.eslintrc

{
  "root": true,
  "parser": "@typescript-eslint/parser",
  "parserOptions": {
    "ecmaVersion": 2018,
    "sourceType": "module",
    "project": "tsconfig.json",
    "warnOnUnsupportedTypeScriptVersion": false
  },
  "plugins": ["@typescript-eslint", "jest", "prettier"],
  "extends": [
    "plugin:@typescript-eslint/recommended",
    "prettier/@typescript-eslint"
  ],
  "rules": {
    "no-unused-expressions": "off",
    "require-await": "off",
    "prefer-promise-reject-errors": "error",
    "@typescript-eslint/no-non-null-assertion": "error",
    "@typescript-eslint/explicit-function-return-type": [
      "error",
      {
        "allowExpressions": true,
        "allowTypedFunctionExpressions": true,
        "allowHigherOrderFunctions": true,
        "allowConciseArrowFunctionExpressionsStartingWithVoid": true
      }
    ],
    "prettier/prettier": [
      "error",
      {
        "tabWidth": 2,
        "useTabs": false,
        "semi": false,
        "singleQuote": true,
        "trailingComma": "all",
        "printWidth": 110
      }
    ],
    "@typescript-eslint/no-unused-vars": [
      "error",
      { "ignoreRestSiblings": true }
    ],
    "@typescript-eslint/no-unused-expressions": [
      "error",
      {
        "allowShortCircuit": true,
        "allowTernary": true
      }
    ],
    "@typescript-eslint/require-await": "error",
    "@typescript-eslint/no-floating-promises": "error"
  },
  "overrides": [
    {
      "files": ["**/*.spec.ts", "jest-extensions.ts"],
      "rules": {
        "@typescript-eslint/no-non-null-assertion": "off",
        "@typescript-eslint/explicit-function-return-type": "off"
      }
    }
  ]
}