1 files changed, 42 insertions, 0 deletions
diff --git a/testing/xpcshell/example/unit/test_prefs_defaults_and_file.js b/testing/xpcshell/example/unit/test_prefs_defaults_and_file.js
new file mode 100644
index 0000000000..8a56d49c34
--- /dev/null
+++ b/testing/xpcshell/example/unit/test_prefs_defaults_and_file.js
@@ -0,0 +1,42 @@
+/* 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/. */
+
+// Bug 1781025 - ESLint's use of multi-ini doesn't fully cope with
+// mozilla-central's use of .ini files
+// eslint-disable-next-line no-unused-vars
+function run_test() {
+  /* import-globals-from prefs_test_common.js */
+  load("prefs_test_common.js");
+
+  check_common_xpcshell_with_prefs();
+
+  Assert.ok(
+    has_pref_from_manifest_file_section(),
+    "Should have pref set for file in xpcshell-with-prefs.ini"
+  );
+
+  Assert.equal(
+    Services.prefs.getIntPref("dummy.pref.from.test.file"),
+    2,
+    "Value of pref that was set once at the file in xpcshell-with-prefs.ini"
+  );
+
+  Assert.equal(
+    Services.prefs.getStringPref("dummy.pref.from.test.duplicate"),
+    "final",
+    "The last pref takes precedence when duplicated"
+  );
+
+  Assert.equal(
+    Services.prefs.getIntPref("dummy.pref.from.test.manifest"),
+    1337,
+    "File-specific pref takes precedence over manifest defaults"
+  );
+
+  Assert.equal(
+    Services.prefs.getStringPref("dummy.pref.from.test.ancestor"),
+    "Ancestor",
+    "Pref in manifest defaults without file-specific override should be set"
+  );
+}