Wrap visitor recursion errors in PluginExecutionFailed

[m-aciek]

Refs. #295 (comment)

New UX:

$ uvx --with git+https://github.com/m-aciek/flake8-bugbear.git@copilot%2Fwrap-recursionerror-in-flake8-exception flake8
sympy/polys/numberfields/resolvent_lookup.py: "flake8-bugbear" failed during execution due to RecursionError('maximum recursion depth exceeded')
Run flake8 with greater verbosity to see more details

Previous UX:

$ uvx --with flake8-bugbear flake8
[… long stacktrace]
    return visitor(node)                                                                                                                                                                                         
  File "~/.local/share/uv/python/cpython-3.14.0-macos-x86_64-none/lib/python3.14/ast.py", line 516, in generic_visit                                                                            
    self.visit(value)                                                                                                                                                                                            
    ~~~~~~~~~~^^^^^^^                                                                                                                                                                                            
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/lib/python3.14/site-packages/bugbear.py", line 455, in visit                                                                                    
    super().visit(node)                                                                                                                                                                                          
    ~~~~~~~~~~~~~^^^^^^                                                                                                                                                                                          
  File "~/.local/share/uv/python/cpython-3.14.0-macos-x86_64-none/lib/python3.14/ast.py", line 506, in visit                                                                                    
    return visitor(node)                                                                                                                                                                                         
  File "~/.local/share/uv/python/cpython-3.14.0-macos-x86_64-none/lib/python3.14/ast.py", line 516, in generic_visit                                                                            
    self.visit(value)                                                                                                                                                                                            
    ~~~~~~~~~~^^^^^^^                                                                                                                                                                                            
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/lib/python3.14/site-packages/bugbear.py", line 455, in visit                                                                                    
    super().visit(node)                                                                                                                                                                                          
    ~~~~~~~~~~~~~^^^^^^                                                                                                                                                                                          
  File "~/.local/share/uv/python/cpython-3.14.0-macos-x86_64-none/lib/python3.14/ast.py", line 506, in visit                                                                                    
    return visitor(node)                                                                                                                                                                                         
  File "~/.local/share/uv/python/cpython-3.14.0-macos-x86_64-none/lib/python3.14/ast.py", line 510, in generic_visit                                                                            
    for field, value in iter_fields(node):                                                                                                                                                                       
                        ~~~~~~~~~~~^^^^^^                                                                                                                                                                        
RecursionError: maximum recursion depth exceeded                                                                                                                                                                 
"""                                                                                                                                                                                                              

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/bin/flake8", line 12, in <module>
    sys.exit(main())
             ~~~~^^
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/lib/python3.14/site-packages/flake8/main/cli.py", line 23, in main
    app.run(argv)
    ~~~~~~~^^^^^^
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/lib/python3.14/site-packages/flake8/main/application.py", line 198, in run
    self._run(argv)
    ~~~~~~~~~^^^^^^
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/lib/python3.14/site-packages/flake8/main/application.py", line 187, in _run
    self.run_checks()
    ~~~~~~~~~~~~~~~^^
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/lib/python3.14/site-packages/flake8/main/application.py", line 103, in run_checks
    self.file_checker_manager.run()
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/lib/python3.14/site-packages/flake8/checker.py", line 235, in run
    self.run_parallel()
    ~~~~~~~~~~~~~~~~~^^
  File "~/.cache/uv/archive-v0/DcgALyZzrPwYWWKQ/lib/python3.14/site-packages/flake8/checker.py", line 204, in run_parallel
    self.results = list(pool.imap_unordered(_mp_run, self.filenames))
                   ~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "~/.local/share/uv/python/cpython-3.14.0-macos-x86_64-none/lib/python3.14/multiprocessing/pool.py", line 873, in next
    raise value
RecursionError: maximum recursion depth exceeded

[Copilot]

Pull request overview

This PR improves flake8-bugbear’s failure UX by converting AST visitor recursion overflows into a flake8.exceptions.PluginExecutionFailed, so Flake8 can present a short “plugin failed” message instead of dumping a long stack trace.

Changes:

• Wrap exceptions raised during BugBearVisitor.visit() in PluginExecutionFailed to improve Flake8’s user-facing error output.
• Add a unit test asserting that a RecursionError is wrapped correctly and preserves filename/plugin metadata.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
bugbear.py	Wraps visitor execution failures in PluginExecutionFailed so Flake8 can report a concise plugin error.
tests/test_bugbear.py	Adds coverage ensuring RecursionError is wrapped with correct metadata.

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[cooperlees]

Many thanks for this! A clearer error now.