[wic][PATCH v3 02/10] tests: add a session banner via conftest.py

[Trevor Woerner <twoerner@gmail.com>]

When a test run starts it is useful to see, at a glance, exactly what
is being tested: which host the run is on, which Python and pytest are
in use, and -- most importantly -- which wic the suite imported and
what version it reports. Without that, a passing or failing run is
hard to attribute, especially when more than one wic checkout or
virtualenv is in play.

pytest looks for a file named conftest.py and, among other things,
calls its pytest_report_header() hook to print extra lines in the
session header before collection begins. This commit adds that file
with a single hook that prints a short banner:

  - the host node name, operating system, and machine type;
  - the running Python version and the pytest version;
  - the version wic reports and the filesystem path the wic module was
    imported from.

The wic lookup is defensive: if wic cannot be imported (for example
the test extras were not installed, or the suite is being run outside
the checkout) the banner says so rather than aborting the run, so the
failure is visible in the header instead of as an opaque collection
error.

The file name conftest.py is mandatory; pytest discovers it by name,
so it cannot be called anything else.

AI-Generated: codex/claude-opus 4.7 (xhigh)
Signed-off-by: Trevor Woerner <twoerner@gmail.com>
---
changes in v3:
- no change in this revision.
changes in v2:
- v1 submitted the entire test suite as a single commit; v2 breaks
  the work into a reviewable series, and this patch is one step of it.
---
 tests/conftest.py | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 tests/conftest.py

diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 000000000000..1c368ebf8595
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1,38 @@
+# Session banner for the wic test suite.
+#
+# Before collection, print the environment the tests exercise:
+#   - the host
+#   - the Python and pytest versions
+#   - the wic under test (its version and the module path of its import)
+
+import platform
+
+import pytest
+
+
+def _wic_under_test():
+    """Return (version, module_path) for the wic being tested."""
+    try:
+        import wic.cli as wic_cli
+    except Exception as exc:  # pragma: no cover - reported in the banner
+        return ("(import failed: %s)" % exc, "(unimported)")
+    version = getattr(wic_cli, "__version__", "(unknown)")
+    module_path = getattr(wic_cli, "__file__", "(unknown)")
+    return (version, module_path)
+
+
+def _format_banner():
+    wic_version, wic_path = _wic_under_test()
+    lines = [
+        "wic test suite",
+        "  host:   %s  %s %s" % (
+            platform.node(), platform.system(), platform.machine()),
+        "  python: %s   pytest: %s" % (
+            platform.python_version(), pytest.__version__),
+        "  wic:    %s  (%s)" % (wic_version, wic_path),
+    ]
+    return "\n".join(lines)
+
+
+def pytest_report_header(config):
+    return _format_banner()
-- 
2.50.0.173.g8b6f19ccfc3a