tier1 conftest applies `integration` marker to every collected test, not just tier1

[mlieberman85]

Summary

tests/darnit/parity/tier1/conftest.py:32 implements pytest_collection_modifyitems intending to mark every parity-tier1 test as integration (per PR #370 review fix). The implementation iterates the ENTIRE items collection pytest passes in, not just items under the conftest's own scope:

def pytest_collection_modifyitems(config: pytest.Config, items: list) -> None:
    integration_mark = pytest.mark.integration
    for item in items:
        item.add_marker(integration_mark)

As a result, when pytest runs the full test tree (e.g., CI's pytest tests/ -m integration), every collected test in the workspace gets the integration marker applied by this hook -- including tests that the author never intended to mark.

Symptom

PR #384's CI failure (2026-08-23) was a real example: tests/darnit/context/test_dot_project_upstream.py::TestUpstreamSpecSync::test_upstream_spec_unchanged is a @pytest.mark.upstream-only canary (docstring: "It does NOT block PRs -- it's informational to alert maintainers when the upstream spec evolves"). CI's -m integration step should NOT have collected it. But it did, because tier1's hook globally added integration, and #384 got blocked on unrelated CNCF spec drift until #386 landed the reconcile.

The tier2 conftest at tests/darnit/parity/tier2/conftest.py:15 has the same over-broad iteration and needs the same fix.

Fix

Constrain each hook to items under its own conftest's directory:

CONFTEST_DIR = Path(__file__).parent

def pytest_collection_modifyitems(config: pytest.Config, items: list) -> None:
    integration_mark = pytest.mark.integration
    for item in items:
        try:
            item_path = Path(str(item.fspath))
        except Exception:
            continue
        if CONFTEST_DIR in item_path.parents or item_path == CONFTEST_DIR:
            item.add_marker(integration_mark)

Same shape applied to tier2's conftest.

Regression guard

Add a test that runs pytest tests/darnit/context/test_dot_project_upstream.py -m integration --collect-only and asserts zero tests are collected. That would have caught this class of leak.

Related

• CNCF .project/ spec drift: repositories items now RepositoryEntry objects #385 (side note documented at file time; no fix landed there).
• Feature 028 (parity Tier 1) / feature 029 (Tier 2) -- code owners.
• PR feat(baseline): ruleset-aware branch-protection verdict (closes #343) #384 (real-world instance where the leak surfaced).