Add TypeScript support

* Adds support for linting TypeScript files
* Re-implements lintText(), lintTextSync() and lintFiles() methods
* Inline the fancy result output logic and update relevant tests

.typescript.eslintrc.js

@@ -0,0 +1,24 @@
+module.exports = {
+  plugins: ['typescript'],
+  rules: {
+    'no-undef': 'off',
+    'no-use-before-define': 'off',
+    'import/imports-first': 'off',
+    'import/first': 'off',
+    'typescript/adjacent-overload-signatures': 'error',
+    'typescript/class-name-casing': 'error',
+    'typescript/explicit-member-accessibility': 'error',
+    'typescript/interface-name-prefix': 'error',
+    'typescript/member-delimiter-style': ['error', {delimiter: 'none', requireLast: true, ignoreSingleLine: true}],
+    'typescript/member-ordering': 'error',
+    'typescript/no-angle-bracket-type-assertion': 'error',
+    'typescript/no-empty-interface': 'error',
+    'typescript/no-namespace': ['error', {allowDefinitionFiles: true}],
+    'typescript/no-parameter-properties': 'error',
+    'typescript/no-triple-slash-reference': 'error',
+    'typescript/no-unused-vars': 'error',
+    'typescript/no-use-before-define': ['error', {functions: false, classes: false, variables: false, typedefs: false}],
+    'typescript/prefer-namespace-keyword': 'error',
+    'typescript/type-annotation-spacing': 'error'
+  }
+}

README.md

@@ -16,8 +16,10 @@ issues](https://github.com/nodesecurity/eslint-plugin-security)
 * Rules for [JSX / React](https://github.com/yannickcr/eslint-plugin-react)
 * Various [awesome](https://github.com/sindresorhus/eslint-plugin-unicorn)
 ESLint rules
+* [TypeScript](http://typescriptlang.org/) support!
 
-See [`.eslintrc.js`](.eslintrc.js) for details.
+See [`.eslintrc.js`](.eslintrc.js) and
+[`.typescript.eslintrc.js`](.typescript.eslintrc.js) for details.
 
 It's what [I](https://novemberborn.net/) use.
 

cli.js

@@ -1,7 +1,3 @@
 #!/usr/bin/env node
-
 'use strict'
-
-require('./lib/patch-file-result-output')(
-  require('standard-engine'), console
-).cli(require('./options'))
+require('./lib/patched-standard-engine').cli(require('./options'))

index.js

@@ -1,3 +1,3 @@
 'use strict'
-
-module.exports = require('standard-engine').linter(require('./options'))
+const Linter = require('./lib/Linter')
+module.exports = new Linter(require('./options'))

lib/Linter.js

@@ -0,0 +1,105 @@
+'use strict'
+
+const deglob = require('deglob')
+const formatter = require('eslint-formatter-pretty')
+const hasFlag = require('has-flag')
+const engine = require('standard-engine')
+
+const DEFAULT_PATTERNS = [
+  '**/*.js',
+  '**/*.jsx',
+  '**/*.d.ts',
+  '**/*.ts',
+  '**/*.tsx'
+]
+
+class Linter extends engine.linter {
+  parseTypescriptOpts (opts, usePackageJson) {
+    return this.parseOpts(Object.assign({}, opts, {parser: 'typescript-eslint-parser'}), usePackageJson)
+  }
+
+  lintTextSync (text, opts) {
+    if (opts.filename && opts.filename.endsWith('.ts')) {
+      opts = this.parseTypescriptOpts(opts, false)
+    } else {
+      opts = this.parseOpts(opts, false)
+    }
+    return new this.eslint.CLIEngine(opts.eslintConfig).executeOnText(text, opts.filename)
+  }
+
+  lintText (text, opts, cb) {
+    try {
+      const report = this.lintTextSync(text, opts)
+      process.nextTick(cb, null, report)
+    } catch (err) {
+      process.nextTick(cb, err)
+    }
+  }
+
+  lintFiles (patterns, opts, cb) {
+    if (typeof opts === 'function') return this.lintFiles(patterns, null, opts)
+
+    const regularOpts = this.parseOpts(opts, true)
+
+    if (typeof patterns === 'string') patterns = [patterns]
+    if (patterns.length === 0) patterns = DEFAULT_PATTERNS
+
+    deglob(patterns, {
+      ignore: regularOpts.ignore,
+      cwd: regularOpts.cwd,
+      useGitIgnore: true,
+      usePackageJson: false
+    }, (globErr, allFiles) => {
+      if (globErr) return cb(globErr)
+
+      const files = allFiles.filter(file => !file.endsWith('.ts'))
+      const tsFiles = allFiles.filter(file => file.endsWith('.ts'))
+
+      let report
+      try {
+        report = new this.eslint.CLIEngine(regularOpts.eslintConfig).executeOnFiles(files)
+      } catch (err) {
+        return cb(err)
+      }
+
+      let tsReport
+      if (tsFiles.length > 0) {
+        try {
+          const tsOpts = this.parseTypescriptOpts(opts, true)
+          tsReport = new this.eslint.CLIEngine(tsOpts.eslintConfig).executeOnFiles(tsFiles)
+        } catch (err) {
+          return cb(err)
+        }
+      }
+
+      const combined = tsReport
+        ? {
+          results: report.results.concat(tsReport.results),
+          errorCount: report.errorCount + tsReport.errorCount,
+          warningCount: report.warningCount + tsReport.warningCount,
+          fixableErrorCount: report.fixableErrorCount + tsReport.fixableErrorCount,
+          fixableWarningCount: report.fixableWarningCount + tsReport.fixableWarningCount
+        }
+        : report
+
+      if (regularOpts.fix) {
+        this.eslint.CLIEngine.outputFixes(combined)
+      }
+
+      Object.defineProperty(combined.results, 'forEach', {
+        enumerable: false,
+        value () {
+          const output = formatter(this.slice())
+          if (hasFlag('stdin') && regularOpts.fix) {
+            console.error(output)
+          } else {
+            console.log(output)
+          }
+        }
+      })
+
+      cb(null, combined)
+    })
+  }
+}
+module.exports = Linter

lib/patched-standard-engine.js

@@ -0,0 +1,7 @@
+'use strict'
+
+const engine = require('standard-engine')
+const Linter = require('./Linter')
+
+engine.linter = opts => new Linter(opts)
+module.exports = engine

lib/settings.js

@@ -5,11 +5,14 @@ const arrify = require('arrify')
 const resolveFrom = require('resolve-from')
 const baseRules = require('../.eslintrc').rules
 const patchImportRule = require('./patch-import-rule')
+const mergeTypescriptConfig = require('./typescript')
 
 const ALLOW_DEV_DEPENDENCIES = [
-  'scripts/**/*.js',
+  'scripts/**/{*.js,*.ts}',
   'test.js',
-  'test/**/*.js'
+  'test.ts',
+  'test/**/{*.js,*.ts}',
+  'typings/**/*.d.ts'
 ]
 
 function applySettings (eslintConfig, settings, rootDir) {
@@ -64,6 +67,10 @@ function applySettings (eslintConfig, settings, rootDir) {
       }
     }
   }
+
+  if (eslintConfig.parser === 'typescript-eslint-parser') {
+    mergeTypescriptConfig(eslintConfig)
+  }
 }
 
 module.exports = applySettings

lib/typescript.js

@@ -0,0 +1,19 @@
+'use strict'
+
+const config = require('../.typescript.eslintrc')
+
+function mergeTypescriptConfig (eslintConfig) {
+  for (const plugin of config.plugins) {
+    eslintConfig.plugins.push(plugin)
+  }
+  Object.assign(eslintConfig.rules, config.rules)
+
+  if (!eslintConfig.baseConfig) eslintConfig.baseConfig = {}
+  const baseConfig = eslintConfig.baseConfig
+  if (!baseConfig.settings) baseConfig.settings = {}
+  const settings = baseConfig.settings
+  if (!settings['import/resolver']) settings['import/resolver'] = {}
+  const resolver = settings['import/resolver']
+  resolver['eslint-import-resolver-typescript'] = true
+}
+module.exports = mergeTypescriptConfig

package.json

@@ -8,6 +8,7 @@
   },
   "files": [
     ".eslintrc.js",
+    ".typescript.eslintrc.js",
     "cli.js",
     "index.js",
     "options.js",
@@ -32,9 +33,11 @@
   "dependencies": {
     "arrify": "^1.0.1",
     "babel-eslint": "8.0.1",
+    "deglob": "^2.1.0",
     "eslint": "4.10.0",
     "eslint-config-standard": "10.2.1",
     "eslint-formatter-pretty": "^1.1.0",
+    "eslint-import-resolver-typescript": "1.0.2",
     "eslint-plugin-ava": "4.2.2",
     "eslint-plugin-import": "2.8.0",
     "eslint-plugin-node": "5.2.1",
@@ -43,16 +46,19 @@
     "eslint-plugin-react": "7.4.0",
     "eslint-plugin-security": "1.4.0",
     "eslint-plugin-standard": "3.0.1",
+    "eslint-plugin-typescript": "0.8.0",
     "eslint-plugin-unicorn": "github:sindresorhus/eslint-plugin-unicorn#cba8dd9f31f2ff5646376b137a85f95ab2567e98",
     "has-flag": "^2.0.0",
     "resolve-from": "^4.0.0",
-    "standard-engine": "7.1.0"
+    "standard-engine": "7.1.0",
+    "typescript-eslint-parser": "8.0.1"
   },
   "devDependencies": {
     "ava": "^0.23.0",
     "codecov": "^3.0.0",
     "get-stream": "^3.0.0",
-    "nyc": "^11.2.1"
+    "nyc": "^11.2.1",
+    "typescript": "^2.5.3"
   },
   "engines": {
     "node": ">=4"