simulateTransaction RPC incorrent response

[kalaninja]

Problem

According to documentation the errors of transaction simulation are supposed to be returned inside err field. If signature verification fails it should probably be returned as SignatureFailure. But it is returned as an rpc error:

curl https://api.devnet.solana.com -s -X POST -H "Content-Type: application/json" -d '
  {
    "jsonrpc": "2.0",
    "id": 1,
    "method": "simulateTransaction",
    "params": [
      "AfdiIh1VJVFHoZirs4OV3QgbI9V09KI/Iqotz+kuuWIjg4uwOvZWpb5Ko2FpFbi+QjmRBxkNV4lUmfgYkaGp614BAAEDtXNbCOnvYthBmiJo0S/5JMGj2g1Z6lcS7aM8k9n4Ik7Ee6OvBADQGFw/1hMiY7ym3f4iop/7XcsALwYRoNt9LAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABAgIAAQwCAAAAQEIPAAAAAAA=",
      {
        "encoding":"base64",
        "sigVerify":true
      }
    ]
  }
'

{"jsonrpc":"2.0","error":{"code":-32003,"message":"Transaction signature verification failure"},"id":1}

Proposed Solution

Either the response or the documentation should be fixed.