
+  let error;
+  try {
+    yield testReject();
+  } catch (e) {
+    error = e;
+  }
+
+  equal(error, "error");
+});