`datetime.timedelta` Raise Exception about viztracer

[gaogaotiantian]

This is a valid bug.

The problem is that when a class has a class method like __new__ or sometimes _create, it will create the self variable in the method. CodeSnap check against class name via self to match the name of entry and exit.

This bug is fixed in master by ignoring the unmatch when the only difference is class name. This test case will also cause a segfault with c tracer, which is fixed in the same commit.

A regression test is added.

[hfudev]

Another mistake. last line exception. .format(x, y) or f''

[gaogaotiantian]

Hi,

Could you make a minimum script that can reproduce this error? Also what interpreter are you using? Is it CPython or something less common? Did you use Cython? I have never tested the module with Cython.

The Exception string is a valid mistake, thanks!

[hfudev]

Sorry here's a late reply. Just back to the office.

I‘m using CPython 3.8.5 and here's the simplest reproducible script.

# test.py
from datetime import timedelta

a = timedelta(hours=5)

reproduce steps:

1. python -m codesnap test.py
2. Traceback:

Traceback (most recent call last):
  File "/usr/lib/python3.8/runpy.py", line 194, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/usr/lib/python3.8/runpy.py", line 87, in _run_code
    exec(code, run_globals)
  File "xxx/lib/python3.8/site-packages/codesnap/__main__.py", line 21, in <module>
    snap.save()
  File "xxx/lib/python3.8/site-packages/codesnap/codesnap.py", line 20, in save
    self.parse()
  File "xxx/lib/python3.8/site-packages/codesnap/tracer.py", line 50, in parse
    self.snaptree.add_exit(data[1], data[2])
  File "xxx/lib/python3.8/site-packages/codesnap/snaptree.py", line 38, in add_exit
    raise Exception("Function Entry/Exit did not match.{} vs {}", name, self.curr.function_name)
Exception: ('Function Entry/Exit did not match.{} vs {}', 'datetime.timedelta.__new__', 'datetime.__new__')

I didn't look into your code, but I guess the datetime library is using some trick. Maybe you can take a look at it?

[hfudev]

I‘ve tested with pip install -U git+https://github.com/gaogaotiantian/codesnap, the fix seems worked! Thanks for your effort. I'm closing this issue