Python: create temporary files and directories in unittest - Adam Johnson
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Sometimes, tests need temporary files or directories. You can do this in Python’s unittest with the standard library tempfile module. Let’s look at some recipes to do so within individual tests and setUp().
  • logging_strict
    1·
    1 day ago

    why use unittest?

    Besides showing off what a degenerate can accomplish.

    I can run groupings or part of a grouping of unittest testcases in parallel. From a GUI. By typing ~6-10 keystrokes.

    Just never got around to implementing this using pytest. And cuz of that, never published the GUI package.

    Search algorithms matter

    When humans read ^^ nothing registers in the brain. Could write it 1000x and would always fall on closed brains.

    People would still go back to recommending their favorite File Managers (has no search algo) or managing their contacts within each social media platform. And infinite scroll new feeds.

    Without thinking twice about it.

  • logging_strict
    1·
    1 day ago

    Use both unittest and pytest. To get proficient in both.

    Was initially thinking this article is going to turn out to be useless. Then it taught a useful trick that wasn’t aware of.

    Learning something new with unittest is unusual.

    • monomon
      2·
      3 days ago

      This. We kinda stumbled on this pattern, and use it to great effect. Simplified code:

      @pytest.fixture
def tmpfiles():
    with NamedTemporaryFile(suffix=".html") as f:
        yield f

# or for paths, which are more suitable for certain tests
# touch them so they exist
@pytest.fixture
def othertmppaths() -> list[Path]:
    f1 = Path("...")
    f1.touch()
    f2 = Path("...")
    f2.touch()

    yield [f1, f2]
    # you could delete them here if needed
    f1.unlink()

def test_foo(othertmppaths list[Path]):
    result = upload_resource(othertmppaths[0]) 
    assert result.status == 200

      The context manager one will properly clean up all files.

      E: Pretty website btw

      • logging_strict
        1·
        1 day ago

        Often using pytest to debug code. When using a tmp_path, would prefer not to delete the file tree in the end.

        When the test fails, can run the code against the folder tree

        • cd into the tmp folder
        • activate the venv
        • run the code