Remove the esnext option

Author: sindresorhus

Diff for: cli-main.js

@@ -27,7 +27,6 @@ const cli = meow(`
 	  --open            Open files with issues in your editor
 	  --quiet           Show only errors and no warnings
 	  --extension       Additional extension to lint [Can be set multiple times]
-	  --no-esnext       Don't enforce ES2015+ rules
 	  --cwd=<dir>       Working directory for files
 	  --stdin           Validate/fix code from stdin
 	  --stdin-filename  Specify a filename for the --stdin option
@@ -97,9 +96,6 @@ const cli = meow(`
 			type: 'string',
 			isMultiple: true
 		},
-		esnext: {
-			type: 'boolean'
-		},
 		cwd: {
 			type: 'string'
 		},

Diff for: lib/options-manager.js

@@ -162,9 +162,11 @@ const mergeWithFileConfigs = async (files, options, configFiles) => {
 		([tsConfigPath, groups]) => {
 			const files = [].concat(...groups.map(group => group.files));
 			const cachePath = getTsConfigCachePath(files, tsConfigPath);
-			groups.forEach(group => {
+
+			for (const group of groups) {
 				group.options.tsConfigPath = cachePath;
-			});
+			}
+
 			return outputJson(cachePath, makeTSConfig(tsConfigs[tsConfigPath], tsConfigPath, files));
 		}
 	));
@@ -180,11 +182,11 @@ Hashing based on https://github.com/eslint/eslint/blob/cf38d0d939b62f3670cdd59f0
 */
 const getTsConfigCachePath = (files, tsConfigPath) => path.join(
 	cacheLocation,
-	`tsconfig.${murmur(`${pkg.version}_${nodeVersion}_${stringify({files: files.sort(), tsConfigPath: tsConfigPath})}`).result().toString(36)}.json`
+	`tsconfig.${murmur(`${pkg.version}_${nodeVersion}_${stringify({files: files.sort(), tsConfigPath})}`).result().toString(36)}.json`
 );
 
 const makeTSConfig = (tsConfig, tsConfigPath, files) => {
-	const config = {files: files.filter(isTypescript)};
+	const config = {files: files.filter(file => isTypescript(file))};
 
 	if (tsConfig) {
 		config.extends = tsConfigPath;
@@ -308,13 +310,6 @@ const buildXOConfig = options => config => {
 		}];
 	}
 
-	if (options.esnext !== false) {
-		config.baseConfig.extends = [
-			'xo/esnext',
-			path.join(__dirname, '../config/plugins.js')
-		];
-	}
-
 	if (options.ts) {
 		config.rules['unicorn/import-style'] = 'off';
 		config.rules['node/file-extension-in-import'] = 'off';
@@ -464,7 +459,7 @@ const applyOverrides = (file, options) => {
 		const {overrides} = options;
 		delete options.overrides;
 
-		let {applicable, hash} = findApplicableOverrides(path.relative(options.cwd, file), overrides);
+		const {applicable, hash} = findApplicableOverrides(path.relative(options.cwd, file), overrides);
 
 		options = mergeWith(...[getEmptyOptions(), options].concat(applicable.map(override => normalizeOptions(override)), mergeFn));
 		delete options.files;

Diff for: package.json

@@ -58,7 +58,7 @@
 		"debug": "^4.3.1",
 		"eslint": "^7.20.0",
 		"eslint-config-prettier": "^7.2.0",
-		"eslint-config-xo": "^0.35.0",
+		"eslint-config-xo": "^0.36.0",
 		"eslint-config-xo-typescript": "^0.38.0",
 		"eslint-formatter-pretty": "^4.0.0",
 		"eslint-import-resolver-webpack": "^0.13.0",

Diff for: readme.md

@@ -68,7 +68,6 @@ $ xo --help
     --open            Open files with issues in your editor
     --quiet           Show only errors and no warnings
     --extension       Additional extension to lint [Can be set multiple times]
-    --no-esnext       Don't enforce ES2015+ rules
     --cwd=<dir>       Working directory for files
     --stdin           Validate/fix code from stdin
     --stdin-filename  Specify a filename for the --stdin option
@@ -267,15 +266,6 @@ Type: `string`
 
 [ESLint processor.](https://eslint.org/docs/user-guide/configuring#specifying-processor)
 
-### esnext
-
-Type: `boolean`\
-Default: `true`
-
-Enforce ES2015+ rules. Disabling this will make it not *enforce* ES2015+ syntax and conventions.
-
-*ES2015+ is parsed even without this option. You can already use ES2017 features like [`async`/`await`](https://github.com/lukehoban/ecmascript-asyncawait).
-
 ### webpack
 
 Type: `boolean | object`
@@ -317,12 +307,11 @@ XO makes it easy to override configs for specific files. The `overrides` propert
 		"overrides": [
 			{
 				"files": "test/*.js",
-				"esnext": false,
 				"space": 3
 			},
 			{
 				 "files": "test/foo.js",
-				 "esnext": true
+				 "semicolon": true
 			}
 		]
 	}
@@ -331,11 +320,10 @@ XO makes it easy to override configs for specific files. The `overrides` propert
 
 - The base configuration is simply `space: 2`, `semicolon: false`. These settings are used for every file unless otherwise noted below.
 
-- For every file in `test/*.js`, the base config is used, but `space` is overridden with `3`, and the `esnext` option is set to `false`. The resulting config is:
+- For every file in `test/*.js`, the base config is used, but `space` is overridden with `3`. The resulting config is:
 
 ```json
 {
-	"esnext": false,
 	"semicolon": false,
 	"space": 3
 }
@@ -345,8 +333,7 @@ XO makes it easy to override configs for specific files. The `overrides` propert
 
 ```json
 {
-	"esnext": true,
-	"semicolon": false,
+	"semicolon": true,
 	"space": 3
 }
 ```

Diff for: test/fixtures/config-files/xo-config/.xo-config

@@ -1,3 +1,3 @@
 {
-    "esnext": true
+    "space": true
 }

Diff for: test/fixtures/config-files/xo-config/file.js

@@ -1,2 +1,5 @@
-var obj = { a: 1 };
-console.log(obj.a);
+const object = {
+	a: 1
+};
+
+console.log(object.a);

Diff for: test/fixtures/config-files/xo-config_js/.xo-config.js

@@ -1,3 +1,3 @@
 module.exports = {
-    esnext: true
-}
+	space: true
+};

Diff for: test/fixtures/config-files/xo-config_js/file.js

@@ -1,2 +1,5 @@
-var obj = { a: 1 };
-console.log(obj.a);
+const object = {
+	a: 1
+};
+
+console.log(object.a);

Diff for: test/fixtures/config-files/xo-config_json/.xo-config.json

@@ -1,3 +1,3 @@
 {
-    "esnext": true
+	"space": true
 }

Diff for: test/fixtures/config-files/xo-config_json/file.js

@@ -1,2 +1,5 @@
-var obj = { a: 1 };
-console.log(obj.a);
+const object = {
+	a: 1
+};
+
+console.log(object.a);

Diff for: test/fixtures/config-files/xo_config_js/file.js

@@ -1,2 +1,5 @@
-var obj = { a: 1 };
-console.log(obj.a);
+const object = {
+	a: 1
+};
+
+console.log(object.a);

Diff for: test/fixtures/config-files/xo_config_js/xo.config.js

@@ -1,3 +1,3 @@
 module.exports = {
-	esnext: true
-}
+	space: true
+};

Diff for: test/fixtures/nested/child/package.json

@@ -1,5 +1,5 @@
 {
 	"xo": {
-		"esnext": false
+		"space": true
 	}
 }

Diff for: test/fixtures/nested/file.js

@@ -1,2 +1,2 @@
-var obj = { a: 1 };
-console.log(obj.a);
+const object = {a: 1};
+console.log(object.a);

Diff for: test/fixtures/nested/package.json

@@ -1,5 +1,5 @@
 {
 	"xo": {
-		"esnext": true
+		"space": true
 	}
 }

Diff for: test/fixtures/overrides/package.json

@@ -5,7 +5,6 @@
 		"overrides": [
 			{
 				"files": "test/*.js",
-				"esnext": true,
 				"space": 3
 			},
 			{

Diff for: test/lint-files.js

@@ -197,8 +197,8 @@ test('typescript files', async t => {
 });
 
 test('typescript 2 space option', async t => {
-	const {errorCount} = await fn.lintFiles('two-spaces.tsx', {cwd: 'fixtures/typescript', space: 2});
-	t.is(errorCount, 0);
+	const {errorCount, results} = await fn.lintFiles('two-spaces.tsx', {cwd: 'fixtures/typescript', space: 2});
+	t.is(errorCount, 0, JSON.stringify(results[0].messages));
 });
 
 test('typescript 4 space option', async t => {
@@ -270,7 +270,7 @@ async function configType(t, {dir}) {
 		hasRule(
 			results,
 			path.resolve('fixtures', 'config-files', dir, 'file.js'),
-			'no-var'
+			'indent'
 		)
 	);
 }

Diff for: test/lint-text.js

@@ -102,13 +102,6 @@ test('extends support', t => {
 	t.true(hasRule(results, 'react/jsx-no-undef'));
 });
 
-test('extends support with `esnext` option', t => {
-	const {results} = fn.lintText('import path from \'path\';\nlet React;\nReact.render(<App/>);\n', {
-		extends: 'xo-react'
-	});
-	t.true(hasRule(results, 'react/jsx-no-undef'));
-});
-
 test('disable style rules when `prettier` option is enabled', t => {
 	const withoutPrettier = fn.lintText('(a) => {}\n', {filename: 'test.js'}).results;
 	// `arrow-parens` is enabled
@@ -131,11 +124,6 @@ test('extends `react` support with `prettier` option', t => {
 	t.true(hasRule(results, 'prettier/prettier'));
 });
 
-test('always use the latest ECMAScript parser so esnext syntax won\'t throw in normal mode', t => {
-	const {results} = fn.lintText('async function foo() {}\n\nfoo();\n');
-	t.is(results[0].errorCount, 0);
-});
-
 test('regression test for #71', t => {
 	const {results} = fn.lintText('const foo = { key: \'value\' };\nconsole.log(foo);\n', {
 		extends: path.join(__dirname, 'fixtures/extends.js')

Diff for: test/options-manager.js

@@ -49,11 +49,6 @@ test('buildConfig: defaults', t => {
 	t.regex(slash(config.cacheLocation), /[\\/]\.cache\/xo-linter\/xo-cache.json[\\/]?$/u);
 	t.is(config.useEslintrc, false);
 	t.is(config.cache, true);
-	t.is(config.baseConfig.extends[0], 'xo/esnext');
-});
-
-test('buildConfig: esnext', t => {
-	const config = manager.buildConfig({esnext: false});
 	t.is(config.baseConfig.extends[0], 'xo');
 });
 
@@ -171,27 +166,6 @@ test('buildConfig: prettier: true, space: 4', t => {
 	t.is(config.rules['semi-spacing'], undefined);
 });
 
-test('buildConfig: prettier: true, esnext: false', t => {
-	const config = manager.buildConfig({prettier: true, esnext: false}, {});
-
-	// Sets `useTabs` and `tabWidth` options in `prettier/prettier` rule based on the XO `space` options
-	t.deepEqual(config.rules['prettier/prettier'], ['error', {
-		useTabs: true,
-		bracketSpacing: false,
-		jsxBracketSameLine: false,
-		semi: true,
-		singleQuote: true,
-		tabWidth: 2,
-		trailingComma: 'none'
-	}]);
-	// Indent rule is not enabled
-	t.is(config.rules.indent, undefined);
-	// Semi rule is not enabled
-	t.is(config.rules.semi, undefined);
-	// Semi-spacing is not enabled
-	t.is(config.rules['semi-spacing'], undefined);
-});
-
 test('buildConfig: prettier: true, space: true', t => {
 	const config = manager.buildConfig({prettier: true, space: true}, {});