feat(jest-config): openHandlesTimeout config option (#13875)

Author: robhogan

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - `[jest-changed-files]` Support Sapling ([#13941](https://github.com/facebook/jest/pull/13941))
 - `[jest-cli, jest-config, @jest/core, jest-haste-map, @jest/reporters, jest-runner, jest-runtime, @jest/types]` Add `workerThreads` configuration option to allow using [worker threads](https://nodejs.org/dist/latest/docs/api/worker_threads.html) for parallelization ([#13939](https://github.com/facebook/jest/pull/13939))
+- `[jest-config]` Add `openHandlesTimeout` option to configure possible open handles warning. ([#13875](https://github.com/facebook/jest/pull/13875))
 - `[@jest/create-cache-key-function]` Allow passing `length` argument to `createCacheKey()` function and set its default value to `16` on Windows ([#13827](https://github.com/facebook/jest/pull/13827))
 - `[jest-message-util]` Add support for [AggregateError](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError) ([#13946](https://github.com/facebook/jest/pull/13946))
 - `[jest-worker]` Add `start` method to worker farms ([#13937](https://github.com/facebook/jest/pull/13937))

docs/CLI.md

@@ -310,6 +310,10 @@ Activates notifications for test results. Good for when you don't want your cons
 
 Alias: `-o`. Attempts to identify which tests to run based on which files have changed in the current repository. Only works if you're running tests in a git/hg repository at the moment and requires a static dependency graph (ie. no dynamic requires).
 
+### `--openHandlesTimeout=<milliseconds>`
+
+When `--detectOpenHandles` and `--forceExit` are _disabled_, Jest will print a warning if the process has not exited cleanly after this number of milliseconds. A value of `0` disables the warning. Defaults to `1000`.
+
 ### `--outputFile=<filename>`
 
 Write test results to a file when the `--json` option is also specified. The returned JSON structure is documented in [testResultsProcessor](Configuration.md#testresultsprocessor-string).

docs/Configuration.md

@@ -1078,6 +1078,12 @@ Specifies notification mode. Requires `notify: true`.
 - `success-change`: send a notification when tests pass or once when it fails.
 - `failure-change`: send a notification when tests fail or once when it passes.
 
+### `openHandlesTimeout` \[number]
+
+Default: `1000`
+
+Print a warning indicating that there are probable open handles if Jest does not exit cleanly this number of milliseconds after it completes. Use `0` to disable the warning.
+
 ### `preset` \[string]
 
 Default: `undefined`

e2e/__tests__/__snapshots__/detectOpenHandles.ts.snap

@@ -7,7 +7,13 @@ exports[`prints message about flag on forceExit 1`] = `"Force exiting Jest: Have
 exports[`prints message about flag on slow tests 1`] = `
 "Jest did not exit one second after the test run has completed.
 
-This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with \`--detectOpenHandles\` to troubleshoot this issue."
+'This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with \`--detectOpenHandles\` to troubleshoot this issue."
+`;
+
+exports[`prints message about flag on slow tests with a custom timeout 1`] = `
+"Jest did not exit 0.5 seconds after the test run has completed.
+
+'This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with \`--detectOpenHandles\` to troubleshoot this issue."
 `;
 
 exports[`prints out info about open handlers 1`] = `

e2e/__tests__/__snapshots__/showConfig.test.ts.snap

@@ -44,6 +44,7 @@ exports[`--showConfig outputs config info and exits 1`] = `
       ],
       "moduleNameMapper": [],
       "modulePathIgnorePatterns": [],
+      "openHandlesTimeout": 1000,
       "prettierPath": "prettier",
       "resetMocks": false,
       "resetModules": false,
@@ -121,6 +122,7 @@ exports[`--showConfig outputs config info and exits 1`] = `
     "notifyMode": "failure-change",
     "onlyChanged": false,
     "onlyFailures": false,
+    "openHandlesTimeout": 1000,
     "passWithNoTests": false,
     "projects": [],
     "rootDir": "<<REPLACED_ROOT_DIR>>",

e2e/__tests__/detectOpenHandles.ts

@@ -29,6 +29,20 @@ it('prints message about flag on slow tests', async () => {
   expect(textAfterTest).toMatchSnapshot();
 });
 
+it('prints message about flag on slow tests with a custom timeout', async () => {
+  const run = runContinuous('detect-open-handles', [
+    'outside',
+    '--openHandlesTimeout=500',
+  ]);
+  await run.waitUntil(({stderr}) =>
+    stderr.includes('Jest did not exit 0.5 seconds'),
+  );
+  const {stderr} = await run.end();
+  const textAfterTest = getTextAfterTest(stderr);
+
+  expect(textAfterTest).toMatchSnapshot();
+});
+
 it('prints message about flag on forceExit', async () => {
   const run = runContinuous('detect-open-handles', ['outside', '--forceExit']);
   await run.waitUntil(({stderr}) => stderr.includes('Force exiting Jest'));

packages/jest-cli/src/args.ts

@@ -423,6 +423,12 @@ export const options: {[key: string]: Options} = {
     description: 'Run tests that failed in the previous execution.',
     type: 'boolean',
   },
+  openHandlesTimeout: {
+    description:
+      'Print a warning about probable open handles if Jest does not exit ' +
+      'cleanly after this number of milliseconds. `0` to disable.',
+    type: 'number',
+  },
   outputFile: {
     description:
       'Write test results to a file when the --json option is ' +

packages/jest-cli/src/run.ts

@@ -132,18 +132,24 @@ const readResultsAndExit = (
     }
 
     exit(code);
-  } else if (!globalConfig.detectOpenHandles) {
+  } else if (
+    !globalConfig.detectOpenHandles &&
+    globalConfig.openHandlesTimeout !== 0
+  ) {
+    const timeout = globalConfig.openHandlesTimeout;
     setTimeout(() => {
       console.warn(
         chalk.yellow.bold(
-          'Jest did not exit one second after the test run has completed.\n\n',
+          `Jest did not exit ${
+            timeout === 1000 ? 'one second' : `${timeout / 1000} seconds`
+          } after the test run has completed.\n\n'`,
         ) +
           chalk.yellow(
             'This usually means that there are asynchronous operations that ' +
               "weren't stopped in your tests. Consider running Jest with " +
               '`--detectOpenHandles` to troubleshoot this issue.',
           ),
       );
-    }, 1000).unref();
+    }, timeout).unref();
   }
 };

packages/jest-config/src/Defaults.ts

@@ -60,6 +60,7 @@ const defaultOptions: Config.DefaultOptions = {
   noStackTrace: false,
   notify: false,
   notifyMode: 'failure-change',
+  openHandlesTimeout: 1000,
   passWithNoTests: false,
   prettierPath: 'prettier',
   resetMocks: false,

packages/jest-config/src/ValidConfig.ts

@@ -116,6 +116,7 @@ export const initialOptions: Config.InitialOptions = {
   notifyMode: 'failure-change',
   onlyChanged: false,
   onlyFailures: false,
+  openHandlesTimeout: 1000,
   passWithNoTests: false,
   preset: 'react-native',
   prettierPath: '<rootDir>/node_modules/prettier',
@@ -262,6 +263,7 @@ export const initialProjectOptions: Config.InitialProjectOptions = {
   },
   modulePathIgnorePatterns: ['<rootDir>/build/'],
   modulePaths: ['/shared/vendor/modules'],
+  openHandlesTimeout: 1000,
   preset: 'react-native',
   prettierPath: '<rootDir>/node_modules/prettier',
   resetMocks: false,