1 files changed, 42 insertions, 0 deletions
diff --git a/modules/libpref/test/unit/test_locked_file_prefs.js b/modules/libpref/test/unit/test_locked_file_prefs.js
new file mode 100644
index 0000000000..4e15f9e3e2
--- /dev/null
+++ b/modules/libpref/test/unit/test_locked_file_prefs.js
@@ -0,0 +1,42 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/  */
+
+// This file tests the `locked` attribute in default pref files.
+
+const ps = Services.prefs;
+
+add_test(function notChangedFromAPI() {
+  ps.resetPrefs();
+  ps.readDefaultPrefsFromFile(do_get_file("data/testPrefLocked.js"));
+  Assert.strictEqual(ps.getIntPref("testPref.unlocked.int"), 333);
+  Assert.strictEqual(ps.getIntPref("testPref.locked.int"), 444);
+
+  // Unlocked pref: can set the user value, which is used upon reading.
+  ps.setIntPref("testPref.unlocked.int", 334);
+  Assert.ok(ps.prefHasUserValue("testPref.unlocked.int"), "has a user value");
+  Assert.strictEqual(ps.getIntPref("testPref.unlocked.int"), 334);
+
+  // Locked pref: can set the user value, but the default value is used upon
+  // reading.
+  ps.setIntPref("testPref.locked.int", 445);
+  Assert.ok(ps.prefHasUserValue("testPref.locked.int"), "has a user value");
+  Assert.strictEqual(ps.getIntPref("testPref.locked.int"), 444);
+
+  // After unlocking, the user value is used.
+  ps.unlockPref("testPref.locked.int");
+  Assert.ok(ps.prefHasUserValue("testPref.locked.int"), "has a user value");
+  Assert.strictEqual(ps.getIntPref("testPref.locked.int"), 445);
+
+  run_next_test();
+});
+
+add_test(function notChangedFromUserPrefs() {
+  ps.resetPrefs();
+  ps.readDefaultPrefsFromFile(do_get_file("data/testPrefLocked.js"));
+  ps.readUserPrefsFromFile(do_get_file("data/testPrefLockedUser.js"));
+
+  Assert.strictEqual(ps.getIntPref("testPref.unlocked.int"), 333);
+  Assert.strictEqual(ps.getIntPref("testPref.locked.int"), 444);
+
+  run_next_test();
+});