pytest capsys: checking output AND getting it reported?

Question

Python 3.4.1, pytest 2.6.2.

When a test fails, pytest will routinely report what was printed to stdout by the test. For instance this code:

Answer 1

You're seeing the correct behaviour, when using capsys.readouterr() you're consuming the captured output. Hence any output to stdout and stderr will no longer show up in the test report. But any new output which you create after this and do not consume will still be reported, so you can get the full output back in the report by simply writing it to the output streams once more:

def test_result_and_stdout(capsys):
    result = method_under_test()
    out, err = capsys.readouterr()
    sys.stdout.write(out)
    sys.stderr.write(err)
    assert out.startswith("Hello")
    assert result == 42