Call stacks containing <anonymous> source fail to symbolicate

[samuelmaddock]

Environment

macOS 15.2 ARM64

Steps to Reproduce

1. Format a call stack received from the Crash Reporting API

Error: Example unresponsive call stack
    at Object.hasOwnProperty (<anonymous>)

2. Submit it to the /symbolicate-js endpoint

{
  "platform": "node",
  "source": {
    "id": "<id>",
    "url": "https://sentry.io/api/0/projects/sentry-org/sentry-project/artifact-lookup/",
    "token": "secret"
  },
  "stacktraces": [
    {
      "frames": [
        {
          "function": "Object.hasOwnProperty",
          "in_app": false
        }
      ]
    }
  ],
  "dist": "production",
  "release": "1.33.1",
  "scraping": {
    "enabled": true,
    "allowed_origins": [
      "*"
    ],
    "headers": {}
  }
}

Expected Result

The call stack is returned with a partially symbolicated call stack.

Actual Result

Failed to deserialize the JSON body into the target type: stacktraces[0].frames[0]: missing field `abs_path` at line 1 column 220

Additional Background

I'm investigating collecting unresponsive renderer call stacks in Sentry using the new Crash Reporting API. This relates to the work @timfish initiated in getsentry/sentry-javascript#14044

The first line of the call stacks contain the <anonymous> source. Whether this is expected or not, it'd be great if the symbolicator service could handle this case so the call stacks can be symbolicated.

---

I found the code within V8 which handles formatting JS call stacks.
https://source.chromium.org/chromium/chromium/src/+/main:v8/src/objects/call-site-info.cc;l=688-718;drc=763100e0bf9a25ba6f203612af5a4331fbd2d048

According to the implementation of AppendFileLocation, it can output <anonymous> by itself if there's no line number associated with the frame.

[loewenheim]

Hi, Symbolicator is currently set up in such a way that you can't send it frames which it will definitely not be able to process. JS frames without an abs_path and line number are one such case. Would it be an option for you to filter these frames out beforehand?

[samuelmaddock]

@loewenheim It's technically possible to pre-process the stack traces in my case (using Electron). In other cases though, browser crash reports (getsentry/sentry#38940) are sent directly from the browser without a chance to process them before reaching sentry/relay servers.

I pulled down symbolicator locally and made the necessary changes for this as well #1581