Enable print_blob for CIs, disable for local

[hugovk]

Fixes #2451.

For #2510.

[Zac-HD]

Hey @hugovk! Please:

• add yourself to the alphabetical list of authors in CONTRIBUTING.rst
• add a RELEASE.rst file - check the other PRs for examples.
• add show_default=False for the setting, and explain in the docstring that the default is True in CI or False in local development

(and thanks for the PR, of course 😍)

[hugovk]

Updated!

And btw I checked for an undocumented CI env var in Azure Pipelines, but not found. Maybe they'll add it one day: GitHub Actions only recently added CI (python-pillow/Pillow#4562).

AP env var docs: https://docs.microsoft.com/en-us/azure/devops/pipelines/build/variables?view=azure-devops&tabs=yaml

[hugovk]

Ha, I must have hit a special small window: I added RELEASE.rst when there was one in master, then fixed the conflict, but I guess the release bot deletes that so got a conflict again!

Rebased!

[Zac-HD]

• rebase on master (so you're creating a minor release file)
• specify in the docstring exactly how the detection works ("True if the X or Y env vars are set, False otherwise", and use Sphinx's envvar role for bonus points)
• look at the failing tests and change the assertions to account for is_in_ci().

And then I think we'll be done!

[hugovk]

• specify in the docstring exactly how the detection works ("True if the X or Y env vars are set, False otherwise", and use Sphinx's envvar role for bonus points)

By docstring, do you mean in description= of settings._define_setting, or to add a proper """...""" one to is_in_ci()?

[Zac-HD]

The value of the description argument, which is eventually formatted into a docstring and rendered in our public docs. Sorry for any confusion!

[hugovk]

Okay! How's that?

• look at the failing tests and change the assertions to account for is_in_ci().

Hmm, do we want those tests to call is_in_ci() to decide what to expect? If so, should we move is_in_ci() to some utility file?

[Zac-HD]

Yes, but let's leave it in _settings.py near its only use in the non-test code.

[Zac-HD]

Hmm. Looking at the actual change, I think it's actually going to be cleaner if we just add print_blob=False to the settings decorator on those inner test functions (or add the decorator too, in one case). Sorry I didn't pick this up before - I think we're otherwise ready to merge!

[hugovk]

The docs build complains about:

/home/vsts/work/1/s/hypothesis-python/docs/../src/hypothesis/__init__.py:docstring of hypothesis.settings.print_blob:1: WARNING: 'envvar' reference target not found: CI
/home/vsts/work/1/s/hypothesis-python/docs/../src/hypothesis/__init__.py:docstring of hypothesis.settings.print_blob:1: WARNING: 'envvar' reference target not found: TF_BUILD

https://dev.azure.com/HypothesisWorks/Hypothesis/_build/results?buildId=4110&view=logs&j=6fe85d43-0322-5a7e-7a5c-a08b11a8fdaa&t=7b5ce327-7af2-52df-14b0-47f2945e41c0

[Zac-HD]

🎉