using pytest_configure hook prevents pytest --help from functioning at all

[alexander-lazaris-sonder]

Using pytest 8.3.5

STR

1. add a conftest.py
2. within, add the following

def pytest_configure(config):
    print (config.getoption(""))

3. run pytest --help

At this point, the standard help printout is not triggered. Instead, the code within pytest_configure is run. This is strange to me, as currently I have to remove my pytest_configure code to print any help tips for pytest.

Any tips for having both a pytest_configure hook and the ability to print standard pytest help?

[portyu9]

Hi @alexander-lazaris-sonder

pytest_configure is expected to run during pytest startup even when you invoke:

pytest --help

The problem in the example is this line:

config.getoption("")

getoption() expects the name/destination of a registered command-line option. An empty string is not a valid registered option, so your hook raises during configuration before pytest gets a chance to finish displaying its normal help.

If this is for a custom option, register it first:

def pytest_addoption(parser):
    parser.addoption(
        "--my-option",
        action="store",
        default=None,
        help="My custom option",
    )


def pytest_configure(config):
    value = config.getoption("--my-option")

    if value is not None:
        # configure whatever depends on the option
        ...

Then:

pytest --help

can include your option in the help output without the configuration hook failing.

More generally, pytest_configure should tolerate startup modes where your option has not been supplied. If the configuration is only needed when the option has a meaningful value, guard that work accordingly.

So I would not try to prevent pytest_configure from executing for --help; fix the hook so it remains valid during a help/configuration invocation.

Please mark this answer as accepted if it helped, thank you.