Using pytest.set_trace with iPython's TerminalInteractiveShell

[JBKahn]

Hey, I've been doing some fiddling around and haven't been able to make heads or tales of it. When looking at iPython's debugger class, I was able to find a flaw that I thought was causing it but it isn't.

I thought this file was imported at the wrong time, when we were still capturing and _is_tty was the wrong value, but I have verified that even if I hardcode that value, it still falls back to launching a PDB shell instead. I know this is probably more of an iPython issue than a pytest issue but I was wondering if anyone wanted to give me a hand.

This is the way I had tried to use it with the pdbcls arg.
I verified with a print statement in the pip installed package that it was accessing that class.

[JBKahn]

I noticed that if I augment this line to be

        import ipdb;
        ipdb.set_trace(frame)

that works, just trying to figure out how to work that into the class that I'm passing in.

[JBKahn]

passing is giving me an error:
--pdbcls=IPython.terminal.debugger:TerminalPdb
passing this as the class

def Debugger():
    import ipdb
    return ipdb

works and dumps me into a shell but then I cannot recover and it crashes when I try to end the exception

INTERNALERROR> Traceback (most recent call last):
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/_pytest/main.py", line 100, in wrap_session
INTERNALERROR>     session.exitstatus = doit(config, session) or 0
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/_pytest/main.py", line 138, in _main
INTERNALERROR>     config.hook.pytest_runtestloop(session=session)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 617, in __call__
INTERNALERROR>     return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 222, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook, methods, kwargs)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 216, in <lambda>
INTERNALERROR>     firstresult=hook.spec_opts.get('firstresult'),
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 201, in _multicall
INTERNALERROR>     return outcome.get_result()
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 76, in get_result
INTERNALERROR>     raise ex[1].with_traceback(ex[2])
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 180, in _multicall
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/_pytest/main.py", line 161, in pytest_runtestloop
INTERNALERROR>     item.config.hook.pytest_runtest_protocol(item=item, nextitem=nextitem)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 617, in __call__
INTERNALERROR>     return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 222, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook, methods, kwargs)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 216, in <lambda>
INTERNALERROR>     firstresult=hook.spec_opts.get('firstresult'),
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 201, in _multicall
INTERNALERROR>     return outcome.get_result()
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 76, in get_result
INTERNALERROR>     raise ex[1].with_traceback(ex[2])
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 180, in _multicall
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/_pytest/runner.py", line 64, in pytest_runtest_protocol
INTERNALERROR>     nodeid=item.nodeid, location=item.location,
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 617, in __call__
INTERNALERROR>     return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 222, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook, methods, kwargs)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/__init__.py", line 216, in <lambda>
INTERNALERROR>     firstresult=hook.spec_opts.get('firstresult'),
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 201, in _multicall
INTERNALERROR>     return outcome.get_result()
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 76, in get_result
INTERNALERROR>     raise ex[1].with_traceback(ex[2])
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/pluggy/callers.py", line 180, in _multicall
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>   File "/usr/local/lib/python3.6/site-packages/_pytest/terminal.py", line 315, in pytest_runtest_logfinish
INTERNALERROR>     last_item = len(self._progress_nodeids_reported) == self._session.testscollected
INTERNALERROR> AttributeError: 'NoneType' object has no attribute 'testscollected'

[JBKahn]

Seems this issue is somewhat similar to #3170 as downgrading pytest worked. I'll have to identify which caused the failure.

def Debugger():
    import ipdb
    return ipdb

worked as my pdbcls

[nicoddemus]

Hi @JBKahn,

Can you post your failures please?

[JBKahn]

@nicoddemus it was pytest-sugar.

Using

def Debugger():
    import ipdb
    return ipdb

With
--pdbcls=path:Debugger
Work perfectly.

It would be cool if we could potentially pass a class or a module but this isn't a difficult workaround.

[nicoddemus]

OK thanks for the follow up!

[mmospanenko]

Works -s argument for me

[JBKahn]

We don't want to skip capture, so we use the debugger argument because we don't want to use -s