rules:
  - id: read-io-eof
    patterns:
                    - pattern: |
                        $N, $ERR := $R.Read(($SLICE : []byte))
                        if $ERR != nil {
                            return ...
                        }
                    - pattern-not: |
                        $N, $ERR := rand.Read(($SLICE : []byte))
                        if $ERR != nil {
                            return ...
                        }
    message: "Read() can return n bytes and io.EOF"
    languages: [go]
    severity: ERROR