Turn on print, stderr, or stdout by tag during test run in Behave Python

Question

So I am trying to implement an @warn tag. The idea is this test doesn't make an assertion and fail, but instead simply prints out a warning. I see this answer here, but that only explains how to do it on command line or in Behave.ini file, but I don't want to turn it on for all tests, just ones tagged warn. I tried this in my environment file but with no success:

def before_scenario(context, scenario):
    if 'warn' in context.tags:
        # Set to immediately out rather than keep for fail
        stdout_capture = False
        stderr_capture = False

def after_scenario(context, scenario):
    if 'warn' in context.tags:
        stdout_capture = True
        stderr_capture = True

Answer 1

I think you need to modify the context, not just create a variable with that name. Unfortunately, even context.stdout_capture = sys.__stdout__ doesn't seem to solve this. It generates a ContextMaskWarning as you are modifying something that behave will, and does, overwrite. Of course you could modify your instance behave to avoid this.