Bug: There are two bugs in the RPC error handling.

[clint419]

[2023-12-02T06:05:37Z TRACE starknet_providers::jsonrpc::transports::http] Response from JSON-RPC: {"jsonrpc":"2.0","error":{"code":-32603,"message":"Internal error","data":{"error":"Internal error: Error in the called contract (0x05686c52b6f38639eb9cfb3dfff1b3260315099aa045fcc0b4a865068ba36aad):\nError at pc=0:558:\nCouldn't compute operand op1. Unknown value for memory cell 7:5"}},"id":1}

called `Result::unwrap()` on an `Err` value: Provider(Other(TransportError(Json(Error("data did not match any variant of untagged enum JsonRpcResponse", line: 0, column: 0)))))

[clint419]

@xJonathanLEI

[clint419]

Sequencer gateway error handling implementation bug:

[2023-12-02T07:39:04Z TRACE starknet_providers::sequencer] Response from sequencer API: {"code": "StarknetErrorCode.DEPRECATED_ENDPOINT", "message": "Endpoint is deprecated from version 0.12.3."}
thread 'main' panicked at examples/mint_tokens.rs:65:10:
called `Result::unwrap()` on an `Err` value: Provider(Other(Serde(Error("data did not match any variant of untagged enum RawFieldElementResponse", line: 0, column: 0))))

[xJonathanLEI]

For the original issue reported: you're using a JSON-RPC v0.4.x endpoint, which reports contract errors under the code -32603. Starknet-rs now works with JSON-RPC v0.5.1, which would instead report it under code 40.

For the 2nd issue, it's due to Starkware upgrading the Goerli testnet to v0.12.3 and deprecating most endpoints. At this point, using the sequencer gateway is almost pointless. The implementation of Provider for SequencerGatewayProvider will be removed in the next version.

[xJonathanLEI]

For the original issue, check out the support for error data introduced in #513.