Fix tests

Author: FrederikBolding

packages/snaps-utils/coverage.json

@@ -1,6 +1,6 @@
 {
-  "branches": 99.53,
+  "branches": 99.76,
   "functions": 99.02,
-  "lines": 98.52,
-  "statements": 97.12
+  "lines": 98.66,
+  "statements": 97.25
 }

packages/snaps-utils/src/fs.test.ts

@@ -334,4 +334,26 @@ describe('useFileSystemCache', () => {
       value: 'foo',
     });
   });
+
+  it('skips persisting undefined', async () => {
+    const fn = useFileSystemCache('foo', 5000, async () => {
+      return undefined;
+    });
+
+    const spy = jest.spyOn(fs, 'writeFile');
+    expect(await fn()).toBeUndefined();
+
+    expect(spy).toHaveBeenCalledTimes(0);
+  });
+
+  it('skips persisting null', async () => {
+    const fn = useFileSystemCache('foo', 5000, async () => {
+      return null;
+    });
+
+    const spy = jest.spyOn(fs, 'writeFile');
+    expect(await fn()).toBeNull();
+
+    expect(spy).toHaveBeenCalledTimes(0);
+  });
 });

packages/snaps-utils/src/fs.ts

@@ -216,6 +216,11 @@ export function useFileSystemCache<Type = unknown>(
 
     const value = await fn();
 
+    // Null or undefined is not persisted.
+    if (value === null || value === undefined) {
+      return value;
+    }
+
     try {
       await fs.mkdir(pathUtils.dirname(filePath), { recursive: true });
 

packages/snaps-utils/src/manifest/validators/production-platform-version.test.ts

@@ -1,6 +1,8 @@
 import type { SemVerVersion } from '@metamask/utils';
 import assert from 'assert';
+import { promises as fs } from 'fs';
 import fetchMock from 'jest-fetch-mock';
+import { join } from 'path';
 
 import { productionPlatformVersion } from './production-platform-version';
 import { getMockSnapFiles, getSnapManifest } from '../../test-utils';
@@ -18,11 +20,19 @@ const MOCK_PACKAGE_JSON = JSON.stringify({
   },
 });
 
+const CACHE_PATH = join(process.cwd(), 'node_modules/.cache');
+
 describe('productionPlatformVersion', () => {
   beforeAll(() => {
     fetchMock.enableMocks();
   });
 
+  beforeEach(async () => {
+    fetchMock.resetMocks();
+
+    await fs.rm(CACHE_PATH, { recursive: true, force: true });
+  });
+
   afterAll(() => {
     fetchMock.disableMocks();
   });
@@ -98,7 +108,7 @@ describe('productionPlatformVersion', () => {
   });
 
   it('does nothing if the request to check the production version fails', async () => {
-    fetchMock.mockResponse('', { status: 404 });
+    fetchMock.mockResponse(async () => ({ status: 404, body: 'Not found' }));
 
     const report = jest.fn();
     assert(productionPlatformVersion.semanticCheck);