refactor: remove test logic from lib

jest.config.js

@@ -0,0 +1,7 @@
+/** @type {import('ts-jest').JestConfigWithTsJest} **/
+module.exports = {
+  testEnvironment: 'node',
+  transform: {
+    '^.+.tsx?$': ['ts-jest', {}]
+  }
+}

package.json

@@ -15,12 +15,14 @@
   },
   "devDependencies": {
     "@types/github-url-to-object": "^4.0.1",
+    "@types/jest": "^29.5.14",
     "@types/ms": "^0.7.31",
     "electron": "^22.0.0",
     "jest": "^29.0.0",
     "prettier": "^3.0.3",
     "standard": "^14.3.4",
     "standard-markdown": "^6.0.0",
+    "ts-jest": "^29.2.5",
     "typescript": "^4.9.4"
   },
   "scripts": {

src/index.ts

@@ -1,12 +1,13 @@
-import assert from 'assert';
 import ms from 'ms';
 import gh from 'github-url-to-object';
-import path from 'path';
-import fs from 'fs';
-import os from 'os';
-import { format } from 'util';
 
-import { app } from 'electron';
+import assert from 'node:assert';
+import fs from 'node:fs';
+import os from 'node:os';
+import path from 'node:path';
+import { format } from 'node:util';
+
+import { app, autoUpdater, dialog } from 'electron';
 
 export interface ILogger {
   log(message: string): void;
@@ -100,12 +101,15 @@ export function updateElectronApp(opts: IUpdateElectronAppOptions = {}) {
     return;
   }
 
-  if (safeOpts.electron.app.isReady()) initUpdater(safeOpts);
-  else app.on('ready', () => initUpdater(safeOpts));
+  if (app.isReady()) {
+    initUpdater(safeOpts);
+  } else {
+    app.on('ready', () => initUpdater(safeOpts));
+  }
 }
 
 function initUpdater(opts: ReturnType<typeof validateInput>) {
-  const { updateSource, updateInterval, logger, electron } = opts;
+  const { updateSource, updateInterval, logger } = opts;
 
   // exit early on unsupported platforms, e.g. `linux`
   if (!supportedPlatforms.includes(process?.platform)) {
@@ -115,7 +119,6 @@ function initUpdater(opts: ReturnType<typeof validateInput>) {
     return;
   }
 
-  const { app, autoUpdater, dialog } = electron;
   let feedURL: string;
   let serverType: 'default' | 'json' = 'default';
   switch (updateSource.type) {
@@ -195,8 +198,8 @@ function initUpdater(opts: ReturnType<typeof validateInput>) {
   }, ms(updateInterval));
 }
 
-function guessRepo(electron: typeof Electron.Main) {
-  const pkgBuf = fs.readFileSync(path.join(electron.app.getAppPath(), 'package.json'));
+function guessRepo() {
+  const pkgBuf = fs.readFileSync(path.join(app.getAppPath(), 'package.json'));
   const pkg = JSON.parse(pkgBuf.toString());
   const repoString = pkg.repository?.url || pkg.repository;
   const repoObject = gh(repoString);
@@ -213,15 +216,12 @@ function validateInput(opts: IUpdateElectronAppOptions) {
   };
   const { host, updateInterval, logger, notifyUser } = Object.assign({}, defaults, opts);
 
-  // allows electron to be mocked in tests
-  const electron: typeof Electron.Main = (opts as any).electron || require('electron');
-
   let updateSource = opts.updateSource;
   // Handle migration from old properties + default to update service
   if (!updateSource) {
     updateSource = {
       type: UpdateSourceType.ElectronPublicUpdateService,
-      repo: opts.repo || guessRepo(electron),
+      repo: opts.repo || guessRepo(),
       host,
     };
   }
@@ -254,5 +254,5 @@ function validateInput(opts: IUpdateElectronAppOptions) {
 
   assert(logger && typeof logger.log, 'function');
 
-  return { updateSource, updateInterval, logger, electron, notifyUser };
+  return { updateSource, updateInterval, logger, notifyUser };
 }

test/__mocks__/electron.ts

@@ -1,5 +1,33 @@
+import os from 'node:os';
+
 module.exports = {
   app: {
+    getVersion: () => {
+      return '1.2.3';
+    },
+    isReady: () => true,
+    on: () => {
+      /* no-op */
+    },
+    getAppPath: () => {
+      return os.tmpdir();
+    },
     isPackaged: true,
   },
+  autoUpdater: {
+    checkForUpdates: () => {
+      /* no-op */
+    },
+    on: () => {
+      /* no-op */
+    },
+    setFeedURL: () => {
+      /* no-op */
+    },
+  },
+  dialog: {
+    showMessageBox: () => {
+      /* no-op */
+    },
+  },
 };

test/index.test.ts

@@ -0,0 +1,61 @@
+import fs from 'node:fs';
+import os from 'node:os';
+import path from 'node:path';
+
+import { updateElectronApp } from '..';
+const repo = 'some-owner/some-repo';
+
+jest.mock('electron');
+
+beforeEach(() => {
+  jest.useFakeTimers();
+});
+
+describe('updateElectronApp', () => {
+  it('is a function', () => {
+    expect(typeof updateElectronApp).toBe('function');
+  });
+
+  describe('repository', () => {
+    const tmpdir = os.tmpdir();
+    const packageJson = path.join(tmpdir, 'package.json');
+    beforeAll(() => {
+      fs.writeFileSync(packageJson, JSON.stringify({}));
+    });
+
+    it('is required', () => {
+      expect(() => {
+        updateElectronApp();
+      }).toThrow("repo not found. Add repository string to your app's package.json file");
+    });
+
+    it('from opts', () => {
+      updateElectronApp({ repo: 'foo/bar' });
+    });
+
+    it('from package.json', () => {
+      fs.writeFileSync(packageJson, JSON.stringify({ repository: 'foo/bar' }));
+      updateElectronApp();
+    });
+
+    afterAll(() => {
+      fs.rmSync(packageJson);
+    });
+  });
+
+  describe('host', () => {
+    it('must a valid HTTPS URL', () => {
+      expect(() => {
+        updateElectronApp({ repo, host: 'http://example.com' });
+      }).toThrow('host must be a valid HTTPS URL');
+    });
+  });
+
+  describe('updateInterval', () => {
+    it('must be 5 minutes or more', () => {
+      expect(() => {
+        updateElectronApp({ repo, updateInterval: '20 seconds' });
+      }).toThrow('updateInterval must be `5 minutes` or more');
+    });
+  });
+});