.eslintrc

{
  "parser": "@typescript-eslint/parser",
  "env": {
    "node": true
  },
  "parserOptions": {
    "ecmaVersion": 2018,
    "sourceType": "module",
    "project": "./tsconfig.json"
  },
  "plugins": ["@typescript-eslint"],
  "extends": ["eslint:recommended", "plugin:@typescript-eslint/recommended"],
  "rules": {
    "@typescript-eslint/indent": ["error", 2],
    // Style
    "quotes": ["error", "single", { "avoidEscape": true }],
    "comma-dangle": ["error", "always-multiline"], // ensures clean diffs, see https://medium.com/@nikgraf/why-you-should-enforce-dangling-commas-for-multiline-statements-d034c98e36f8
    "comma-spacing": ["error", { "before": false, "after": true }], // space after, no space before
    "no-multi-spaces": ["error", { "ignoreEOLComments": false }], // no multi spaces
    "array-bracket-spacing": ["error", "never"], // [1, 2, 3]
    "array-bracket-newline": ["error", "consistent"], // enforce consistent line breaks between brackets
    "object-curly-spacing": ["error", "always"], // { key: 'value' }
    "object-curly-newline": [
      "error",
      { "multiline": true, "consistent": true }
    ], // enforce consistent line breaks between braces
    "object-property-newline": [
      "error",
      { "allowAllPropertiesOnSameLine": true }
    ], // enforce "same line" or "multiple line" on object properties
    "keyword-spacing": ["error"], // require a space before & after keywords
    "brace-style": ["error", "1tbs", { "allowSingleLine": true }], // enforce one true brace style
    "space-before-blocks": "error", // require space before blocks
    "curly": ["error", "multi-line", "consistent"], // require curly braces for multiline control statements

    // Cannot import from the same module twice
    "no-duplicate-imports": ["error"],

    // Cannot shadow names
    "no-shadow": ["off"],
    "@typescript-eslint/no-shadow": ["error"],

    // Required spacing in property declarations (copied from TSLint, defaults are good)
    "key-spacing": ["error"],

    // Require semicolons
    "semi": ["error", "always"],

    // Don't unnecessarily quote properties
    "quote-props": ["error", "consistent-as-needed"],

    // No multiple empty lines
    "no-multiple-empty-lines": ["error"],

    // Max line lengths
    "max-len": [
      "error",
      {
        "code": 150,
        "ignoreUrls": true, // Most common reason to disable it
        "ignoreStrings": true, // These are not fantastic but necessary for error messages
        "ignoreTemplateLiterals": true,
        "ignoreComments": true,
        "ignoreRegExpLiterals": true
      }
    ],

    // One of the easiest mistakes to make
    "@typescript-eslint/no-floating-promises": ["error"],

    // Make sure that inside try/catch blocks, promises are 'return await'ed
    // (must disable the base rule as it can report incorrect errors)
    "no-return-await": "off",
    "@typescript-eslint/return-await": "error",

    // Useless diff results
    "no-trailing-spaces": ["error"],

    // Must use foo.bar instead of foo['bar'] if possible
    "dot-notation": ["error"]
  }
}