1 files changed, 38 insertions, 0 deletions
diff --git a/toolkit/mozapps/update/tests/unit_aus_update/verifyChannelPrefsFile.js b/toolkit/mozapps/update/tests/unit_aus_update/verifyChannelPrefsFile.js
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+++ b/toolkit/mozapps/update/tests/unit_aus_update/verifyChannelPrefsFile.js
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+/* 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/.
+ */
+
+/**
+ * This test exists solely to ensure that channel-prefs.js is not changed.
+ * If it does get changed, it will cause a variation of Bug 1431342.
+ * To summarize, our updater doesn't update that file. But, on macOS, it is
+ * still used to compute the application's signature. This means that if Firefox
+ * updates and that file has been changed, the signature no will no longer
+ * validate.
+ */
+
+const expectedChannelPrefsContents = `/* 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/. */
+//
+// This pref is in its own file for complex reasons. See the comment in
+// browser/app/Makefile.in, bug 756325, and bug 1431342 for details. Do not add
+// other prefs to this file.
+
+pref("app.update.channel", "${UpdateUtils.UpdateChannel}");
+`;
+
+async function run_test() {
+  let channelPrefsFile = Services.dirsvc.get("GreD", Ci.nsIFile);
+  channelPrefsFile.append("defaults");
+  channelPrefsFile.append("pref");
+  channelPrefsFile.append("channel-prefs.js");
+
+  const contents = await IOUtils.readUTF8(channelPrefsFile.path);
+  Assert.equal(
+    contents,
+    expectedChannelPrefsContents,
+    "Channel Prefs file should should not change"
+  );
+}