debugpy crashing when breakpoints are set on Python 3.13

[will-s-hart]

When trying to debug code in VS Code using cartopy (v0.25.0) with Python 3.13 (on Apple silicon), I'm getting the following exception on importing cartopy when breakpoints are set:

Exception has occurred: AssertionError
<code object _call_with_frames_removed at 0x104ea0570, file "<frozen importlib._bootstrap>", line 480> != <code object PyInit_trace at 0x1199aedb0, file "lib/cartopy/trace.pyx", line 1>
KeyError: (1, 'xx/envs/default/lib/python3.13/site-packages/lib/cartopy/trace.pyx', <code object PyInit_trace at 0x1199aedb0, file "lib/cartopy/trace.pyx", line 1>)

During handling of the above exception, another exception occurred:

  File "xx.py", line 1, in <module>
    import cartopy
AssertionError: <code object _call_with_frames_removed at 0x104ea0570, file "<frozen importlib._bootstrap>", line 480> != <code object PyInit_trace at 0x1199aedb0, file "lib/cartopy/trace.pyx", line 1>

Looking around, seems related to issues that have been reported in other packages using Cython:
#aio-libs/frozenlist#658
#CoolProp/CoolProp#2612

Not sure if this is something that can be fixed in cartopy? Thanks!

[tomvothecoder]

I'm getting the same thing trying to debug a project that uses cartopy (on Linux). Thanks for reporting this @will-s-hart.

[tomvothecoder]

Also related to this: microsoft/vscode-python-debugger#723

[tomvothecoder]

I tried these two workarounds. I'm going with 2) for now until this issue is fix with Python 3.13.

1. Unset all breakpoints before running debugy.py, then set them after it passes the import cartopy code (link) -- You have time when to set the breakpoints, otherwise the error will be raised
2. Use Python 3.12 for now (link) -- easier and quicker fix

[sfinkens]

Another workaround idea: Set breakpoint in the source code and unset breakpoints in vscode.

def method_under_test():
    breakpoint()

[mshumko]

I'm getting the same error using python 3.14. I followed @tomvothecoder's 1st workaround and that works.