Incorrect gasUsed in callTracer

[quickchase]

System information

Geth version: Geth/v1.101311.0-stable-e9a306ba/linux-amd64/go1.21.9
CL client & version: op-node v1.7.3
OS & Version:Linux

Issue

Given the following call:

{"id":"synth","jsonrpc":"2.0","method":"debug_traceTransaction","params":["0xc93e9c095619a713a1e29557d8a51a7f020844b3b97c549f6c3e1da721fba115",{"tracer":"callTracer"}]}

op-geth is returning:

{
  "jsonrpc": "2.0",
  "id": "synth",
  "result": {
    "from": "0xdeaddeaddeaddeaddeaddeaddeaddeaddead0001",
    "gas": "0xf4240",
    "gasUsed": "0xf4240",
    "to": "0x4200000000000000000000000000000000000015",
    "input": "0x440a5e2000000558000c5fc500000000000000030000000066197f4b00000000012bb4050000000000000000000000000000000000000000000000000000002e4cb91cea000000000000000000000000000000000000000000000000000000000000000145a826de7841ea76c056554f1c351464a964420e8283b88a1762549f987e688c0000000000000000000000006887246668a3b87f54deb3b94ba47a6f63f32985",
    "calls": [
      {
        "from": "0x4200000000000000000000000000000000000015",
        "gas": "0xe9b69",
        "gasUsed": "0x3fac",
        "to": "0x07dbe8500fc591d1852b76fee44d5a05e13097ff",
        "input": "0x440a5e2000000558000c5fc500000000000000030000000066197f4b00000000012bb4050000000000000000000000000000000000000000000000000000002e4cb91cea000000000000000000000000000000000000000000000000000000000000000145a826de7841ea76c056554f1c351464a964420e8283b88a1762549f987e688c0000000000000000000000006887246668a3b87f54deb3b94ba47a6f63f32985",
        "value": "0x0",
        "type": "DELEGATECALL"
      }
    ],
    "value": "0x0",
    "type": "CALL"
  }
}

However, the gasUsed is incorrect, if you look at the receipt:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "blockHash": "0x5cf34d3f6ec2dae3c78a5dd9e89a8dad5d139f91983ce91aa0f75ece0ada1bb9",
    "blockNumber": "0x712d12d",
    "contractAddress": null,
    "cumulativeGasUsed": "0xab4b",
    "depositNonce": "0xcd0eb6",
    "depositReceiptVersion": "0x1",
    "effectiveGasPrice": "0x0",
    "from": "0xdeaddeaddeaddeaddeaddeaddeaddeaddead0001",
    "gasUsed": "0xab4b",
    "logs": [],
    "logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
    "status": "0x1",
    "to": "0x4200000000000000000000000000000000000015",
    "transactionHash": "0xd8fca681d83ef12ebf44a31dafad3431b5cfcb8f7490851c8d4337085a99a38d",
    "transactionIndex": "0x0",
    "type": "0x7e"
  }
}

This is how much gas is used: "cumulativeGasUsed": "0xab4b", NOT 0xf4240

Both op-erigon and the explorer say that the output of the debug_traceTransaction should be "gasUsed": "0xab4b",

[protolambda]

Found the issue: see

op-geth/core/state_transition.go

Line 442 in 9e50b7d

tracer.CaptureTxEnd(0)

When the tracer reports gasUsed, it reports it based on the gasUsed that was determined based on remaining gas in CaptureTxEnd. For deposits we don't have refunds, hence 0 remaining gas. But that doesn't mean all gas was used. Hence the incorrect tracer value.

In the implementation the gas-price is 0, and so a 0 refund is given to deposits, without skipping the refund code-path.

I think we can reduce the diff, and just report the actual remainingGas to the tracer.
Would like some feedback here from @trianglesphere and/or @axelKingsley.

[trianglesphere]

@smartcontracts actually added the CaptureTxEnd(0) pretty recently to handle the case of failed deposit transactions.

[quickchase]

Bump 🙇‍♂️