alvis/presetter

extends:
  - plugin:@typescript-eslint/recommended-requiring-type-checking
  - plugin:sonarjs/recommended # code quality
parserOptions:
  project: tsconfig.json
  sourceType: module
plugins:
  - header # enforce a header in each source file
  - no-secrets # check if there's any secret left in the code
rules:
  # ECMAScript
  '@typescript-eslint/prefer-nullish-coalescing': warn # simplify a logic by using the nullish coalescing operator

  # Stylistic Issues
  header/header: off

  # Best Practices
  '@typescript-eslint/no-base-to-string': error # disallow Object.toString() which returns the meaningless [object Object]
  '@typescript-eslint/promise-function-async': warn # ensure any function that returns a promise to be marked async for better readability
  '@typescript-eslint/return-await': error # return an awaited promised in the try catch block for better stack trace
  '@typescript-eslint/no-unnecessary-condition': error # reduce the complexity of a piece of code by removing redundant logic
  curly: error # all control statement must be enclosed by a curly bracket
  default-case: error # ensure a default case in any switch

  # Code Quality
  '@typescript-eslint/no-unused-expressions': # unused expressions must be at least commented
    - warn
    - allowShortCircuit: true
      allowTernary: true
  '@typescript-eslint/prefer-function-type': warn # make a function a function instead of an interface
  '@typescript-eslint/unified-signatures': warn # simplify an overloading signature
  no-secrets/no-secrets: error # no sensitive information
  sonarjs/cognitive-complexity: # ensure a function is intuitively understandable
    - warn
    - 5
  sonarjs/no-small-switch: off # sometimes you prefer switch than if for extension and better readability
  complexity: warn # limit cyclomatic complexity in a function
  max-lines: # it's hard to follow a large file
    - warn
    - max: 250
      skipBlankLines: true
      skipComments: true
  max-lines-per-function: # it's hard to follow a long function
    - warn
    - max: 30
      skipBlankLines: true
      skipComments: true
      IIFEs: true
  no-console: warn # console is often used for debug, but it can leak sensitive information
  no-eval: error # eval is evil

  # Error Prevention
  '@typescript-eslint/no-misused-promises': # ensure that there's an await before a promise
    - warn
    - checksVoidReturn: false