test: Add tests for main window hardening

We try to stub/mock the Electron API to make sure the test environment
is as close to the runtime environment for this security critical code.

Signed-off-by: Kristóf Marussy <kristof@marussy.com>

3 files changed, 38 insertions, 2 deletions

diff --git a/packages/test-utils/package.json b/packages/test-utils/package.json
index 9270af2..2f0610a 100644
--- a/packages/test-utils/package.json
+++ b/packages/test-utils/package.json
@@ -12,6 +12,7 @@
   "dependencies": {
     "@types/jest": "^27.4.0",
     "jest": "^27.4.7",
-    "jest-each": "^27.4.6"
+    "jest-each": "^27.4.6",
+    "type-fest": "^2.11.0"
   }
 }
diff --git a/packages/test-utils/src/fake.ts b/packages/test-utils/src/fake.ts
new file mode 100644
index 0000000..57cfa88
--- /dev/null
+++ b/packages/test-utils/src/fake.ts
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C)  2022 Kristóf Marussy <kristof@marussy.com>
+ *
+ * This file is part of Sophie.
+ *
+ * Sophie is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import type { PartialDeep } from 'type-fest';
+
+/**
+ * Creates a fake object with some properties possibly missing.
+ *
+ * Interacting with missing properties will cause a test failure due to
+ * trying to access members of `undefined.`
+ *
+ * @param partialImplementation The partial fake implementation.
+ * @returns The same value as `partialImplementation` but with a casted type.
+ */
+export default function fake<T>(partialImplementation: PartialDeep<T>): T {
+  return partialImplementation as T;
+}
diff --git a/packages/test-utils/src/index.ts b/packages/test-utils/src/index.ts
index 5de84f1..1543c6e 100644
--- a/packages/test-utils/src/index.ts
+++ b/packages/test-utils/src/index.ts
@@ -18,5 +18,6 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-// eslint-disable-next-line import/prefer-default-export -- More exports will be added here.
 export { default as each } from './each';
+
+export { default as fake } from './fake';