Pytest capsys
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Testing print/log statements in pytest can be a bit tricky, capsys makes it super easy, but I often struggle to find it.

Date: April 5, 2021

Testing print/log statements in pytest can be a bit tricky, capsys makes it super easy, but I often struggle to find it.

capsys
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capsys is a builtin pytest fixture that can be passed into any test to capture stdin/stdout. For a more comprehensive description check out the docs on capsys <https://docs.pytest.org/en/stable/capture.html#accessing-captured-output-from-a-test-function>

using capsys
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Simply create a test function that accepts capsys as an argument and pytest will give you a capsys opject.

[code]
  def test_print(capsys):
      print('hello')
      captured = capsys.readouterr()
      assert 'hello' in captured.out
      print('world')
      captured = capsys.readouterr()
      assert 'world' in captured.out