utils/dep_freshness/versions.py
Krzysztof kuhy Rudnicki 2a2f18ca56 Add the shared dependency-freshness gate
"Are we on the newest version?" was not mechanically answerable across these
repos: constraint styles had drifted per-ecosystem and a caret range is
"newest-compatible" by definition, which gives a checker nothing to compare.
This gate makes it answerable and then enforces the answer.

Checks two things at once -- that every dependency carries an exact pin, and
that the pin equals its registry's latest STABLE release -- across pub.dev,
PyPI, npm, crates.io, the Go proxy, kuhyx/utils git tags, and the Flutter /
Node / Python toolchains.

Three deliberate design points:

* Pre-releases are rejected per-ecosystem, because every ecosystem leaks them
  differently and each leak fails GREEN. npm lets a maintainer point
  `dist-tags.latest` at an rc; crates.io's `max_version` includes them; PyPI's
  legacy `info.version` includes yanked releases. Unit-tested with fixtures,
  since an end-to-end run cannot surface a wrong "up to date".

* Offline, the gate serves an expired cache entry and PASSES with a DEGRADED
  banner (exit 3 only under --strict, which is CI). `--no-verify` is banned
  here, so a hook that hard-failed offline would leave no way to commit at all.

* The allowlist has two entry classes. `blocked_by: transitive:<pkg>@<ver>` is
  a predicate that clears itself when upstream moves and must NOT carry a
  date; everything else is discretionary and requires `expires`, capped at 90
  days. Exact pins plus latest-everywhere is provably unsatisfiable when a
  dependency internally constrains a shared transitive, and expiring the
  predicate class on a calendar would turn the gate red for a reason no commit
  could fix. An entry with nothing left to excuse is itself an error.

One hook id, one shim, one shared implementation -- always delegating, so it
cannot fork the way the 250-line cap forked into four ids, two of which were
independent reimplementations.

256 tests, 100% branch coverage on every module of the gate. Also adds the
workflow that runs them, which incidentally gives md_naming's 71 tests their
first CI run.

Not yet installed in any repo: a repo that gets the gate before its deps are
bumped is instantly and permanently red, so the gate and the upgrade land
together, per repo.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CRykabMwPgDzFHcARoqpaK
2026-08-28 13:00:35 +02:00

93 lines
3.1 KiB
Python

"""Version parsing shared by every ecosystem adapter.
The dangerous bug class here fails *green*: npm publishes pre-releases to
`dist-tags.latest` and crates.io's `max_version` includes them, so an adapter
that trusts either reports "up to date" while the pin is behind. Every
"latest" that leaves this package goes through `newest_stable`.
"""
from __future__ import annotations
import re
from packaging.version import InvalidVersion, Version
# Dart/pub and Go use semver; PyPI uses PEP 440. `packaging` parses both well
# enough to compare, with this as the fallback for the odd Go pseudo-version.
_SEMVER = re.compile(
r"^v?(?P<core>\d+(?:\.\d+){0,2})"
r"(?:-(?P<pre>[0-9A-Za-z.-]+))?"
r"(?:\+(?P<build>[0-9A-Za-z.-]+))?$"
)
def parse(raw: str) -> Version | None:
"""A comparable version, or None when the string is not one."""
text = raw.strip().lstrip("v")
try:
return Version(text)
except InvalidVersion:
match = _SEMVER.match(raw.strip())
if not match:
return None
# `core` is `\d+(\.\d+){0,2}`, which Version always accepts.
return Version(match.group("core"))
def is_prerelease(raw: str) -> bool:
"""True for `1.2.0-beta.1`, `2.0.0rc1`, `1.0.0-dev` and friends.
Checked on the raw string as well as the parsed object because PEP 440
silently normalises some semver pre-release tags (`-alpha` survives, but
an unknown suffix can be dropped) and a dropped suffix reads as stable.
"""
if "-" in raw.split("+", 1)[0].lstrip("v"):
return True
version = parse(raw)
return bool(version and (version.is_prerelease or version.is_devrelease))
def newest_stable(candidates) -> str | None:
"""The highest non-pre-release version in `candidates`, or None."""
best: tuple[Version, str] | None = None
for raw in candidates:
if not raw or is_prerelease(raw):
continue
version = parse(raw)
if version is None:
continue
if best is None or version > best[0]:
best = (version, str(raw).strip().lstrip("v"))
return best[1] if best else None
def behind(pinned: str, latest: str) -> bool:
"""True when `pinned` is strictly older than `latest`.
Unparseable input is never reported as behind: an unpinned or exotic
constraint is a different finding (`UNPINNED`) and must not be dressed up
as staleness.
"""
left, right = parse(pinned), parse(latest)
if left is None or right is None:
return False
return left < right
EXACT = re.compile(r"^\s*(?:==\s*)?v?\d+(?:\.\d+){0,2}(?:[-+][0-9A-Za-z.-]+)?\s*$")
def exact_pin(constraint: str) -> str | None:
"""The version an exact constraint names, or None if it is a range.
`1.6.0` and `==1.6.0` are exact; `^1.6.0`, `>=1.6.0`, `any` and `*` are
not. A range is not comparable to a registry answer, which is the whole
reason Q6 asked for exact pins.
"""
if not constraint:
return None
text = str(constraint).strip()
if not EXACT.match(text):
return None
return text.lstrip("=").strip().lstrip("v")