The mermaid renderer can fail to render certain diagrams, and we already
have a fallback for that. It's not worth crashing Zed over it.
Wrapping `catch_unwind` alone doesn't work because our panic hooks
terminate the process before unwinding begins (we intentionally
terminate so the crash handler subprocess can generate a minidump), so
there was no way to gracefully handle panics from third-party code until
now (in rare cases where we need it, like in this case).
To handle this gracefully, we added `crashes::recoverable_panic` which
tells the panic hook to stand down on the current thread so the unwind
can proceed and be caught. This should be used sparingly since caught
panics bypass crash reporting.
Release Notes:
- Fixed a crash when rendering mermaid diagrams in markdown preview.
Smit Barmase
c56dcef972