ESLint config for 5Minds TypeScript projects

• install with

  npm install --save-dev eslint-config-5minds-typescript
  

• install the necessary plugins and parsers with

  npm install --save-dev \
    @typescript-eslint/parser \
    @typescript-eslint/eslint-plugin \
    eslint-plugin-6river \
    eslint-plugin-import \
    eslint-plugin-no-null
  

• create a .eslintrc.json file with

  {
    "extends": "5minds-typescript",
    "parserOptions": {
      "project": "./tsconfig.json"
    }
  }
  

• create a .eslintignore file (like a .gitignore file) with all the folders you dont want linted (e.g. like node_modules and dist)
• If you're using the VSCode eslint extension, add this to your config to make it lint typescript files (you can set autofix to false if you want):

  "eslint.validate": [
    {
      "language": "typescript",
      "autoFix": true
    }
  ]
  

• consider adding a lint-script to your package.json:

  scripts: {
    "lint": "eslint --fix ./**/*.ts"
  }
  

Faster linting

Some special rules require parserServices to be generated. In the default setup, this is done by providing the parserOptions.project value. At the moment, this must be done for the following rules:

• @typescript-eslint/no-for-in-array
• @typescript-eslint/no-unnecessary-qualifier
• @typescript-eslint/no-unnecessary-type-assertion
• @typescript-eslint/restrict-plus-operands
• @typescript-eslint/prefer-includes
• @typescript-eslint/prefer-string-starts-ends-with
• @typescript-eslint/unbound-method

It is nice to be able to use these rules, but they come with a caveat: Providing the parserServices is very slow. Linting a big project took 5 sec. (7 sec. cpu time) without parserServices, and 150 sec. (250 sec. cpu time) with parserServices. (see https://github.com/typescript-eslint/typescript-eslint/issues/243 and https://github.com/typescript-eslint/typescript-eslint/issues/389)

Because of this, this package exposes an additional ruleset, that is identical to the default ruleset, but with the rules that require parserServices disabled. To use this ruleset edit your .eslintrc.json so it looks like this (no parserOptions required!):

{
  "extends": "5minds-typescript/fast"
}