ipdb broken in jupyter notebook on windows 10

[axil]

After a recent update, ipdb does not show current line and context in jupyter notebook anymore. The 'l' command works fine, though. So I have to run 'l' after every single 'n' manually.

def f():
    import ipdb; ipdb.set_trace()
    print('hi')
f()

I've traced down the problem and the source is the direction of the slashes. The function format_stack_entry receives a frame object with mixed slashes: <frame at 0x000001F092B6A388, file 'C:\Users\ASUS\AppData\Local\Temp/ipykernel_20044/714112756.py', line 2, code f>

Then the 'l' command (do_list) queries linecache with this mixed slashes and succeeds, while the print_stack_entry canonizes the filename so that it looks like 'C:\Users\ASUS\AppData\Local\Temp\ipykernel_20044\714112756.py' (note two last slashes are now forward slashes, not backslashes) — and linecache returns an empty list.

Did not dig deeper, but this quick and dirty workaround helps:

--- debugger.py~        2022-02-26 17:51:36.823790800 +0700
+++ debugger.py 2022-02-26 17:51:48.077555800 +0700
@@ -571,7 +571,7 @@
         ret.append(return_value)

         #s = filename + '(' + `lineno` + ')'
-        filename = self.canonic(frame.f_code.co_filename)
+        filename = frame.f_code.co_filename
         link = tpl_link % py3compat.cast_unicode(filename)

         if frame.f_code.co_name:

I ran git blame against IPython/core/debugger.py and this particular line is >10 years old, so it is definitely not the source of the problem, but this fix works for me.

[axil]

Checked with python3.6 and python3.9.

Pip freeze for python3.9 is like this:
argon2-cffi==21.1.0
astor==0.8.1
attrs==21.2.0
autopep8==1.6.0
backcall==0.2.0
bleach==4.1.0
cffi==1.14.6
colorama==0.4.4
debugpy==1.4.3
decorator==5.0.9
defusedxml==0.7.1
entrypoints==0.3
ipdb==0.13.9
ipykernel==6.4.0
ipython==7.27.0
ipython-genutils==0.2.0
jedi==0.18.0
Jinja2==3.0.1
jsonschema==3.2.0
jupyter-client==7.0.2
jupyter-core==4.7.1
jupyterlab-pygments==0.1.2
MarkupSafe==2.0.1
matplotlib-inline==0.1.3
mistune==0.8.4
mypy==0.931
mypy-extensions==0.4.3
nb-mypy==1.0.2
nbclient==0.5.4
nbconvert==6.1.0
nbformat==5.1.3
nest-asyncio==1.5.1
notebook==6.4.3
numpy==1.21.2
packaging==21.0
pandocfilters==1.4.3
parso==0.8.2
pickleshare==0.7.5
prometheus-client==0.11.0
prompt-toolkit==3.0.20
pycodestyle==2.8.0
pycparser==2.20
Pygments==2.10.0
pyparsing==2.4.7
pyrsistent==0.18.0
python-dateutil==2.8.2
pywin32==301
pywinpty==1.1.4
pyzmq==22.2.1
Send2Trash==1.8.0
six==1.16.0
terminado==0.12.1
testpath==0.5.0
toml==0.10.2
tomli==2.0.1
tornado==6.1
traitlets==5.1.0
typing_extensions==4.1.1
wcwidth==0.2.5
webencodings==0.5.1

Python 3.9.7 (64bit). Windows 10 x64 Home Edition.

[MrMino]

I don't have Win10 on hand right now so if someone else could repro this with the same environment it would be great.