[PyCharm Community 2019.1.3] Debug view for pytest freeze and can't access variables

When I wants to debug some pytest, the view appear, the app is working, I can set breakpoint and step into it.

Except I can't see variables values, I cant' access a debug console with the proper context.

There is something looping forever somewhere, see attached file.

Any idea?

0
19 comments

Does the issue reproduce with any test script? Please try some simple example, to determine if it's related to your scripts.

Then, please set `PYCHARM_DEBUG=True` env variable in your pytest configuration, run the debugger - it should show the extended output in the console, please paste here.

0
Avatar
Thierry Chantier

When trying to reproduce, I created a new project dedicated to this issue.

And I remember that my original source was on a project that is mainly a Java app, with this folder containing some python helpers.

So I modified the original project to have a separate Python env and just imported pytest (and boto3 because it is a AWS helper script)

And now everything works.

I'll try later to reproduce in another project, using my system python env. Maybe there is something wrong in it.

But I have a solution to my initial issue.

0

Ok, glad to hear it's working. If the issue reproduces again, you can try disabling cython speedups, which can cause peformance issues in rare cases. To do that, set the following env variables to your test configuration:

PYDEVD_USE_CYTHON=NO
PYDEVD_USE_FRAME_EVAL=NO

1

I have the same issue on PyCharn pro 2020.2. Starting with a fresh project and a very simple dummy test:

def test_var():

t = 1
assert t == 1

Setting a breakpoint works, the program hold, but PyCharm can't resolve variables (hangs on "Collecting data...") and the console won't print. Here is the console output when trying to do things:

 

/home/mowglie/.pyenv/versions/py3/bin/python /home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/pydev/pydevd.py --multiproc --qt-support=auto --client 127.0.0.1 --port 41727 --file /home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/pycharm/_jb_pytest_runner.py --target test_dummy.py::test_var -- -s
Executing PyCharm's `sitecustomize`
User doesn't have a custom `sitecustomize`
Custom matplotlib backend was set for SciView
Using Cython speedups
Unable to load jupyter_debug plugin
Executing file /home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/pycharm/_jb_pytest_runner.py
arguments: ['/home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/pycharm/_jb_pytest_runner.py', '--target', 'test_dummy.py::test_var', '--', '-s']
PYDEVD_FILTER_LIBRARIES False
Started in multiproc mode
('Connecting to ', '127.0.0.1', ':', '41727')
('Connected.',)
debugger: received >>99 -1 35547
<<
Received command: ??? 99 -1 35547
Received port 35547
pydev debugger: process 12882 is connecting
('Connecting to ', '127.0.0.1', ':', '35547')
('Connected.',)
debugger: received >>501 1 0.1 UNIX
<<
Received command: CMD_VERSION 501 1 0.1 UNIX
sending cmd --> CMD_VERSION @@BUILD_NUMBER@@
Connected to pydev debugger (build 202.7319.64)
debugger: received >>111 3 python-line /home/mowglie/PycharmProjects/pythonProject/test_dummy.py 5 test_var THREAD None None
<<
Received command: CMD_SET_BREAK 111 3 python-line /home/mowglie/PycharmProjects/pythonProject/test_dummy.py 5 test_var THREAD None None
Added breakpoint:/home/mowglie/PycharmProjects/pythonProject/test_dummy.py - line:5 - func_name:b'test_var'
debugger: received >>170 11 SET_UNIT_TESTS_DEBUGGING_MODE
146 7 SHOW_RETURN_VALUES 0
101 9
122 5 python-BaseException None None 0 1 0
<<
Received command: ??? 170 11 SET_UNIT_TESTS_DEBUGGING_MODE
Received command: CMD_SHOW_RETURN_VALUES 146 7 SHOW_RETURN_VALUES 0
Show return values: False
Received command: CMD_RUN 101 9
Received command: CMD_ADD_EXCEPTION_BREAK 122 5 python-BaseException None None 0 1 0
Exceptions to hook on terminate: {'BaseException': <_pydevd_bundle.pydevd_breakpoints.ExceptionBreakpoint object at 0x7fdc06f38e80>}
sending cmd --> CMD_THREAD_CREATE <xml><thread name="MainThread" id="pid_12882_id_140583053184448" /></xml>
IDE_PROJECT_ROOTS ['/home/mowglie/PycharmProjects/pythonProject']
LIBRARY_ROOTS ['/home/mowglie/.pyenv/versions/3.8.5/lib/python3.8', '/home/mowglie/.pyenv/versions/3.8.5/lib/python3.8/lib-dynload', '/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages', '/home/mowglie/disk/Dropbox/HomeDocs/git/salem', '/home/mowglie/disk/Dropbox/HomeDocs/git/oggm-fork', '/home/mowglie/.cache/JetBrains/PyCharm2020.2/python_stubs/551278590', '/home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/python-skeletons', '/home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/typeshed/stdlib/3.7', '/home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/typeshed/stdlib/3', '/home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/typeshed/stdlib/2and3', '/home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/typeshed/third_party/3', '/home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/typeshed/third_party/2and3']
Launching pytest with arguments -s test_dummy.py::test_var in /home/mowglie/PycharmProjects/pythonProject
Patching args: ['/sbin/ldconfig', '-p']
Process is not python, returning.
sending cmd --> CMD_PROCESS_CREATED <process/>
=== Scientific View debug enabled ===
sending cmd --> CMD_PROCESS_CREATED <process/>
('Connecting to ', '127.0.0.1', ':', '41727')
('Connected.',)
("The debugger thread 'DispatchReader' is traced which may lead to debugging performance issues.",)
debugger: received >>99 -1 43425
<<
Received command: ??? 99 -1 43425
PYDEVD_FILTER_LIBRARIES False
('Connecting to ', '127.0.0.1', ':', '43425')
('Connected.',)
debugger: received >>501 1 0.1 UNIX
<<
Received command: CMD_VERSION 501 1 0.1 UNIX
sending cmd --> CMD_VERSION @@BUILD_NUMBER@@
debugger: received >>111 3 python-line /home/mowglie/PycharmProjects/pythonProject/test_dummy.py 5 test_var THREAD None None
<<
Received command: CMD_SET_BREAK 111 3 python-line /home/mowglie/PycharmProjects/pythonProject/test_dummy.py 5 test_var THREAD None None
debugger: received >>111 13 python-line /home/mowglie/PycharmProjects/pythonProject/test_dummy.py 5 test_var THREAD None None
<<
Received command: CMD_SET_BREAK 111 13 python-line /home/mowglie/PycharmProjects/pythonProject/test_dummy.py 5 test_var THREAD None None
Added breakpoint:/home/mowglie/PycharmProjects/pythonProject/test_dummy.py - line:5 - func_name:b'test_var'
debugger: received >>122 5 python-BaseException None None 0 1 0
<<
Received command: CMD_ADD_EXCEPTION_BREAK 122 5 python-BaseException None None 0 1 0
Added breakpoint:/home/mowglie/PycharmProjects/pythonProject/test_dummy.py - line:5 - func_name:b'test_var'
Exceptions to hook on terminate: {'BaseException': <_pydevd_bundle.pydevd_breakpoints.ExceptionBreakpoint object at 0x7fdbada823a0>}
debugger: received >>146 7 SHOW_RETURN_VALUES 0
170 11 SET_UNIT_TESTS_DEBUGGING_MODE
101 9
<<
Received command: CMD_SHOW_RETURN_VALUES 146 7 SHOW_RETURN_VALUES 0
Show return values: False
Received command: ??? 170 11 SET_UNIT_TESTS_DEBUGGING_MODE
Received command: CMD_RUN 101 9
debugger: received >>122 15 python-BaseException None None 0 1 0
170 17 SET_UNIT_TESTS_DEBUGGING_MODE
146 19 SHOW_RETURN_VALUES 0
<<
Received command: CMD_ADD_EXCEPTION_BREAK 122 15 python-BaseException None None 0 1 0
Exceptions to hook on terminate: {'BaseException': <_pydevd_bundle.pydevd_breakpoints.ExceptionBreakpoint object at 0x7fdbf64072e0>}
Received command: ??? 170 17 SET_UNIT_TESTS_DEBUGGING_MODE
Received command: CMD_SHOW_RETURN_VALUES 146 19 SHOW_RETURN_VALUES 0
Show return values: False
sending cmd --> CMD_THREAD_CREATE <xml><thread name="Thread-11" id="pid_12912_id_140581488043632" /></xml>
sending cmd --> CMD_THREAD_CREATE <xml><thread name="Thread-12" id="pid_12912_id_140581488045600" /></xml>
sending cmd --> CMD_THREAD_KILL pid_12912_id_140581488045600
sending cmd --> CMD_THREAD_CREATE <xml><thread name="Thread-13" id="pid_12912_id_140581488045696" /></xml>
sending cmd --> CMD_THREAD_KILL pid_12912_id_140581488045696
sending cmd --> CMD_THREAD_CREATE <xml><thread name="Thread-14" id="pid_12912_id_140581633657008" /></xml>
sending cmd --> CMD_THREAD_KILL pid_12912_id_140581633657008
sending cmd --> CMD_THREAD_CREATE <xml><thread name="MainThread" id="pid_12882_id_140583053184448" /></xml>
============================= test session starts ==============================
platform linux -- Python 3.8.5, pytest-6.0.2, py-1.9.0, pluggy-0.13.1 -- /home/mowglie/.pyenv/versions/py3/bin/python
cachedir: .pytest_cache
Matplotlib: 3.3.2
Freetype: 2.6.1
rootdir: /home/mowglie/PycharmProjects/pythonProject
plugins: mpl-0.122, oggm-1.3.2.dev95+gc05d330
collecting ... collected 1 item
test_dummy.py::test_var Suspending at breakpoint in file: /home/mowglie/PycharmProjects/pythonProject/test_dummy.py on line 5
sending cmd --> CMD_THREAD_SUSPEND <xml><thread id="pid_12882_id_140583053184448" stop_reason="111" message="" suspend_type="frame_eval"><frame id="140582185093536" name="test_var" file="/home/mowglie/PycharmProjects/pythonProject/test_dummy.py" line="5"></frame><frame id="140582185125248" name="pytest_pyfunc_call" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/python.py" line="180"></frame><frame id="94234090882784" name="_multicall" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/callers.py" line="187"></frame><frame id="140582185028848" name="&lt;lambda&gt;" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="84"></frame><frame id="140582185028384" name="_hookexec" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="93"></frame><frame id="140582185054272" name="__call__" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/hooks.py" line="286"></frame><frame id="140582185120640" name="runtest" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/python.py" line="1570"></frame><frame id="94234090877504" name="pytest_runtest_call" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/runner.py" line="153"></frame><frame id="94234090882144" name="_multicall" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/callers.py" line="187"></frame><frame id="140582185027920" name="&lt;lambda&gt;" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="84"></frame><frame id="140582185027456" name="_hookexec" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="93"></frame><frame id="140582185026992" name="__call__" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/hooks.py" line="286"></frame><frame id="140582185070144" name="&lt;lambda&gt;" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/runner.py" line="247"></frame><frame id="94234090804336" name="from_call" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/runner.py" line="294"></frame><frame id="140582185091136" name="call_runtest_hook" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/runner.py" line="246"></frame><frame id="140582185041248" name="call_and_report" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/runner.py" line="207"></frame><frame id="94234090878144" name="runtestprotocol" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/runner.py" line="117"></frame><frame id="140582185066560" name="pytest_runtest_protocol" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/runner.py" line="100"></frame><frame id="94234090876864" name="_multicall" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/callers.py" line="187"></frame><frame id="140582184987888" name="&lt;lambda&gt;" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="84"></frame><frame id="94234090777440" name="_hookexec" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="93"></frame><frame id="140582185300960" name="__call__" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/hooks.py" line="286"></frame><frame id="94234090730336" name="pytest_runtestloop" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/main.py" line="321"></frame><frame id="94234090876224" name="_multicall" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/callers.py" line="187"></frame><frame id="140582185078000" name="&lt;lambda&gt;" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="84"></frame><frame id="140582185077536" name="_hookexec" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="93"></frame><frame id="140582185077072" name="__call__" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/hooks.py" line="286"></frame><frame id="140582671781216" name="_main" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/main.py" line="296"></frame><frame id="94234068782320" name="wrap_session" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/main.py" line="240"></frame><frame id="140582904662944" name="pytest_cmdline_main" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/main.py" line="289"></frame><frame id="94234090491968" name="_multicall" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/callers.py" line="187"></frame><frame id="140582904656400" name="&lt;lambda&gt;" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="84"></frame><frame id="94234090684240" name="_hookexec" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/manager.py" line="93"></frame><frame id="94234090554848" name="__call__" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/pluggy/hooks.py" line="286"></frame><frame id="94234067792464" name="main" file="/home/mowglie/.pyenv/versions/py3/lib/python3.8/site-packages/_pytest/config/__init__.py" line="157"></frame><frame id="140582986219072" name="&lt;module&gt;" file="/home/mowglie/.pycharm-2020.2.2/plugins/python/helpers/pycharm/_jb_pytest_runner.py" line="43"></frame></thread></xml>
debugger: received >>114 13 pid_12882_id_140583053184448 140582185093536 FRAME
<<
Received command: CMD_GET_FRAME 114 13 pid_12882_id_140583053184448 140582185093536 FRAME
debugger: received >>114 15 pid_12882_id_140583053184448 140582185093536 FRAME
<<
Received command: CMD_GET_FRAME 114 15 pid_12882_id_140583053184448 140582185093536 FRAME
print(t)
debugger: received >>121 17 pid_12882_id_140583053184448 140582185093536 FRAME print(t)@LINE@
<<
Received command: CMD_CONSOLE_EXEC 121 17 pid_12882_id_140583053184448 140582185093536 FRAME print(t)@LINE@

 

 

0

Note that it must have something to do with my python environment, because running the same test with a much simpler pyenv environment (with just python 3.8 and pytest) works fine...

0

By comparing the two logs (with simple env and more complex env), one of the main differences in the log is that for the complex env (where I have numpy, matplotlib, etc, installed), the log contains a section about `=== Scientific View debug enabled ===` which is not there for the simple one. Could that be the reason?

0

Fabien Maussion

Have you tried recreating the problematic interpreter and environment?

0

Andrey Resler thanks - fater some tries I have been able to isolate the pytest plugin which would cause the error. Now I have to understand what exactly in this plugin is causing problems in pycharm - I wonder if it's something with multiprocessing... I will see if I can test more.

0

Andrey Resler sorry for letting lingering this for so long. The problem persists: the debugger console or variable display hangs when at the breakpoing, although the tests are running fine without debugger. I can't find an easy way to reproduce this, but it seems that certain things we are doing in our code is disturbing PyCharm.

Setting PYDEVD_USE_CYTHON=NO and PYDEVD_USE_FRAME_EVAL=NO does not help.

Here are the two full logs with debug mode on: https://gist.github.com/fmaussion/9406aebb561bb9aa5cf02ebc435b0432

The relevant parts in the logs happen AFTER the tests start, because as I said the problem occurs only if I run some code of ours. And when I run our code, PYCHARM takes new decisions, such as:

 

```

=== Scientific View debug enabled ===

```

Then, later:

 

```

("The debugger thread 'DispatchReader' is traced which may lead to debugging performance issues.",)

```

What could be the reason for these changes? Debugging this problem is slowly driving me crazy...

 

 

 

 

 

0

FWIW: going back to 2019.3.5 did NOT work for me, but going back to 2019.1.4 did. Will stick to that version for the time being...

0

Fabien Maussion Hi, 

Earlier you said that you were able to isolate the issue to Pytest plugin. Do you mean this plugin by any chance?: https://plugins.jetbrains.com/plugin/10242-pytest

Does the issue reproduce if you disable the plugin?

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Andrey Resler No, I'm not using any plugin on the PyCharm side. I was using a custom pytest plugin (which I disabled now) and at least debugging now works in dummy projects. However, debugging on my project still does not work with  current Pycharm (but it does with Pycharm 2019.1.4 which I'm using at the moment).

As I said, it was very difficult for me to isolate the code section which would brake PyCharm's debugger: what I'm doing is importing a module, which at import does a number of things, such as setting up a logger, opening and closing files, importing many packages of scientific python... And after all these lines of code are executed, PyCharms debugger is confused as visible in the logs I provided...

0

Andrey Resler I believe I have the same issue as Fabien.

I am running a pytest debug config. If I set break points in the `test.py` script or in the function imported into `test.py`, debugging works correctly and variables load. If I set the breakpoint inside a class imported from outside the project (in site-packages), the variables never load.

Adding these to the env variables didn't help.

PYDEVD_USE_CYTHON=NO
PYDEVD_USE_FRAME_EVAL=NO

I uploaded two logs, one where the bp is within the project and everything works. One where the bp is external and debug fails.

2020_10_28_SdUe6xDGXLqCt5S8 

0

>If I set the breakpoint inside a class imported from outside the project (in site-packages), the variables never load

Please make sure that you allow stepping into library code in **Preferences | Build, Execution, Deployment | Debugger | Stepping** settings.

If that doesn't help, is it possible to provide sample project and steps to reproduce the issue?

0

Andrey Resler after several months working with the PRO version of pycharm-2019.1.4 (where it doesn't have this issue), I just gave it a try with latest PRO (20.2.5), but the problem is still there.

I'm still very willing to get this fixed (mostly because 2019.1.4 doesn't have py3.8 support) - if my log reports above do not help, maybe I can try to provide a docker container where the bug happens? Would you be willing to run such a container?

0

OK so while trying to run in a docker image with a very similar environment, it turns out it works. While trying to find out what the differences are between the two runs in debug mode, I found one difference at the very beginning of the log:

This is a run that works:

This is a run that doesn't:

The main difference is the "pydev debugger: process ..... is connecting". Could that lead to anything?

0

The first screenshot is running python from Docker container it seems, while the second is a local python from conda env. Regardless, bot say that they have connected to pydev debugger.

>maybe I can try to provide a docker container where the bug happens?

Any project sample/container/steps to reproduce the issue would be helpful in identifying the bug. I would gladly test it if the issue can be reliably reproduced. It is best to create an issue in our bug tracker at https://youtrack.jetbrains.com/issues/py and post all the information necessary to reproduce the issue there. Please ping me in a comment.

0

Andrey Resler I *think* I have nailed it down to multiprocessing, although it does not explain why it sometimes work (e.g. in a container) and sometimes not. Pycharm should be able to stop a programs execution when a breakpoint is set within a function which will run in a multiprocessing pool, right?

0

Andrey Resler I finally managed to produce a clean bug report: https://youtrack.jetbrains.com/issue/PY-46618

Let's continue the discussion on the issue tracker.

1

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