workerForceExit e2e test

e2e/Utils.ts

@@ -89,6 +89,21 @@ export const writeFiles = (
   });
 };
 
+const NUMBER_OF_TESTS_TO_FORCE_USING_WORKERS = 25;
+/**
+ * Forces Jest to use workers by generating many test files to run.
+ * Slow and modifies the test output. Use sparingly.
+ */
+export const generateTestFilesToForceUsingWorkers = () => {
+  const testFiles = {};
+  for (let i = 0; i <= NUMBER_OF_TESTS_TO_FORCE_USING_WORKERS; i++) {
+    testFiles[`__tests__/test${i}.test.js`] = `
+      test('test ${i}', () => {});
+    `;
+  }
+  return testFiles;
+};
+
 export const copyDir = (src: string, dest: string) => {
   const srcStat = fs.lstatSync(src);
   if (srcStat.isDirectory()) {

e2e/__tests__/fatalWorkerError.test.ts

@@ -7,31 +7,28 @@
 
 import path from 'path';
 import os from 'os';
-import {cleanup, writeFiles} from '../Utils';
+import {
+  cleanup,
+  generateTestFilesToForceUsingWorkers,
+  writeFiles,
+} from '../Utils';
 import runJest from '../runJest';
 
 const DIR = path.resolve(os.tmpdir(), 'fatal-worker-error');
 
 beforeEach(() => cleanup(DIR));
 afterAll(() => cleanup(DIR));
 
-const NUMBER_OF_TESTS_TO_FORCE_USING_WORKERS = 25;
-
 test('fails a test that terminates the worker with a fatal error', () => {
   const testFiles = {
+    ...generateTestFilesToForceUsingWorkers(),
     '__tests__/fatalWorkerError.test.js': `
       test('fatal worker error', () => {
         process.exit(134);
       });
     `,
   };
 
-  for (let i = 0; i <= NUMBER_OF_TESTS_TO_FORCE_USING_WORKERS; i++) {
-    testFiles[`__tests__/test${i}.test.js`] = `
-      test('test ${i}', () => {});
-    `;
-  }
-
   writeFiles(DIR, {
     ...testFiles,
     'package.json': '{}',

e2e/__tests__/workerForceExit.test.ts

@@ -0,0 +1,62 @@
+import {tmpdir} from 'os';
+import {resolve} from 'path';
+import findProcess from 'find-process';
+
+import {
+  cleanup,
+  generateTestFilesToForceUsingWorkers,
+  writeFiles,
+} from '../Utils';
+import runJest from '../runJest';
+
+const DIR = resolve(tmpdir(), 'worker-force-exit');
+
+beforeEach(() => cleanup(DIR));
+const testFiles = {
+  ...generateTestFilesToForceUsingWorkers(),
+  'package.json': `{
+      "testEnvironment": "node"
+  }`,
+};
+afterEach(() => cleanup(DIR));
+
+const verifyNumPassed = stderr => {
+  const numberOfTestsPassed = (stderr.match(/\bPASS\b/g) || []).length;
+  // assuming -1 because of package.json, but +1 because of the individual test file
+  expect(numberOfTestsPassed).toBe(Object.keys(testFiles).length);
+};
+
+test('prints a warning if a worker is force exited', () => {
+  writeFiles(DIR, {
+    ...testFiles,
+    '__tests__/simple.test.js': `
+      test('t', () => {
+        require('http').createServer().listen(0);
+      });
+    `,
+  });
+  const {status, stderr, stdout} = runJest(DIR, ['--maxWorkers=2']);
+
+  expect(status).toBe(0);
+  verifyNumPassed(stderr);
+  expect(stdout).toContain('A worker process has failed to exit gracefully');
+});
+
+test('force exits a worker that fails to exit gracefully', async () => {
+  writeFiles(DIR, {
+    ...testFiles,
+    '__tests__/timeoutKilled.test.js': `
+      test('t', () => {
+        require('http').createServer().listen(0);
+        console.error('pid: ' + process.pid);
+      });
+    `,
+  });
+  const {status, stderr} = runJest(DIR, ['--maxWorkers=2']);
+
+  expect(status).toBe(0);
+  verifyNumPassed(stderr);
+
+  const [pid] = /pid: \d+/.exec(stderr);
+  expect(await findProcess('pid', pid)).toHaveLength(0);
+});

package.json

@@ -39,6 +39,7 @@
     "eslint-plugin-react": "^7.1.0",
     "eslint-plugin-relay": "~0.0.19",
     "execa": "^1.0.0",
+    "find-process": "^1.4.1",
     "glob": "^7.1.1",
     "graceful-fs": "^4.1.15",
     "isbinaryfile": "^4.0.0",

yarn.lock

@@ -5908,6 +5908,15 @@ find-cache-dir@^2.0.0:
     make-dir "^1.0.0"
     pkg-dir "^3.0.0"
 
+find-process@^1.4.1:
+  version "1.4.1"
+  resolved "https://registry.yarnpkg.com/find-process/-/find-process-1.4.1.tgz#628c576a494d1525a27673fb26c77af90db5db02"
+  integrity sha512-RkYWDeukxEoDKUyocqMGKAYuwhSwq77zL99gCqhX9czWon3otdlzihJ0MSZ6YWNKHyvS/MN2YR4+RGYOuIEANg==
+  dependencies:
+    chalk "^2.0.1"
+    commander "^2.11.0"
+    debug "^2.6.8"
+
 find-up@^1.0.0:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/find-up/-/find-up-1.1.2.tgz#6b2e9822b1a2ce0a60ab64d610eccad53cb24d0f"