Support dashed args

CHANGELOG.md

@@ -38,6 +38,7 @@
 
 ### Fixes
 
+- `[jest-cli]` Support dashed args ([#7497](https://github.com/facebook/jest/pull/7497))
 - `[jest-cli]` [**BREAKING**] Do not use `text-summary` coverage reporter by default if other reporters are configured ([#7058](https://github.com/facebook/jest/pull/7058))
 - `[jest-mock]` [**BREAKING**] Fix bugs with mock/spy result tracking of recursive functions ([#6381](https://github.com/facebook/jest/pull/6381))
 - `[jest-haste-map]` [**BREAKING**] Recover files correctly after haste name collisions are fixed ([#7329](https://github.com/facebook/jest/pull/7329))

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. Which means the following examples will have equal result:
+
+```bash
+jest --collect-coverage
+jest --collectCoverage
+```
+
+They 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/cli/index.js

@@ -175,7 +175,8 @@ const readResultsAndExit = (
 };
 
 const buildArgv = (maybeArgv: ?Argv, project: ?Path) => {
-  const argv: Argv = yargs(maybeArgv || process.argv.slice(2))
+  const rawArgv: Argv | string[] = maybeArgv || process.argv.slice(2);
+  const argv: Argv = yargs(rawArgv)
     .usage(args.usage)
     .alias('help', 'h')
     .options(args.options)
@@ -185,6 +186,9 @@ const buildArgv = (maybeArgv: ?Argv, project: ?Path) => {
   validateCLIOptions(
     argv,
     Object.assign({}, args.options, {deprecationEntries}),
+    Array.isArray(rawArgv)
+      ? rawArgv.map(rawArgv => rawArgv.replace(/^--?/, ''))
+      : Object.keys(rawArgv),
   );
 
   return argv;

packages/jest-validate/src/validateCLIOptions.js

@@ -65,16 +65,27 @@ 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),
-  );
+  const unrecognizedOptions = Object.keys(argv).filter(arg => {
+    const camelCased = arg.replace(/-([^-])/g, (a, b) => b.toUpperCase());
+    if (
+      !allowedOptions.has(camelCased) &&
+      (!rawArgv.length || rawArgv.includes(arg))
+    ) {
+      return true;
+    }
+    return false;
+  }, []);
 
   if (unrecognizedOptions.length) {
     throw createCLIValidationError(unrecognizedOptions, allowedOptions);