rules:
  - id: err-nil-check
    patterns:
        - pattern-either:
              - pattern: |
                      if err != nil {
                              return err
                      }
                      return nil
              - pattern: |
                      if err != nil {
                              return $X, err
                      }
                      return $X, nil
    message: "superfluous nil err check before return"
    languages: [go]
    severity: ERROR