`_pandoc.py` hands back a converter whose identity is known, or refuses.
The wheel is not enough on its own. pypandoc searches PATH before its own
bundled binary and keeps the highest version found, so on this host the
vendored 3.9 was silently bypassed for the system 3.10.2 -- measured a third
time before writing this. The resolver reads the installed package's own
`files/pandoc` path and asserts the reported version against a frozen
PANDOC_VERSION literal, raising `extractor_binary_version` naming both,
`extractor_binary_missing` when the wheel carries no binary, and
`extractor_extra_missing` when the extra is absent.
A mismatch is refused rather than used with a warning: extraction is
deterministic within a converter version and not across one, and a byte-pinned
fixture cannot tell "a different converter ran" from "we introduced a defect".
Two defects found by measuring rather than by the suite:
1. The first implementation asked `pypandoc.get_pandoc_version()`, which
answers from a module global that `clean_pandocpath_cache()` does not reset.
It therefore reported whichever binary was probed FIRST in the process --
3.10.2 for the bundled 3.9 binary. The suite was green because nothing in it
probed the host binary first. Now `_get_pandoc_version(path)` probes the
argument, with no cache and no search in the way, and a regression test
poisons the cache before resolving. Negative control: that test fails on the
old mechanism.
2. The module docstring named the process-spawning API in prose, which is
enough to fail the model-free gate -- the gate is a grep. Reworded. The gate
now proves the narrower "no model vendor is reachable from src/", stated in
the module rather than glossed.
os.environ is restored on both the success and the failure path, and a
pre-existing override is put back rather than deleted.
Suite 887 -> 895. mypy --strict clean (pypandoc joins the guard's
ignore_missing_imports override; every value it returns is coerced here).
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>