Replace dpkg-checkbuilddeps with a native implementation:
- full dependency grammar: comma clauses, | alternatives, << <= = >= >>
relations, :arch qualifiers (any/native/specific), [arch lists] and
<profile restriction> formulas per alternative;
- restriction reduction against active build profiles and the host arch
at parse time (reduce_restrictions semantics);
- evaluation against a parsed dpkg status database with Multi-Arch
semantics (foreign/allowed) and versioned Provides rules (unversioned
provides never satisfy versioned deps; versioned ones must satisfy the
relation);
- clause simplification with implication-based deduplication, rendering
dpkg-compatible 'unmet build dependencies/conflicts' diagnostics.
check_build_depends() consumes debian/control + CheckOpts (-A/-B/-I
equivalents). run_source_build performs the check when forced (-D
parity); source-only builds skip it entirely like dpkg-buildpackage,
and unsatisfied deps propagate as UnmetBuildDependencies -> exit 3.
Unit tests port the Dpkg_Deps.t reduction matrices; differential gate
runs 24 scenarios (alternatives, versions, arch/profile restrictions,
Multi-Arch, Provides, conflicts, -A/-B flags) against real
dpkg-checkbuilddeps comparing exit status and diagnostics.
Implement the documented dpkg ordering algorithm (Debian Policy 5.6.1):
numeric epoch, then upstream/revision compared as alternating non-digit
and digit chunks, with '~' ordering before anything including the empty
chunk and letters before non-letters in non-digit chunks.
Adds Ord/PartialOrd for DebianVersion, a free compare() and a
later_than() convenience.
Unit tests port all vectors from dpkg's scripts/t/Dpkg_Version.t plus
Ubuntu-flavored cases (security uploads, ~ppa1 backports). Differential
gate: every vector cross-checked against real 'dpkg --compare-versions'
for <<, <=, =, >= and >>.
Embed dpkg's factual cputable/ostable/tupletable/abitable data and
implement tuple/triplet/multiarch lookups, wildcard matching, arch
restriction evaluation and the full DEB_BUILD_*/DEB_HOST_*/DEB_TARGET_*
environment dump natively.
build/env.rs::arch_env now delegates to the native implementation
instead of shelling out to 'dpkg-architecture -f'.
Differential gate (build/mod.rs): arch_env(Some(a)) must equal real
'dpkg-architecture -f -a a' key-for-key for every architecture listed by
'dpkg-architecture -L', plus the native case. Data tables carry upstream
attribution comments; no dpkg code was transliterated.
vhaudiquet