test(browser): add test case for cjs import (vitest-dev#4690)

test/browser/cjs-lib/index.js

@@ -0,0 +1,7 @@
+module.exports = {
+  a: 'a',
+  b: 'b',
+  object: {
+    h: 'h',
+  },
+}

test/browser/cjs-lib/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "@vitest/cjs-lib",
+  "type": "commonjs",
+  "exports": {
+    "default": "./index.js"
+  }
+}

test/browser/package.json

@@ -10,6 +10,7 @@
   },
   "devDependencies": {
     "@vitest/browser": "workspace:*",
+    "@vitest/cjs-lib": "link:./cjs-lib",
     "execa": "^7.1.1",
     "safaridriver": "^0.0.4",
     "vitest": "workspace:*"

test/browser/specs/runner.test.mjs

@@ -24,8 +24,8 @@ const passedTests = getPassed(browserResultJson.testResults)
 const failedTests = getFailed(browserResultJson.testResults)
 
 await test('tests are actually running', async () => {
-  assert.ok(browserResultJson.testResults.length === 8, 'Not all the tests have been run')
-  assert.ok(passedTests.length === 7, 'Some tests failed')
+  assert.ok(browserResultJson.testResults.length === 9, 'Not all the tests have been run')
+  assert.ok(passedTests.length === 8, 'Some tests failed')
   assert.ok(failedTests.length === 1, 'Some tests have passed but should fail')
 
   assert.doesNotMatch(stderr, /Unhandled Error/, 'doesn\'t have any unhandled errors')

test/browser/test/cjs-lib.test.ts

@@ -0,0 +1,21 @@
+import { expect, test } from 'vitest'
+import cjsDefault, { a as cjsNamed } from '@vitest/cjs-lib'
+import * as cjsNamespace from '@vitest/cjs-lib'
+
+test('cjs namespace import', () => {
+  expect(cjsNamespace).toEqual({
+    a: 'a',
+    b: 'b',
+    object: {
+      h: 'h',
+    },
+  })
+})
+
+test('cjs named import', () => {
+  expect(cjsNamed).toEqual('a')
+})
+
+test('cjs default import not supported when slowHijackESM', () => {
+  expect(cjsDefault).toBeUndefined()
+})

test/browser/vitest.config.mts

@@ -7,6 +7,9 @@ const dir = dirname(fileURLToPath(import.meta.url))
 function noop() {}
 
 export default defineConfig({
+  optimizeDeps: {
+    include: ['@vitest/cjs-lib'],
+  },
   test: {
     include: ['test/**.test.{ts,js}'],
     browser: {