1 files changed, 41 insertions, 0 deletions
diff --git a/toolkit/components/glean/tests/xpcshell/test_FOGInit.js b/toolkit/components/glean/tests/xpcshell/test_FOGInit.js
new file mode 100644
index 0000000000..f8c4a410ad
--- /dev/null
+++ b/toolkit/components/glean/tests/xpcshell/test_FOGInit.js
@@ -0,0 +1,41 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+
+add_setup(
+  /* on Android FOG is set up through head.js */
+  { skip_if: () => AppConstants.platform == "android" },
+  function test_setup() {
+    // FOG needs a profile directory to put its data in.
+    do_get_profile();
+
+    // Glean init (via `chrono`) gets the timezone via unprotected write.
+    // This is being worked around:
+    // https://github.com/chronotope/chrono/pull/677
+    // Until that reaches a release and we update to it (bug 1780401), ensure
+    // local time has been loaded by JS before we kick of Glean init.
+    new Date().getHours(); // used for its side effect.
+
+    // We need to initialize it once, otherwise operations will be stuck in the pre-init queue.
+    Services.fog.initializeFOG();
+  }
+);
+
+add_task(function test_fog_init_works() {
+  if (new Date().getHours() >= 3 && new Date().getHours() <= 4) {
+    // We skip this test if it's too close to 4AM, when we might send a
+    // "metrics" ping between init and this test being run.
+    Assert.ok(true, "Too close to 'metrics' ping send window. Skipping test.");
+    return;
+  }
+  Assert.greater(
+    Glean.fog.initialization.testGetValue(),
+    0,
+    "FOG init happened, and its time was measured."
+  );
+});