JUnitXML attachments

[vbennich]

Hi,

According to this post: https://devblogs.microsoft.com/devops/junit-attachments-support-for-publish-test-results/
We can now attach files to test-cases in the junit xml for them to be attached and published in a azure devops pipeline.
If we could implement support for this, I would not need to use the pytest-nunit plugin (which does not work well for reporting Subtests).
Perhaps we could implement a similar fixture as in the pytest-nunit plugin (add_nunit_attachment).
Although i haven't gotten it to work (I think my DevOps instance might not support JUnit attachments yet) I have implemented the following fixture which according to that blog post should work:

@pytest.fixture(scope="session")
def junit_xml_dir(pytestconfig):
    """
    Returns the **directory** where the JUnit XML file will be written.
    """
    junit_path = pytestconfig.getoption("--junitxml")
    if junit_path is None:
        # Fallback if someone runs without --junitxml
        return Path.cwd()

    return Path(junit_path).parent.resolve()

@pytest.fixture
def add_junit_attachment(file: Path, junit_xml_dir: Path):
    yield  # ← test runs here

    if not file_path.is_file():
        continue
    size_bytes = file_path.stat().st_size
    if size_bytes == 0:
        continue
    if size_bytes >= MAX_SIZE_BYTES:
        continue
    relative_path = file_path.relative_to(junit_xml_dir)
    print(f"\n[[ATTACHMENT|{path}]]\n")

I can generate a junit xml that looks like this:

<?xml version="1.0" encoding="utf-8"?><testsuites name="pytest tests"><testsuite name="pytest" errors="0" failures="0" skipped="0" tests="1" time="0.311" timestamp="2026-01-16T12:09:09.372792+01:00" hostname="hostname"><testcase classname="tests.junit.test_attachment" name="test_junit_attachment" time="0.286"><system-out>--------------------------------- Captured Log ---------------------------------
--------------------------------- Captured Out ---------------------------------

[[ATTACHMENT|test_attachment/stdout.log]]

[[ATTACHMENT|test_attachment/other_attachment.txt]]


</system-out><system-err>--------------------------------- Captured Err ---------------------------------

</system-err></testcase></testsuite></testsuites>

[RonnyPfannschmidt]

yikes - they really extended a xml format with a custom cdata format instead of anything sensible using the normal xml extension mechanisms

i'm strictly opposed to have this horrible hack in core - it should be a plugin

[vbennich]

Yes this is ugly af. Probably just gonna go and use pytest-nunit again (which I'd like to be part of core) but that plugin does not report for test cases using subtests if i remember correct.

But if anyone got an attachment to work with junit and Azure DevOps, please let me know 😄