Make rich.traceback capable of handling Exception objects which are RichRenderable

[pradyunsg]

In a few of the projects I've been working on (pip, sphinx-theme-builder and more), I have been creating "rich-aware" errors -- i.e. these error objects are RichRenderable, by implementing the __rich_console__/__rich__ methods.

It would be really nice if rich.traceback were to use the "rich" representation of those errors (falling back to <error rendering {exc.__class__.__name__}>, like it does with str calls currently).

This would make it possible to switch to using Rich's traceback handler exclusively, allowing for nicer tracebacks for users while still presenting the RichRenderable exception objects in a pretty manner, instead of degrading those to plain strings. :)

[willmcgugan]

So you make the exceptions themselves renderable? I do something similar in Textual.

I guess you always want the traceback, but with the exception rendered if it is renderable?

[pradyunsg]

So you make the exceptions themselves renderable?

Yes. https://github.com/pradyunsg/sphinx-theme-builder/blob/b43870f8db9a47e3c81f2244bb0e8ec0b2a33f3a/src/sphinx_theme_builder/_internal/errors.py#L80

I guess you always want the traceback, but with the exception rendered if it is renderable?

Yes. #2441 would be nice as well, but we'd chatted briefly about that back when pip added rich into it.

[willmcgugan]

Up for a PR? I'm unlikely to get to that in the short term.

I'd also accept a PR for a no-panel switch on Traceback. Probably not a "empty" box though, as that will add whitespace and I'll get folk complaining about that.

[pradyunsg]

I'll give it a shot today. If I don't file a PR in the next ~24 hours, consider this up for grabs. :)

[pradyunsg]

(FWIW, I've reported the other message as spam, via GitHub support)

[pradyunsg]

OK, I finally came around to this. #3325 is the PR, and it works!

[pradyunsg]

Also I've filed #3324 -- a somewhat-unrelated PR that cleans up some dead code from traceback tests.