How to make pytest fail if print exists?

Question

How can I make pytest fail if there is a print statement in the code?

Also (for security it can be useful), it will be great if the print does not actually get executed or shown in the CI.

Do you mean semantic print statements in code, or stdout/stderr output, the first is solved with parsing, the latter by collecting output from subprocess. — MortenB, Nov 17 '20 at 09:52

alex_noname · Accepted Answer · 2020-11-23T07:56:17.383

2

Try to use session scope autouse fixture for print monkey patching , like so:

@pytest.fixture(scope='session', autouse=True)
def mock_print():
    with mock.patch("builtins.print", side_effect=Exception('Print is not allowed!')) as _fixture:
        yield _fixture

Put this fixture in the conftest.py file, which is located in your test directory. We can define the fixture functions in this file to make them accessible across multiple test files. You can read more about this file here:

In pytest, what is the use of conftest.py files?

https://docs.pytest.org/en/2.7.3/fixture.html?highlight=conftest#sharing-a-fixture-across-tests-in-a-module-or-class-session

edited Nov 23 '20 at 07:56

answered Nov 20 '20 at 14:02

alex_noname

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so do I need to add this this decorator on each separate `def test_` ? – Newskooler Nov 21 '20 at 08:57
Just insert it to root conftest file in test directory – alex_noname Nov 21 '20 at 09:08
What is the `root conftest file`? – Newskooler Nov 23 '20 at 07:11

How to make pytest fail if print exists?

1 Answers1