Better handling of exception groups

[antonpirker]

Properly handle grouped and chained exceptions. The test case in the linked issue illustrates that some ExceptionGroups have been handled in a wrong way.

Updated some tests, because now that those are handled correctly all the mechanism types except for the root exception are set to "chained" like described in the RFC: https://github.com/getsentry/rfcs/blob/main/text/0079-exception-groups.md#interpretation

Because this will change the grouping of exiting Sentry Issues containing ExceptionGroups, it is safer to release this fix in the next major and make sure that we describe the change in behavior in the changelog. (Note: The grouping in the Ariadne issues will not change because those are not ExceptionGroups and only updating the mechanism.type does not change the grouping)

Fixes #3913

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.58%. Comparing base (65132ba) to head (72f3f84).

✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4117      +/-   ##
==========================================
- Coverage   79.58%   79.58%   -0.01%     
==========================================
  Files         141      141              
  Lines       15723    15721       -2     
  Branches     2673     2672       -1     
==========================================
- Hits        12513    12511       -2     
+ Misses       2367     2365       -2     
- Partials      843      845       +2     

Files with missing lines	Coverage Δ
sentry_sdk/utils.py	84.44% <100.00%> (+0.45%)	⬆️

... and 3 files with indirect coverage changes

[szokeasaurusrex]

@antonpirker I think I am generally lacking context in this part of the codebase, so I am struggling to understand how exactly this PR changes the exception grouping behavior.

A walkthrough or technical explanation of how the changes work might help. Although, I suppose it is not urgent, since we will wait for a major release, anyways.

[szokeasaurusrex]

[question] does the exceptions_from_error function already internally handle the non-exception group case?

From naively looking at the diff, it seems that the code for handling exceptions which are not exception groups has been deleted, so I am just wondering where this logic is handled now.

[antonpirker]

I have now updated the code to make it easier to grasp what is happening. (The diff is very hard to read, just checkout the file)

The function exceptions_from_error handles all the cases, single exceptions, chained exceptions and exception groups. It walks through the complete tree of exceptions.

(We can in another PR also think about removing walk_exception_chain everywhere and just use exceptions_from_error for everything. But this is outside of the scope of this PR)

[sentrivana]

I took a look too and have the same questions as Daniel.

OT: we can change the base of this to potel-base so that it gets released with the next major.

[antonpirker]

I am closing this in favor of this PR that will be merged into potel-base:
#4164