Support dashed args

CHANGELOG.md

@@ -80,6 +80,7 @@
 - `[jest-haste-map]` Remove legacy condition for duplicate module detection ([#7333](https://github.com/facebook/jest/pull/7333))
 - `[jest-haste-map]` Fix `require` detection with trailing commas and ignore `import typeof` modules ([#7385](https://github.com/facebook/jest/pull/7385))
 - `[jest-cli]` Fix to set prettierPath via config file ([#7412](https://github.com/facebook/jest/pull/7412))
+- `[jest-cli]` Support dashed args ([#7497](https://github.com/facebook/jest/pull/7497))
 
 ### Chore & Maintenance
 

docs/CLI.md

@@ -81,6 +81,21 @@ you can use:
 npm test -- -u -t="ColorPicker"
 ```
 
+## Camelcase & dashed args support
+
+Jest supports both camelcase and dashed arg formats. The following examples will have equal result:
+
+```bash
+jest --collect-coverage
+jest --collectCoverage
+```
+
+Arguments can also be mixed:
+
+```bash
+jest --update-snapshot --detectOpenHandles
+```
+
 ## Options
 
 _Note: CLI options take precedence over values from the [Configuration](Configuration.md)._

e2e/__tests__/supports-dashed-args.js

@@ -0,0 +1,63 @@
+/**
+ * Copyright (c) 2018-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ */
+
+'use strict';
+
+import path from 'path';
+import runJest from '../runJest';
+
+const consoleDir = path.resolve(__dirname, '../console');
+const eachDir = path.resolve(__dirname, '../each');
+
+expect.addSnapshotSerializer({
+  print: value => value,
+  test: received => typeof received === 'string',
+});
+
+test('works with passing tests', () => {
+  const result = runJest(eachDir, [
+    'success.test.js',
+    '--runInBand',
+    '--collect-coverage',
+    '--coverageReporters',
+    'text-summary',
+    '--clear-mocks',
+    '--useStderr',
+  ]);
+  if (result.status !== 0) {
+    console.error(result.stderr);
+  }
+  expect(result.status).toBe(0);
+});
+
+test('throws error for unknown dashed & camelcase args', () => {
+  const result = runJest(consoleDir, [
+    'success.test.js',
+    '--runInBand',
+    '--collect-coverage',
+    '--coverageReporters',
+    'text-summary',
+    '--clear-mocks',
+    '--doesNotExist',
+    '--also-does-not-exist',
+    '--useStderr',
+  ]);
+  expect(result.stderr).toMatchInlineSnapshot(`
+● Unrecognized CLI Parameters:
+
+  Following options were not recognized:
+  ["doesNotExist", "also-does-not-exist"]
+
+  CLI Options Documentation:
+  https://jestjs.io/docs/en/cli.html
+
+
+`);
+  expect(result.status).toBe(1);
+});

packages/jest-cli/src/__tests__/cli/args.test.js

@@ -10,6 +10,7 @@
 
 import type {Argv} from 'types/Argv';
 import {check} from '../../cli/args';
+import {buildArgv} from '../../cli';
 
 describe('check', () => {
   it('returns true if the arguments are valid', () => {
@@ -59,3 +60,15 @@ describe('check', () => {
     );
   });
 });
+
+describe('buildArgv', () => {
+  it('should return only camelcased args ', () => {
+    const mockProcessArgv = jest
+      .spyOn(process.argv, 'slice')
+      .mockImplementation(() => ['--clear-mocks']);
+    const actual = buildArgv(null);
+    expect(actual).not.toHaveProperty('clear-mocks');
+    expect(actual).toHaveProperty('clearMocks', true);
+    mockProcessArgv.mockRestore();
+  });
+});

packages/jest-cli/src/cli/index.js

@@ -35,6 +35,7 @@ import logDebugMessages from '../lib/log_debug_messages';
 
 export async function run(maybeArgv?: Argv, project?: Path) {
   try {
+    // $FlowFixMe:`allow reduced return
     const argv: Argv = buildArgv(maybeArgv, project);
 
     if (argv.init) {
@@ -174,8 +175,9 @@ const readResultsAndExit = (
   }
 };
 
-const buildArgv = (maybeArgv: ?Argv, project: ?Path) => {
-  const argv: Argv = yargs(maybeArgv || process.argv.slice(2))
+export const buildArgv = (maybeArgv: ?Argv, project: ?Path) => {
+  const rawArgv: Argv | string[] = maybeArgv || process.argv.slice(2);
+  const argv: Argv = yargs(rawArgv)
     .usage(args.usage)
     .alias('help', 'h')
     .options(args.options)
@@ -185,9 +187,20 @@ const buildArgv = (maybeArgv: ?Argv, project: ?Path) => {
   validateCLIOptions(
     argv,
     Object.assign({}, args.options, {deprecationEntries}),
+    // strip leading dashes
+    Array.isArray(rawArgv)
+      ? rawArgv.map(rawArgv => rawArgv.replace(/^--?/, ''))
+      : Object.keys(rawArgv),
   );
 
-  return argv;
+  // strip dashed args
+  return Object.keys(argv).reduce((result, key) => {
+    if (!key.includes('-')) {
+      // $FlowFixMe:`allow reduced return
+      result[key] = argv[key];
+    }
+    return result;
+  }, {});
 };
 
 const getProjectListFromCLIArgs = (argv, project: ?Path) => {

packages/jest-validate/package.json

@@ -8,6 +8,7 @@
   "license": "MIT",
   "main": "build/index.js",
   "dependencies": {
+    "camelcase": "^5.0.0",
     "chalk": "^2.0.1",
     "jest-get-type": "^22.1.0",
     "leven": "^2.1.0",

packages/jest-validate/src/validateCLIOptions.js

@@ -10,6 +10,7 @@
 import type {Argv} from 'types/Argv';
 
 import chalk from 'chalk';
+import camelcase from 'camelcase';
 import {createDidYouMeanMessage, format, ValidationError} from './utils';
 import {deprecationWarning} from './deprecated';
 import defaultConfig from './defaultConfig';
@@ -65,15 +66,22 @@ const logDeprecatedOptions = (
   });
 };
 
-export default function validateCLIOptions(argv: Argv, options: Object) {
+export default function validateCLIOptions(
+  argv: Argv,
+  options: Object,
+  rawArgv: string[] = [],
+) {
   const yargsSpecialOptions = ['$0', '_', 'help', 'h'];
   const deprecationEntries = options.deprecationEntries || {};
   const allowedOptions = Object.keys(options).reduce(
     (acc, option) => acc.add(option).add(options[option].alias || option),
     new Set(yargsSpecialOptions),
   );
   const unrecognizedOptions = Object.keys(argv).filter(
-    arg => !allowedOptions.has(arg),
+    arg =>
+      !allowedOptions.has(camelcase(arg)) &&
+      (!rawArgv.length || rawArgv.includes(arg)),
+    [],
   );
 
   if (unrecognizedOptions.length) {

yarn.lock

@@ -3437,6 +3437,11 @@ camelcase@^4.1.0:
   resolved "https://registry.yarnpkg.com/camelcase/-/camelcase-4.1.0.tgz#d545635be1e33c542649c69173e5de6acfae34dd"
   integrity sha1-1UVjW+HjPFQmScaRc+Xeas+uNN0=
 
+camelcase@^5.0.0:
+  version "5.0.0"
+  resolved "https://registry.yarnpkg.com/camelcase/-/camelcase-5.0.0.tgz#03295527d58bd3cd4aa75363f35b2e8d97be2f42"
+  integrity sha512-faqwZqnWxbxn+F1d399ygeamQNy3lPp/H9H6rNrqYh4FSVCtcY+3cub1MxA8o9mDd55mM8Aghuu/kuyYA6VTsA==
+
 caniuse-api@^1.5.2:
   version "1.6.1"
   resolved "https://registry.yarnpkg.com/caniuse-api/-/caniuse-api-1.6.1.tgz#b534e7c734c4f81ec5fbe8aca2ad24354b962c6c"