1 files changed, 65 insertions, 0 deletions
diff --git a/testing/modules/tests/xpcshell/test_mockRegistrar.js b/testing/modules/tests/xpcshell/test_mockRegistrar.js
new file mode 100644
index 0000000000..de4224a092
--- /dev/null
+++ b/testing/modules/tests/xpcshell/test_mockRegistrar.js
@@ -0,0 +1,65 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const { MockRegistrar } = ChromeUtils.importESModule(
+  "resource://testing-common/MockRegistrar.sys.mjs"
+);
+
+function platformInfo(injectedValue) {
+  this.platformVersion = injectedValue;
+}
+
+platformInfo.prototype = {
+  platformVersion: "some version",
+  platformBuildID: "some id",
+  QueryInterface: ChromeUtils.generateQI(["nsIPlatformInfo"]),
+};
+
+add_test(function test_register() {
+  let localPlatformInfo = {
+    platformVersion: "local version",
+    platformBuildID: "local id",
+    QueryInterface: ChromeUtils.generateQI(["nsIPlatformInfo"]),
+  };
+
+  MockRegistrar.register("@mozilla.org/xre/app-info;1", localPlatformInfo);
+  Assert.equal(
+    Cc["@mozilla.org/xre/app-info;1"].createInstance(Ci.nsIPlatformInfo)
+      .platformVersion,
+    "local version"
+  );
+  run_next_test();
+});
+
+add_test(function test_register_with_arguments() {
+  MockRegistrar.register("@mozilla.org/xre/app-info;1", platformInfo, [
+    "override",
+  ]);
+  Assert.equal(
+    Cc["@mozilla.org/xre/app-info;1"].createInstance(Ci.nsIPlatformInfo)
+      .platformVersion,
+    "override"
+  );
+  run_next_test();
+});
+
+add_test(function test_register_twice() {
+  MockRegistrar.register("@mozilla.org/xre/app-info;1", platformInfo, [
+    "override",
+  ]);
+  Assert.equal(
+    Cc["@mozilla.org/xre/app-info;1"].createInstance(Ci.nsIPlatformInfo)
+      .platformVersion,
+    "override"
+  );
+
+  MockRegistrar.register("@mozilla.org/xre/app-info;1", platformInfo, [
+    "override again",
+  ]);
+  Assert.equal(
+    Cc["@mozilla.org/xre/app-info;1"].createInstance(Ci.nsIPlatformInfo)
+      .platformVersion,
+    "override again"
+  );
+  run_next_test();
+});