build: replace tslint with eslint (#1382)

fixes #1271

.eslintrc.js

@@ -0,0 +1,69 @@
+module.exports = {
+  // Common settings for JS Files.
+  extends: ["plugin:eslint-comments/recommended", "prettier"],
+  env: {
+    es6: true,
+    commonjs: true,
+    mocha: true,
+    node: true
+  },
+  globals: {
+    expect: true,
+    define: true,
+    window: true
+  },
+  rules: {
+    "eslint-comments/require-description": ["error", { ignore: [] }]
+  },
+  overrides: [
+    {
+      // For pure-java script sub-packages and general scripts (in any package).
+      files: ["*.js"],
+      extends: ["eslint:recommended"],
+      excludedFiles: [
+        "**/vendor/**/*.js",
+        "**/diagrams/**/*.js",
+        "**/benchmark_web/**/*.js"
+      ],
+
+      parserOptions: {
+        // The `ecmaVersion` should align to the supported features of our target runtimes (browsers / nodejs / others)
+        // Consult with: https://kangax.github.io/compat-table/es2016plus/
+        ecmaVersion: 2017
+      }
+    },
+    {
+      // For sub-packages using TypeScript (libraries/VSCode Exts) && TypeScript definitions (d.ts)
+      files: ["*.ts"],
+      plugins: ["@typescript-eslint"],
+      parser: "@typescript-eslint/parser",
+      parserOptions: {
+        // project: ["./tsconfig.base.json", "./tsconfig.json"],
+      },
+      extends: [
+        "plugin:@typescript-eslint/eslint-recommended"
+        // "plugin:@typescript-eslint/recommended-requiring-type-checking",
+      ],
+      rules: {
+        "@typescript-eslint/no-use-before-define": [
+          "error",
+          // These can be safely used before they are defined due to function hoisting in EcmaScript
+          { functions: false, classes: false }
+        ]
+        // TODO: This rule configuration is very useful, attempt to apply it on the existing code base in the future
+        // "@typescript-eslint/ban-ts-comment": [
+        //   "error",
+        //   {
+        //     // We only allow ts-expect-error comments to enforce removal
+        //     // of outdated suppression comments when the underlying issue has been resolved.
+        //     // https://devblogs.microsoft.com/typescript/announcing-typescript-3-9/#what-about-ts-ignore
+        //     "ts-expect-error": "allow-with-description",
+        //     "ts-ignore": true,
+        //     "ts-nocheck": true,
+        //     "ts-check": true,
+        //   },
+        // ],
+      }
+    }
+  ]
+}

examples/grammars/css/css.js

@@ -45,6 +45,7 @@ FRAGMENT("spaces", "[ \\t\\r\\n\\f]+")
 FRAGMENT("ident", "-?{{nmstart}}{{nmchar}}*")
 FRAGMENT("num", "[0-9]+|[0-9]*\\.[0-9]+")
 
+/* eslint-disable no-unused-vars -- tokens are collected in our `createToken` wrapper */
 const Whitespace = createToken({
   name: "Whitespace",
   pattern: MAKE_PATTERN("{{spaces}}"),
@@ -244,6 +245,8 @@ const Ident = createToken({
 
 const Minus = createToken({ name: "Minus", pattern: /-/ })
 
+/* eslint-enable no-unused-vars -- tokens are collected in our `createToken` wrapper */
+
 const CssLexer = new Lexer(cssTokens)
 
 // ----------------- parser -----------------

examples/grammars/ecma5/ecma5_parser.js

@@ -1,6 +1,11 @@
 "use strict"
 
-const { EmbeddedActionsParser, EOF, tokenMatcher } = require("chevrotain")
+const {
+  EmbeddedActionsParser,
+  EOF,
+  tokenMatcher,
+  MismatchedTokenException
+} = require("chevrotain")
 const tokens = require("./ecma5_tokens")
 // for conciseness
 const t = tokens
@@ -689,7 +694,7 @@ class ECMAScript5Parser extends EmbeddedActionsParser {
         // there is no danger of inRule recovery (single token insertion/deletion)
         // happening in this case because that type of recovery can only happen if CONSUME(...) was invoked.
         this.SAVE_ERROR(
-          new chevrotain.MismatchedTokenException(
+          new MismatchedTokenException(
             "Line Terminator not allowed before Expression in Throw Statement"
             // TODO: create line terminator token on the fly?
           )
@@ -865,8 +870,9 @@ class ECMAScript5Parser extends EmbeddedActionsParser {
   // the "IN" is only allowed if x is a left hand side expression
   // https://www.ecma-international.org/ecma-262/5.1/index.html#sec-12.6
   // so this method must verify that the exp parameter fulfills this condition.
+  // eslint-disable-next-line no-unused-vars -- function signature
   canInComeAfterExp(exp) {
-    // TODO: temp implemntatoin, will always allow IN style iteration for now.
+    // TODO: temp implementation, will always allow IN style iteration for now.
     return true
   }
 

examples/grammars/graphql/graphql.js

@@ -13,7 +13,7 @@
  */
 // wrapping in UMD to allow code to work both in node.js
 // and in the browser
-;(function (root, factory) {
+(function (root, factory) {
   if (typeof module === "object" && module.exports) {
     // Node. Does not work with strict CommonJS, but
     // only CommonJS-like environments that support module.exports,
@@ -84,6 +84,8 @@
     return newNotTokenCategory
   }
 
+  /* eslint-disable no-unused-vars -- tokens are collected in our `createToken` wrapper */
+
   // B1 - Ignored-Tokens
   // http://facebook.github.io/graphql/June2018/#sec-Appendix-Grammar-Summary.Ignored-Tokens
   const WhiteSpace = createToken({
@@ -116,6 +118,8 @@
     group: Lexer.SKIPPED
   })
 
+  /* eslint-enable no-unused-vars -- tokens are collected in our `createToken` wrapper */
+
   // B2 - Lexical Tokens
   // http://facebook.github.io/graphql/June2018/#sec-Appendix-Grammar-Summary.Lexical-Tokens
   // Punctuator

examples/grammars/tinyc/tinyc.js

@@ -16,7 +16,7 @@ function createToken(options) {
   return newToken
 }
 
-const WhiteSpace = createToken({
+createToken({
   name: "WhiteSpace",
   pattern: /\s+/,
   group: Lexer.SKIPPED

examples/implementation_languages/ecma6/ecma6_json.js

@@ -47,7 +47,7 @@ const JsonLexer = new Lexer(allTokens)
 
 // ----------------- parser -----------------
 class JsonParserES6 extends CstParser {
-  constructor(input) {
+  constructor() {
     super(allTokens)
 
     // not mandatory, using $ (or any other sign) to reduce verbosity (this. this. this. this. .......)

examples/lexer/custom_errors/custom_errors.js

@@ -10,13 +10,15 @@ const Whitespace = createToken({
 })
 
 // A link to the detailed API for the ILexerErrorMessageProvider can be found here:
-// https://chevrotain.io/docs/features/custom_errors.htmlconst OyVeyErrorMessageProvider = {
+// https://chevrotain.io/docs/features/custom_errors.html
 const OyVeyErrorMessageProvider = {
   buildUnexpectedCharactersMessage(
     fullText,
     startOffset,
     length,
+    // eslint-disable-next-line  no-unused-vars -- template
     line,
+    // eslint-disable-next-line  no-unused-vars -- template
     column
   ) {
     return (

examples/lexer/keywords_vs_identifiers/keywords_vs_identifiers.js

@@ -39,7 +39,7 @@ const Whitespace = createToken({
   group: Lexer.SKIPPED
 })
 
-keywordsVsIdentifiersLexer = new Lexer([
+const keywordsVsIdentifiersLexer = new Lexer([
   Whitespace, // Whitespace is very common in most languages so placing it first generally speeds up the lexing.
 
   While, // the actual keywords (While/For/Do) must appear BEFORE the Identifier Token as they are all a valid prefix of it's PATTERN.

examples/parser/content_assist/content_assist_simple.js

@@ -7,7 +7,6 @@
  * "Public sta" --> ["static"]
  * "call f" --> ["foo"] // assuming foo is in the symbol table.
  */
-const _ = require("lodash")
 const { createToken, Lexer, CstParser } = require("chevrotain")
 
 const A = createToken({ name: "A", pattern: /A/ })

examples/parser/custom_errors/custom_errors.js

@@ -56,7 +56,7 @@ const myErrorProvider = {
 
 // ----------------- parser -----------------
 class CustomErrorsParser extends CstParser {
-  constructor(input) {
+  constructor() {
     super(allTokens, {
       // passing our custom error message provider
       errorMessageProvider: myErrorProvider
@@ -124,6 +124,7 @@ function parseStartingWithRule(ruleName) {
     // setting a new input will RESET the parser instance's state.
     parser.input = lexResult.tokens
     // just invoke which ever rule you want as the start rule. its all just plain javascript...
+    // eslint-disable-next-line  no-unused-vars -- template
     const cst = parser[ruleName]()
 
     // we are only interested in the errors in this scenario.

examples/tutorial/step1_lexing/step1_lexing_spec.js

@@ -1,6 +1,5 @@
 "use strict"
 const expect = require("chai").expect
-const _ = require("lodash")
 const tokenMatcher = require("chevrotain").tokenMatcher
 const lex = require("./step1_lexing").lex
 const tokenVocabulary = require("./step1_lexing").tokenVocabulary

examples/tutorial/step2_parsing/step2_parsing_spec.js

@@ -1,6 +1,5 @@
 "use strict"
 const expect = require("chai").expect
-const _ = require("lodash")
 const parse = require("./step2_parsing").parse
 
 describe("Chevrotain Tutorial", () => {

examples/tutorial/step3_actions/step3_actions_spec.js

@@ -1,6 +1,5 @@
 "use strict"
 const expect = require("chai").expect
-const _ = require("lodash")
 const toAstVisitor = require("./step3a_actions_visitor").toAst
 const toAstEmbedded = require("./step3b_actions_embedded").toAst
 

package.json

@@ -10,11 +10,13 @@
   "scripts": {
     "lerna:version": "yarn && lerna version",
     "lerna:publish": "lerna publish from-git --yes --no-verify-access",
-    "ci": "npm-run-all format:validate build test",
+    "ci": "npm-run-all format:validate lint:validate build test",
     "build": "lerna run build",
     "test": "lerna run test",
     "format:fix": "prettier --ignore-path .gitignore --write \"**/*.@(ts|js|json|md|yml)\"",
-    "format:validate": "prettier --ignore-path .gitignore --check \"**/*.@(ts|js|json|md|yml)\""
+    "format:validate": "prettier --ignore-path .gitignore --check \"**/*.@(ts|js|json|md|yml)\"",
+    "lint:fix": "eslint . --ext=js,ts --fix --max-warnings=0 --ignore-path=.gitignore",
+    "lint:validate": "eslint . --ext=js,ts --max-warnings=0 --ignore-path=.gitignore"
   },
   "prettier": {
     "endOfLine": "lf",
@@ -30,6 +32,9 @@
   "lint-staged": {
     "*.{ts,js,json,md}": [
       "prettier --write"
+    ],
+    "*.{ts,js}": [
+      "eslint --fix --max-warnings=0 --ignore-pattern=!.*"
     ]
   },
   "config": {
@@ -54,6 +59,11 @@
     "shx": "^0.3.2",
     "cz-conventional-changelog": "3.3.0",
     "@commitlint/cli": "12.0.0",
-    "@commitlint/config-conventional": "12.0.0"
+    "@commitlint/config-conventional": "12.0.0",
+    "eslint": "7.18.0",
+    "@typescript-eslint/parser": "4.14.0",
+    "@typescript-eslint/eslint-plugin": "4.15.0",
+    "eslint-config-prettier": "7.2.0",
+    "eslint-plugin-eslint-comments": "3.2.0"
   }
 }

packages/chevrotain/diagrams/src/diagrams_builder.js

@@ -20,7 +20,7 @@
   var Optional = railroad.Optional
   var OneOrMore = railroad.OneOrMore
   var ZeroOrMore = railroad.ZeroOrMore
-  var Terminal = railroad.Terminal
+  // var Terminal = railroad.Terminal
   var NonTerminal = railroad.NonTerminal
 
   /**

packages/chevrotain/package.json

@@ -45,7 +45,7 @@
   "homepage": "https://chevrotain.io/docs/",
   "scripts": {
     "---------- CI FLOWS --------": "",
-    "build": "npm-run-all clean lint compile build:esm dts api-site:build bundle",
+    "build": "npm-run-all clean compile build:esm dts api-site:build bundle",
     "build:esm": "npm-run-all clean:esm compile:esm",
     "test": "npm-run-all test:esm compile:def coverage check-coverage",
     "test:esm": "mocha \"./lib_esm/test/**/*spec.js\" --require esm",
@@ -58,7 +58,6 @@
     "---------- BUILD STEPS --------": "",
     "clean": "shx rm -rf coverage dev lib",
     "clean:esm": "shx rm -rf lib_esm",
-    "lint": "tslint --project tsconfig.json",
     "compile": "tsc && node ./scripts/fix-coverage-report.js",
     "compile:esm": "tsc --project tsconfig.esm.json",
     "compile:watch": "tsc -w",
@@ -99,7 +98,6 @@
     "sinon": "^9.0.0",
     "sinon-chai": "^3.0.0",
     "source-map-support": "0.5.19",
-    "tslint": "^6.0.0",
     "typedoc": "^0.20.28",
     "typescript": "4.2.2",
     "vuepress": "^1.4.1",

packages/chevrotain/scripts/update-api-docs.js

@@ -1,8 +1,7 @@
-const _ = require("lodash")
 const fs = require("fs-extra")
 const path = require("path")
 
-pkgPath = path.join(__dirname, "../package.json")
+const pkgPath = path.join(__dirname, "../package.json")
 const pkg = fs.readJsonSync(pkgPath)
 
 console.log("updating api docs re-direct")
@@ -15,7 +14,7 @@ const newVersionApiDocsDir = path.join(
 )
 
 try {
-  stats = fs.lstatSync(newVersionApiDocsDir)
+  const stats = fs.lstatSync(newVersionApiDocsDir)
 
   if (stats.isDirectory()) {
     console.error("docs directory for " + noDotsVersion + " already exists")

packages/chevrotain/src/generate/generate.ts

@@ -59,7 +59,7 @@ return new ${options.name}(tokenVocabulary, config)
 
 export function genClass(options: { name: string; rules: Rule[] }): string {
   // TODO: how to pass the token vocabulary? Constructor? other?
-  let result = `
+  const result = `
 function ${options.name}(tokenVocabulary, config) {
     // invoke super constructor
     // No support for embedded actions currently, so we can 'hardcode'
@@ -85,7 +85,7 @@ ${options.name}.prototype.constructor = ${options.name}
 }
 
 export function genAllRules(rules: Rule[]): string {
-  let rulesText = map(rules, (currRule) => {
+  const rulesText = map(rules, (currRule) => {
     return genRule(currRule, 1)
   })
 

packages/chevrotain/src/lang/lang_extensions.ts

@@ -15,7 +15,7 @@ const NAME = "name"
 export function functionName(func: TokenType): string {
   // Engines that support Function.prototype.name OR the nth (n>1) time after
   // the name has been computed in the following else block.
-  let existingNameProp = (<any>func).name
+  const existingNameProp = (<any>func).name
   /* istanbul ignore else - too many hacks for IE/old versions of node.js here*/
   if (existingNameProp) {
     return existingNameProp
@@ -28,7 +28,7 @@ export function functionName(func: TokenType): string {
  * @returns {boolean} - has the property been successfully defined
  */
 export function defineNameProp(obj, nameValue): boolean {
-  let namePropDescriptor = Object.getOwnPropertyDescriptor(obj, NAME)
+  const namePropDescriptor = Object.getOwnPropertyDescriptor(obj, NAME)
   /* istanbul ignore else -> will only run in old versions of node.js */
   if (isUndefined(namePropDescriptor) || namePropDescriptor.configurable) {
     Object.defineProperty(obj, NAME, {

packages/chevrotain/src/parse/constants.ts

@@ -1,2 +1,2 @@
 // TODO: can this be removed? where is it used?
-export let IN = "_~IN~_"
+export const IN = "_~IN~_"