waitgroup-add-called-inside-goroutine.yml

rules:
- id: waitgroup-add-called-inside-goroutine
  patterns:
    - pattern-either: 
      - pattern: |
          $WG := &sync.WaitGroup{}
          ...
          go func(...) {
            ...
            $WG.Add(...)
            ...
          }(...)
          ...
          $WG.Wait()
      - pattern: |
          var $WG sync.WaitGroup
          ...
          go func(...) {
            ...
            $WG.Add(...)
            ...
          }(...)
          ...
          $WG.Wait()
    - pattern-not-inside: |
        for ... {
          ...
          $WG.Add(...)
          ...
        }
  message: |
    Calling `$WG.Add` inside of an anonymous goroutine may result in `$WG.Wait`
    waiting for more or less calls to `$WG.Done()` than expected.
  languages: [go]
  severity: ERROR