Set ESLint rules as errors while preventing hooks/CI from failing

.eslines.json

@@ -0,0 +1,8 @@
+{
+    "rulesNotToDowngrade": ["no-unused-vars"],
+    "remote": "origin/master",
+    "processors": {
+	    "default": "lines-modified",
+	    "master": "parsing-errors"
+    }
+}

.eslintrc.js

@@ -10,73 +10,8 @@ module.exports = {
 	globals: {
 		asyncRequire: true
 	},
-	// Ideally, we should not have a `rules` block here at all, save for some
-	// Calypso-specific rules (no-unused-expressions, camelcase). The remainder
-	// are rules we cannot yet flag as errors, and should be removed over time
-	// as outstanding issues are resolved.
 	rules: {
-		'array-bracket-spacing': [ 1, 'always' ],
-		'brace-style': [ 1, '1tbs' ],
-		// REST API objects include underscores
-		camelcase: 0,
-		'comma-spacing': 1,
-		curly: 1,
-		'computed-property-spacing': [ 1, 'always' ],
-		'func-call-spacing': 1,
-		indent: [ 1, 'tab', { SwitchCase: 1 } ],
-		'jsx-quotes': [ 1, 'prefer-double' ],
-		'key-spacing': 1,
-		'keyword-spacing': 1,
-		'max-len': [ 1, { code: 140 } ],
-		'new-cap': [ 1, { capIsNew: false, newIsCap: true } ],
-		'no-else-return': 1,
-		'no-extra-semi': 1,
-		'no-multiple-empty-lines': [ 1, { max: 1 } ],
-		'no-multi-spaces': 1,
-		'no-restricted-imports': [ 1, 'lib/sites-list', 'lib/mixins/data-observe' ],
-		'no-restricted-modules': [ 1, 'lib/sites-list', 'lib/mixins/data-observe' ],
-		'no-shadow': 1,
-		'no-spaced-func': 1,
-		'no-trailing-spaces': 1,
-		// Allows Chai `expect` expressions
-		'no-unused-expressions': 0,
-		'no-var': 1,
-		'object-curly-spacing': [ 1, 'always' ],
-		'operator-linebreak': [ 1, 'after', { overrides: {
-			'?': 'before',
-			':': 'before'
-		} } ],
-		'padded-blocks': [ 1, 'never' ],
-		'prefer-const': 1,
-		'quote-props': [ 1, 'as-needed', { keywords: true } ],
-		quotes: [ 1, 'single', 'avoid-escape' ],
-		'react/jsx-curly-spacing': [ 1, 'always' ],
-		'react/jsx-no-bind': 1,
-		'react/jsx-space-before-closing': 1,
-		'react/no-did-mount-set-state': 1,
-		'react/no-did-update-set-state': 1,
-		'react/no-is-mounted': 1,
-		'react/prefer-es6-class': 1,
-		semi: 1,
-		'semi-spacing': 1,
-		'space-before-blocks': [ 1, 'always' ],
-		'space-before-function-paren': [ 1, 'never' ],
-		'space-in-parens': [ 1, 'always' ],
-		'space-infix-ops': [ 1, { int32Hint: false } ],
-		'space-unary-ops': [ 1, {
-			overrides: {
-				'!': true
-			}
-		} ],
-		'template-curly-spacing': [ 1, 'always' ],
-		'valid-jsdoc': [ 1, { requireReturn: false } ],
-		'wpcalypso/i18n-ellipsis': 1,
-		'wpcalypso/i18n-no-collapsible-whitespace': 1,
-		'wpcalypso/i18n-no-this-translate': 1,
-		'wpcalypso/i18n-no-variables': 1,
-		'wpcalypso/i18n-mismatched-placeholders': 1,
-		'wpcalypso/import-docblock': 1,
-		'wpcalypso/jsx-gridicon-size': 1,
-		'wpcalypso/jsx-classname-namespace': 1,
+		camelcase: 0, // REST API objects include underscores
+		'no-unused-expressions': 0, // Allows Chai `expect` expressions
 	}
 };

bin/pre-commit

@@ -1,7 +1,5 @@
 #!/bin/sh
 
-PATH="$PATH:/usr/local/bin"
-
 printf "\nBy contributing to this project, you license the materials you contribute under the GNU General Public License v2 (or later). All materials must have GPLv2 compatible licenses — see .github/CONTRIBUTING.md for details.\n\n"
 
 # Make quick pass over config files on every change
@@ -16,21 +14,13 @@ pass=true
 
 printf "\nValidating .jsx and .js:\n"
 
-for file in ${files}; do
-    ./node_modules/.bin/eslint --cache ${file}
-    if [ $? -ne 0 ]; then
-        printf "\033[31meslint Failed: %s\033[0m\n" "${file}"
-        pass=false
-    else
-        printf "\033[32meslint Passed: %s\033[0m\n" "${file}"
-    fi
-done
-
-printf "\neslint validation complete\n"
-
-if ! $pass; then
-    printf "\n\033[41mCOMMIT FAILED:\033[0m Your commit contains files that should pass validation tests but do not. Please fix the errors and try again.\n\n"
-    exit 1
-else
-    printf "\n\033[42mCOMMIT SUCCEEDED\033[0m\n\n"
+./bin/run-lint $(git diff --cached --name-only client/ server/ test/ | grep ".jsx*$") -- --diff=index
+linter_exit_code=$?
+if [ ! 0 = "$linter_exit_code" ]
+then
+	printf "\n"
+	printf "\033[41mCOMMIT ABORTED:\033[0m the linter reported some problems. If you are aware of them and it is OK, repeat the commit command with --no-verify to avoid this check. You may also want to execute the linter after the errors have been solved: ./bin/run-lint \$(git diff --cached --name-only client/ server/ test/) -- --diff=index"
+	printf "\n"
 fi
+
+exit $linter_exit_code

bin/run-lint

@@ -1,21 +1,59 @@
 #!/usr/bin/env node
-const child_process = require( 'child_process' );
+
 const path = require( 'path' );
-var args = [ '--cache', '--quiet', '--ext=.js',  '--ext=.jsx' ];
-if ( process.argv.length > 2 ) {
-	args = args.concat( process.argv.slice( 2 ) );
+const child_process = require( 'child_process' );
+
+var argsESLint = [ '--cache', '--quiet', '--ext=.js,.jsx', '--format=json' ];
+var argsESLines = [ ];
+
+const markerIndex = process.argv.indexOf('--');
+if ( ( process.argv.length > 2 ) && ( markerIndex > 2 )) {
+	// use -- as a marker for end of options,
+	// so any value that follows the marker is considered an option for ESLines.
+	if ( markerIndex > -1 ) {
+		argsESLint = argsESLint.concat( process.argv.slice( 2, markerIndex ) );
+		argsESLines = argsESLines.concat( process.argv.slice( markerIndex + 1 ) );
+	} else {
+		argsESLint = argsESLint.concat( process.argv.slice( 2 ) );
+	}
 } else {
-	args = args.concat( [ '.' ] );
+	process.stdout.write( 'No files to lint\n' );
+	process.exit( 0 );
 }
 
-const results = child_process.spawnSync( path.join( '.', 'node_modules', '.bin', 'eslint' ), args );
+const eslint = child_process.spawn( path.join( '.', 'node_modules', '.bin', 'eslint' ), argsESLint );
+const eslines = child_process.spawn( path.join( '.', 'node_modules', '.bin', 'eslines' ), argsESLines );
 
-if ( results.stdout ) {
-	process.stdout.write( results.stdout );
-}
-if ( results.stderr ) {
-	process.stderr.write( results.stderr );
-}
-process.on( 'exit', function() {
-	process.exit( results.status );
-} );
+eslint.stdout.on( 'data', ( data ) => {
+	eslines.stdin.write( data );
+});
+
+var eslintStdErr = 0;
+eslint.stderr.on( 'data', ( data ) => {
+	eslintStdErr = 1;
+	process.stderr.write( data );
+});
+
+eslint.on('close', ( code ) => {
+	eslines.stdin.end();
+});
+
+eslines.stdout.on( 'data', ( data ) => {
+	process.stdout.write( data );
+});
+
+eslines.stderr.on( 'data', ( data ) => {
+	process.stderr.write( data );
+});
+
+eslines.on( 'close', ( code ) => {
+	// since the goal of eslines is to downgrade errors
+	// on non-modified lines, we can't count on eslint's
+	// exit code, but we assume that if eslint output
+	// something on its stderr, this means it encountered
+	// some other error
+	if ( eslintStdErr === 1 ) {
+		process.exit( 1 );
+	}
+	process.exit( code );
+});

package.json

@@ -151,7 +151,7 @@
     "test-client:watch": "nodemon -e js,jsx --exec npm run test-client",
     "test-server:watch": "nodemon -e js,jsx --exec npm run test-server",
     "test-test:watch": "nodemon -e js,jsx --exec npm run test-test",
-    "lint": "bin/run-lint",
+    "lint": "bin/run-lint .",
     "css-lint": "stylelint 'client/**/*.scss' --syntax scss"
   },
   "devDependencies": {
@@ -167,6 +167,7 @@
     "esformatter-quotes": "1.0.3",
     "esformatter-semicolons": "1.1.1",
     "esformatter-special-bangs": "1.0.1",
+    "eslines": "0.0.10",
     "eslint": "3.8.1",
     "eslint-config-wpcalypso": "0.6.0",
     "eslint-plugin-react": "6.4.1",