1 files changed, 132 insertions, 0 deletions
diff --git a/services/sync/tests/unit/test_prefs_engine.js b/services/sync/tests/unit/test_prefs_engine.js
new file mode 100644
index 0000000000..abea0a1137
--- /dev/null
+++ b/services/sync/tests/unit/test_prefs_engine.js
@@ -0,0 +1,132 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const { getPrefsGUIDForTest } = ChromeUtils.importESModule(
+  "resource://services-sync/engines/prefs.sys.mjs"
+);
+const PREFS_GUID = getPrefsGUIDForTest();
+const { Service } = ChromeUtils.importESModule(
+  "resource://services-sync/service.sys.mjs"
+);
+
+async function cleanup(engine, server) {
+  await engine._tracker.stop();
+  await engine.wipeClient();
+  Svc.Prefs.resetBranch("");
+  Service.recordManager.clearCache();
+  await promiseStopServer(server);
+}
+
+add_task(async function test_modified_after_fail() {
+  let engine = Service.engineManager.get("prefs");
+
+  let server = await serverForFoo(engine);
+  await SyncTestingInfrastructure(server);
+
+  try {
+    // The homepage pref is synced by default.
+    _("Set homepage before first sync");
+    Services.prefs.setStringPref("browser.startup.homepage", "about:welcome");
+
+    _("First sync; create collection and pref record on server");
+    await sync_engine_and_validate_telem(engine, false);
+
+    let collection = server.user("foo").collection("prefs");
+    equal(
+      collection.cleartext(PREFS_GUID).value["browser.startup.homepage"],
+      "about:welcome",
+      "Should upload homepage in pref record"
+    );
+    ok(
+      !engine._tracker.modified,
+      "Tracker shouldn't be modified after first sync"
+    );
+
+    // Our tracker only has a `modified` flag that's reset after a
+    // successful upload. Force it to remain set by failing the
+    // upload.
+    _("Second sync; flag tracker as modified and throw on upload");
+    Services.prefs.setStringPref("browser.startup.homepage", "about:robots");
+    engine._tracker.modified = true;
+    let oldPost = collection.post;
+    collection.post = () => {
+      throw new Error("Sync this!");
+    };
+    await Assert.rejects(
+      sync_engine_and_validate_telem(engine, true),
+      ex => ex.success === false
+    );
+    ok(
+      engine._tracker.modified,
+      "Tracker should remain modified after failed sync"
+    );
+
+    _("Third sync");
+    collection.post = oldPost;
+    await sync_engine_and_validate_telem(engine, false);
+    equal(
+      collection.cleartext(PREFS_GUID).value["browser.startup.homepage"],
+      "about:robots",
+      "Should upload new homepage on third sync"
+    );
+    ok(
+      !engine._tracker.modified,
+      "Tracker shouldn't be modified again after third sync"
+    );
+  } finally {
+    await cleanup(engine, server);
+  }
+});
+
+add_task(async function test_allow_arbitrary() {
+  let engine = Service.engineManager.get("prefs");
+
+  let server = await serverForFoo(engine);
+  await SyncTestingInfrastructure(server);
+
+  try {
+    _("Create collection and pref record on server");
+    await sync_engine_and_validate_telem(engine, false);
+
+    let collection = server.user("foo").collection("prefs");
+
+    _("Insert arbitrary pref into remote record");
+    let cleartext1 = collection.cleartext(PREFS_GUID);
+    cleartext1.value.let_viruses_take_over = true;
+    collection.insert(
+      PREFS_GUID,
+      encryptPayload(cleartext1),
+      new_timestamp() + 5
+    );
+
+    _("Sync again; client shouldn't allow pref");
+    await sync_engine_and_validate_telem(engine, false);
+    ok(
+      !Services.prefs.getBoolPref("let_viruses_take_over", false),
+      "Shouldn't allow arbitrary remote prefs without control pref"
+    );
+
+    _("Sync with control pref set; client should set new pref");
+    Services.prefs.setBoolPref(
+      "services.sync.prefs.sync.let_viruses_take_over_take_two",
+      true
+    );
+
+    let cleartext2 = collection.cleartext(PREFS_GUID);
+    cleartext2.value.let_viruses_take_over_take_two = true;
+    collection.insert(
+      PREFS_GUID,
+      encryptPayload(cleartext2),
+      new_timestamp() + 5
+    );
+    // Reset the last sync time so that the engine fetches the record again.
+    await engine.setLastSync(0);
+    await sync_engine_and_validate_telem(engine, false);
+    ok(
+      Services.prefs.getBoolPref("let_viruses_take_over_take_two"),
+      "Should set arbitrary remote pref with control pref"
+    );
+  } finally {
+    await cleanup(engine, server);
+  }
+});