docs: Makefile: Add a testdocs target for the documentation unit tests

tools/unittests/run.py discovers and runs the unit tests there (which
are primarily documentation tools), but nothing in the build calls it,
so the tests are only run by whoever remembers that the script is there.

Give it a target, next to the other checks that need no Sphinx. The name
ends in "docs", so it matches the "%docs" pattern already in
no-dot-config-targets and runs without a configured tree, and it sets
PYTHONPYCACHEPREFIX as the other Python targets here do, to keep
__pycache__ directories out of the source tree.

  $ make testdocs
  ...
  Ran 121 tests

with "make dochelp" listing it between refcheckdocs and cleandocs.

Tested with GNU Make 4.4.1 and Python 3.14.7, on a tree with no .config,
where it ran 121 tests and left no __pycache__ behind.

Assisted-by: LLM
Signed-off-by: Kees Cook <kees@kernel.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Nicolas Schier <n.schier@fritz.com>
Reviewed-by: Nicolas Schier <n.schier@fritz.com>
Reviewed-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260916184107.i.183-kees@kernel.org>

0 files changed, 0 insertions, 0 deletions