Remove debug and inspect flags from the arguments sent to the chi…

…ld (#5068)

* Remove `debug` and `inspect` flags from the arguments sent to the child

* address PR comments

CHANGELOG.md

@@ -2,13 +2,16 @@
 
 ### Fixes
 
+* `[jest-worker]` Remove `debug` and `inspect` flags from the arguments sent to
+  the child ([#5068](https://github.com/facebook/jest/pull/5068))
 * `[jest-config]` Use all `--testPathPattern` and `<regexForTestFiles>` args in
-  `testPathPattern`([#5066](https://github.com/facebook/jest/pull/5066))
-* `[jest-cli]` Do not support `--watch` inside non-version-controlled environments
-  ([#5060](https://github.com/facebook/jest/pull/5060))
+  `testPathPattern` ([#5066](https://github.com/facebook/jest/pull/5066))
+* `[jest-cli]` Do not support `--watch` inside non-version-controlled
+  environments ([#5060](https://github.com/facebook/jest/pull/5060))
 * `[jest-config]` Escape Windows path separator in testPathPattern CLI arguments
   ([#5054](https://github.com/facebook/jest/pull/5054)
-* `[jest-jasmine]` Register sourcemaps as node environment to improve performance with jsdom ([#5045](https://github.com/facebook/jest/pull/5045))
+* `[jest-jasmine]` Register sourcemaps as node environment to improve
+  performance with jsdom ([#5045](https://github.com/facebook/jest/pull/5045))
 * `[pretty-format]` Do not call toJSON recursively
   ([#5044](https://github.com/facebook/jest/pull/5044))
 * `[pretty-format]` Fix errors when identity-obj-proxy mocks CSS Modules
@@ -66,8 +69,8 @@
 
 ### Features
 
-* `[jest-config]` Add `testEnvironmentOptions` to apply to jsdom options or node context.
-  ([#5003](https://github.com/facebook/jest/pull/5003))
+* `[jest-config]` Add `testEnvironmentOptions` to apply to jsdom options or node
+  context. ([#5003](https://github.com/facebook/jest/pull/5003))
 * `[jest-jasmine2]` Update Timeout error message to `jest.timeout` and display
   current timeout value ([#4990](https://github.com/facebook/jest/pull/4990))
 * `[jest-runner]` Enable experimental detection of leaked contexts

docs/GlobalAPI.md

@@ -19,8 +19,8 @@ environment. You don't have to require or import anything to use them.
 Runs a function after all the tests in this file have completed. If the function
 returns a promise, Jest waits for that promise to resolve before continuing.
 
-Optionally, you can provide a `timeout` (in milliseconds) for specifying how long to wait
-before aborting. _Note: The default timeout is 5 seconds._
+Optionally, you can provide a `timeout` (in milliseconds) for specifying how
+long to wait before aborting. _Note: The default timeout is 5 seconds._
 
 This is often useful if you want to clean up some global setup state that is
 shared across tests.
@@ -66,8 +66,8 @@ Runs a function after each one of the tests in this file completes. If the
 function returns a promise, Jest waits for that promise to resolve before
 continuing.
 
-Optionally, you can provide a `timeout` (in milliseconds) for specifying how long to wait
-before aborting. _Note: The default timeout is 5 seconds._
+Optionally, you can provide a `timeout` (in milliseconds) for specifying how
+long to wait before aborting. _Note: The default timeout is 5 seconds._
 
 This is often useful if you want to clean up some temporary state that is
 created by each test.
@@ -112,8 +112,8 @@ If you want to run some cleanup just once, after all of the tests run, use
 Runs a function before any of the tests in this file run. If the function
 returns a promise, Jest waits for that promise to resolve before running tests.
 
-Optionally, you can provide a `timeout` (in milliseconds) for specifying how long to wait
-before aborting. _Note: The default timeout is 5 seconds._
+Optionally, you can provide a `timeout` (in milliseconds) for specifying how
+long to wait before aborting. _Note: The default timeout is 5 seconds._
 
 This is often useful if you want to set up some global state that will be used
 by many tests.
@@ -157,8 +157,8 @@ Runs a function before each of the tests in this file runs. If the function
 returns a promise, Jest waits for that promise to resolve before running the
 test.
 
-Optionally, you can provide a `timeout` (in milliseconds) for specifying how long to wait
-before aborting. _Note: The default timeout is 5 seconds._
+Optionally, you can provide a `timeout` (in milliseconds) for specifying how
+long to wait before aborting. _Note: The default timeout is 5 seconds._
 
 This is often useful if you want to reset some global state that will be used by
 many tests.
@@ -327,8 +327,9 @@ test('did not rain', () => {
 ```
 
 The first argument is the test name; the second argument is a function that
-contains the expectations to test. The third argument (optional) is `timeout` (in milliseconds)
-for specifying how long to wait before aborting. _Note: The default timeout is 5 seconds._
+contains the expectations to test. The third argument (optional) is `timeout`
+(in milliseconds) for specifying how long to wait before aborting. _Note: The
+default timeout is 5 seconds._
 
 > Note: If a **promise is returned** from `test`, Jest will wait for the promise
 > to resolve before letting the test complete. Jest will also wait if you
@@ -358,8 +359,8 @@ When you are debugging a large codebase, you will often only want to run a
 subset of tests. You can use `.only` to specify which tests are the only ones
 you want to run.
 
-Optionally, you can provide a `timeout` (in milliseconds) for specifying how long to wait
-before aborting. _Note: The default timeout is 5 seconds._
+Optionally, you can provide a `timeout` (in milliseconds) for specifying how
+long to wait before aborting. _Note: The default timeout is 5 seconds._
 
 For example, let's say you had these tests:
 

packages/jest-worker/README.md

@@ -87,8 +87,8 @@ to `3`, pass `Infinity` to allow endless retries.
 #### `forkOptions: Object` (optional)
 
 Allow customizing all options passed to `childProcess.fork`. By default, some
-values are set (`cwd` and `env`), but you can override them and customize the
-rest. For a list of valid values, check
+values are set (`cwd`, `env` and `execArgv`), but you can override them and
+customize the rest. For a list of valid values, check
 [the Node documentation](https://nodejs.org/api/child_process.html#child_process_child_process_fork_modulepath_args_options).
 
 #### `computeWorkerKey: (method: string, ...args: Array<any>) => ?string` (optional)

packages/jest-worker/src/__tests__/worker.test.js

@@ -21,9 +21,11 @@ import {
 let Worker;
 let forkInterface;
 let childProcess;
+let originalExecArgv;
 
 beforeEach(() => {
   jest.mock('child_process');
+  originalExecArgv = process.execArgv;
 
   childProcess = require('child_process');
   childProcess.fork.mockImplementation(() => {
@@ -41,14 +43,18 @@ beforeEach(() => {
 
 afterEach(() => {
   jest.resetModules();
+  process.execArgv = originalExecArgv;
 });
 
 it('passes fork options down to child_process.fork, adding the defaults', () => {
   const child = require.resolve('../child');
+
+  process.execArgv = ['--inspect', '-p'];
+
   new Worker({
     forkOptions: {
       cwd: '/tmp',
-      execArgv: ['--no-warnings'],
+      execPath: 'hello',
     },
     maxRetries: 3,
     workerPath: '/tmp/foo/bar/baz.js',
@@ -58,7 +64,8 @@ it('passes fork options down to child_process.fork, adding the defaults', () =>
   expect(childProcess.fork.mock.calls[0][1]).toEqual({
     cwd: '/tmp', // Overridden default option.
     env: process.env, // Default option.
-    execArgv: ['--no-warnings'], // Added option.
+    execArgv: ['-p'], // Filtered option.
+    execPath: 'hello', // Added option.
     silent: true, // Default option.
   });
 });

packages/jest-worker/src/worker.js

@@ -80,6 +80,8 @@ export default class {
         {
           cwd: process.cwd(),
           env: process.env,
+          // suppress --debug / --inspect flags while preserving others (like --harmony)
+          execArgv: process.execArgv.filter(v => !/^--(debug|inspect)/.test(v)),
           silent: true,
         },
         this._options.forkOptions,