Parallelize test-electron

ts/windows/main/preload_test.ts

@@ -8,7 +8,9 @@ import { ipcRenderer as ipc } from 'electron';
 import { sync } from 'fast-glob';
 
 // eslint-disable-next-line import/no-extraneous-dependencies
-import { assert, config as chaiConfig } from 'chai';
+import chai, { assert, config as chaiConfig } from 'chai';
+// eslint-disable-next-line import/no-extraneous-dependencies
+import chaiAsPromised from 'chai-as-promised';
 // eslint-disable-next-line import/no-extraneous-dependencies
 import { reporters, type MochaOptions } from 'mocha';
 
@@ -19,6 +21,8 @@ import { initializeRedux } from '../../state/initializeRedux';
 import * as Stickers from '../../types/Stickers';
 import { ThemeType } from '../../types/Util';
 
+chai.use(chaiAsPromised);
+
 // Show actual objects instead of abbreviated errors
 chaiConfig.truncateThreshold = 0;
 
@@ -47,6 +51,8 @@ window.assert = assert;
 //   code in `test/test.js`.
 
 const setup: MochaOptions = {};
+let worker = 0;
+let workerCount = 1;
 
 {
   const { values } = parseArgs({
@@ -55,6 +61,12 @@ const setup: MochaOptions = {};
       grep: {
         type: 'string',
       },
+      worker: {
+        type: 'string',
+      },
+      'worker-count': {
+        type: 'string',
+      },
     },
     strict: false,
   });
@@ -62,6 +74,12 @@ const setup: MochaOptions = {};
   if (typeof values.grep === 'string') {
     setup.grep = values.grep;
   }
+  if (typeof values.worker === 'string') {
+    worker = parseInt(values.worker, 10);
+  }
+  if (typeof values['worker-count'] === 'string') {
+    workerCount = parseInt(values['worker-count'], 10);
+  }
 }
 
 window.testUtilities = {
@@ -104,10 +122,17 @@ window.testUtilities = {
 
   prepareTests() {
     console.log('Preparing tests...');
-    sync('../../test-{both,electron}/**/*_test.js', {
+    const files = sync('../../test-{both,electron}/**/*_test.js', {
       absolute: true,
       cwd: __dirname,
-    }).forEach(require);
+    });
+
+    for (let i = 0; i < files.length; i += 1) {
+      if (i % workerCount === worker) {
+        // eslint-disable-next-line import/no-dynamic-require, global-require
+        require(files[i]);
+      }
+    }
   },
 };