message: [oracle] fix infinite recursion bug in display
diff: @@ -28,6 +28,6 @@ pub enum ProofError {
  // Implement `Display` for ProofError
  impl fmt::Display for ProofError {
  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
  - write!(f, "({})", self)
  + write!(f, "({:?})", self)
  }
  }
  