schemas.py becomes pydantic, so the reference domain is the normal pattern
rather than an exception carrying a footnote. Frozen: a result is a statement
about what was found, and nothing downstream should edit the finding on its way
to being reported. pydantic stays off the --help path — test_lazy_domains still
passes, which is precisely the assertion that it loads with the domain and not
with the CLI.
The acceptance criterion could not be met as written, and that is the finding
worth keeping. It asked for byte-for-byte parity with the old script; D-263 was
amended after this ticket to give reach a streaming model that puts the verdict
on stderr, while the old script writes its success line to stdout. Measured:
the text is byte-identical in text mode, only the stream differs. Matching both
would mean abandoning streaming or special-casing every ported gate.
So parity is redefined, and it is stronger than bytes where it counts: exit
codes match exactly, no fact the old message carried is lost, and failures name
a remedy as a structured field. That governs every port in T-1251, not just
this one, so it is in D-263 rather than only here.
test_check_parity.py runs three paths — ok, drift, missing file — through both
implementations and compares. It builds a throwaway fixture repo and copies the
OLD script into it, because that script resolves its root from __file__ and has
no override; the new command just takes SR_REPO_ROOT. That asymmetry is part of
why the port earns its keep. It also asserts the failing paths actually exit
non-zero, without which "the exit codes matched" would be vacuous for two
checks that both silently pass.
Proven to fail twice before being trusted. Once by accident: the first version
asserted the yaml version appears on every failing path, which the old script
does not report when the client file is missing — the test was wrong, not the
code, and it now derives expected facts from what the old output actually
contains. Once on purpose: mutating the router to drop a version made it fail
and name the missing fact.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
`reach --help` renders from a declaration table and imports nothing. The cost
of help is now flat as the registry grows, which is the property that has to
hold going from one domain to a dozen.
The trap is real and was confirmed in typer's vendored source rather than
assumed from upstream Click: TyperGroup.format_commands loops over
list_commands calling get_command on each, purely to read a short help string
off the loaded command. With lazy loading underneath, that imports every
domain in the registry to render --help — while the output looks entirely
correct. Nothing observable changes; only the import graph does.
So the test asserts on sys.modules, and it was proven to fail before being
trusted. Disabling the format_commands override made it fail and name the
cause, listing all five leaked check modules. It also carries a positive
control — invoking a domain must import its service — because without one,
"nothing was imported" would pass equally for a loader that is simply broken,
and it fails on an empty registry, which would otherwise satisfy everything
vacuously.
The check domain is created here because the test needs a subject: a stub
raising NotImplementedError would have been committed dead code. That takes
the port out of T-1262, which is rescoped to what it still owns — pydantic
schemas, byte-for-byte output parity on the drift path, and the failure
tests. The old tooling/check-client-version script stays in place and stays
wired to the pre-push hook; the deprecation window is deliberate.
One Typer behaviour worth knowing before every future domain: a single-command
app collapses into a bare command, so `reach check client-version` failed with
"unexpected extra argument" until the router got a callback. Same mechanism as
the root callback, different symptom.
Help now works at every level, closing item 5 of T-1248.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
jpmschweitzerandClaude Opus 5