Monitor usage resulting in repeated printing

Describe the bug I use captured print statements to build test reports. In using pytest-monitor, I notice that its usage produces the effect of repeating these statements.

To Reproduce Steps to reproduce the behavior:

1. Create a simple hello-world pytest function.
2. Run the test with the -s flag to allow printing to console, observe multiple statements.
3. Run again but include -p no:monitor, observe single statement.

Expected behavior The printing of a single statement.

Screenshots

Desktop (please complete the following information):

• OS: Pop!_OS 20.04LTS
• Python 3.7.8
• Pytest 6.0.2
• Other plugins: metadata, html

[js-dieu]

After some investigations, I think the problem is related to memory_profiler. The following example illustrates the problem you are experiencing:

import memory_profiler

def foo():
   print('Hello World')

if __name__ == '__main__':
   print(memory_profiler.memory_usage((foo, ()), max_usage=True, retval=True))

This prints the following on my machine:

Hello World
Hello World
Hello World
Hello World
Hello World
Hello World
Hello World
(25.5625, None)

If I remove the memory profiling part from the plugin, the output is as expected. I’ll ask for some support to memory_profiler.

Edit: https://github.com/pythonprofilers/memory_profiler/issues/298

[js-dieu]

Hello @csheaff

Thanks for reporting. It is a bit weird to me as I do not play at all with capture fixtures nor the way pytest handles logs and prints. I might be hard to analyze and debug but I’ll try to have a look this week prior to the upcoming release of pytest-monitor.