Big projects lead to `Propagating panic for cycle head that panicked in an earlier execution in that revision` in lsp features, specifically auto import

[Wade-Roberts]

Summary

Some context from VS Code server logs:

2026-04-16 16:02:48.513105285  INFO Version: 0.0.31
2026-04-16 16:02:48.527272881  INFO Defaulting to python-platform `linux`
2026-04-16 16:02:48.527636881  INFO Python version: Python 3.12, platform: linux

In my smaller projects where I use uv, auto-import works fine, e.g.

When I'm working in a large workspace based monorepo though, I get this in the server logs when I try to inspect the actions on an unresolved import error:

2026-04-16 16:04:23.886670807  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:04:23.886672182  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:04:23.886715182  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:04:23.886726057  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:04:23.886857057  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:04:23.905581364  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
...

Version

0.0.31

[MichaReiser]

Thanks for reporting.

Is there any earlier log message that would indicate that ty panicked (crashed)? Unless there's a bug, this message should only be logged after an earlier crash.

[Wade-Roberts]

That is all that I can see in the logs @MichaReiser :

2026-04-16 16:13:34.737591525  INFO Version: 0.0.31
2026-04-16 16:13:34.922009721  INFO Defaulting to python-platform `linux`
2026-04-16 16:13:34.922207138  INFO Python version: Python 3.12, platform: linux
2026-04-16 16:13:35.391634697  INFO Checking file `[redacted]` took more than 100ms (202.574295ms)
2026-04-16 16:18:47.216277675  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:18:47.216309966  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:18:47.216272925  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:18:47.216272383  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:18:47.216270591  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:18:47.225665975  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:01.913317943  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:01.913368235  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:01.913377985  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:01.913387068  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:01.913317818  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:01.962251488  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:05.365535057  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:05.365594599  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:05.365535057  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:05.365578766  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:05.365535057  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision
2026-04-16 16:19:05.417096730  WARN Propagating panic for cycle head that panicked in an earlier execution in that revision

Maybe I can try more verbose logging?

[MichaReiser]

Can you see any diagnostics in the errors panel with the ID "panic"? Or can you run the CLI (ty check) and see if it reports any panic diagnostics (it should also log a warning that it panicked).

We could probably do a better job by potentially logging a warning if that happens