1 files changed, 85 insertions, 0 deletions
diff --git a/toolkit/components/extensions/test/xpcshell/test_change_backgroundServiceWorker_enabled_pref_true.js b/toolkit/components/extensions/test/xpcshell/test_change_backgroundServiceWorker_enabled_pref_true.js
new file mode 100644
index 0000000000..06286427f5
--- /dev/null
+++ b/toolkit/components/extensions/test/xpcshell/test_change_backgroundServiceWorker_enabled_pref_true.js
@@ -0,0 +1,85 @@
+"use strict";
+
+// extensions.backgroundServiceWorker.enabled=true is set in the test manifest
+// because there is no guarantee that the pref value set at runtime takes effect
+// due to the pref being declared "mirror: once". The value of this pref is
+// frozen upon the first access to any "mirror:once" pref, and we can therefore
+// not assume the pref value to be mutable at runtime.
+const PREF_EXT_SW_ENABLED = "extensions.backgroundServiceWorker.enabled";
+const defaultPrefs = Services.prefs.getDefaultBranch("");
+
+add_task(
+  { skip_if: () => AppConstants.MOZ_WEBEXT_WEBIDL_ENABLED },
+  async function test_when_extensions_webidl_bindings_disabled() {
+    Assert.equal(
+      defaultPrefs.getBoolPref(PREF_EXT_SW_ENABLED),
+      false,
+      "The default pref value should be false"
+    );
+    Assert.ok(
+      Services.prefs.prefIsLocked(PREF_EXT_SW_ENABLED),
+      "Pref should be locked when MOZ_WEBEXT_WEBIDL_ENABLED is false"
+    );
+    // Despite the pref set to true (see comment at PREF_EXT_SW_ENABLED), the
+    // pref should be locked to false when IDL is disabled.
+    Assert.equal(
+      Services.prefs.getBoolPref(PREF_EXT_SW_ENABLED),
+      false,
+      "Pref value should be the default value"
+    );
+    Assert.equal(
+      WebExtensionPolicy.backgroundServiceWorkerEnabled,
+      false,
+      "backgroundServiceWorkerEnabled should be false"
+    );
+
+    Services.prefs.unlockPref(PREF_EXT_SW_ENABLED);
+
+    // After unlocking the pref, the pref set to true in the test manifest
+    // should apply now.
+    Assert.ok(
+      Services.prefs.getBoolPref(PREF_EXT_SW_ENABLED),
+      "After unlocking the pref, the pref can have a non-default value"
+    );
+    Assert.equal(
+      WebExtensionPolicy.backgroundServiceWorkerEnabled,
+      false,
+      "backgroundServiceWorkerEnabled is still false despite the pref flip"
+    );
+  }
+);
+
+add_task(
+  { skip_if: () => !AppConstants.MOZ_WEBEXT_WEBIDL_ENABLED },
+  async function test_when_extensions_webidl_bindings_enabled() {
+    const defaultPrefValue = defaultPrefs.getBoolPref(PREF_EXT_SW_ENABLED);
+    info(`The default pref value is ${defaultPrefValue}`);
+    Assert.ok(
+      !Services.prefs.prefIsLocked(PREF_EXT_SW_ENABLED),
+      "Pref should not be locked when MOZ_WEBEXT_WEBIDL_ENABLED is true"
+    );
+    // Note: Pref is set to true, see comment at PREF_EXT_SW_ENABLED.
+    Assert.equal(
+      Services.prefs.getBoolPref(PREF_EXT_SW_ENABLED),
+      true,
+      "Pref value should be true"
+    );
+    Assert.equal(
+      WebExtensionPolicy.backgroundServiceWorkerEnabled,
+      true,
+      "backgroundServiceWorkerEnabled should be false"
+    );
+
+    // Flip pref and test result.
+    Services.prefs.setBoolPref(PREF_EXT_SW_ENABLED, false);
+    Assert.ok(
+      !Services.prefs.getBoolPref(PREF_EXT_SW_ENABLED),
+      "The pref can be flipped to a different value"
+    );
+    Assert.equal(
+      WebExtensionPolicy.backgroundServiceWorkerEnabled,
+      true,
+      "backgroundServiceWorkerEnabled is still true despite the pref flip"
+    );
+  }
+);