Fix lockfile metadata serialization order#29
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laulauland merged 4 commits intomainfrom May 5, 2026
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Wire minish v0.3.0 into the build as a test-only module. Seed defaults to the first 16 hex chars of the current git HEAD so each commit explores a fresh slice of the state space; override with -Dminish-seed=<u64> to reproduce a specific failing run. Plumbed through helpers.minish_seed so property tests share one source of truth. Smoke test runs 25 iterations of a trivial int property to catch regressions in the wiring (import, module shape, seed plumbing). DRIFT-mshkigwb
Bindings were serialized with metadata fields in insertion order (per `Binding.setField` at lockfile.zig:33-45), which meant two branches that converged on the same semantic state through different `setField` sequences produced different byte strings for the same binding — and git/jj flagged those as spurious textual merge conflicts. Sort metadata by key in `renderLineToWriter` so the on-disk form is a function of semantic state only. The sort buffer reuses the `scratch` allocator that `serializeToWriter` already threads through, so no new lifetime surface. Unblocks the upcoming serialization-under-reorder property test. DRIFT-hoocxemw
…ld reorder Property: semantic_eq(L1, L2) ⟹ serialize(L1) == serialize(L2). The generator builds a lockfile state with up to 6 bindings, each with 0–6 metadata fields drawn uniquely from a fixed key pool; the property builds two `[]Binding` slices from that state (forward order, forward fields vs. reverse order, reverse fields) and asserts byte-equal serialize outputs. Runs 200 iterations, seeded from helpers.minish_seed (git HEAD by default; -Dminish-seed=<u64> to reproduce). Verified that the test catches the insertion-order bug by temporarily reverting the canonicalization fix — property fails with a counterexample showing differing serializations within the first few iterations. DRIFT-zvfkxuyr
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Summary
Fixes a lockfile serialization bug where equivalent metadata could be written in different field orders depending on how the binding was built. That made semantically identical lockfile states produce different bytes, which in turn created avoidable textual merge conflicts.
The fix canonicalizes metadata field order during serialization and adds a property test that reproduces the class of bug: two lockfiles with the same bindings and fields, but different binding/field iteration order, must serialize to byte-identical output.
What changed
minishfor property-based tests — test-only dependency, with deterministic seed support via-Dminish-seed=<u64>.serializenow emits metadata fields sorted by key.serializeis invariant under binding and field reorder.The broader merge-resistance measurements and format experiments have been split out of this PR and kept for follow-up work.
Test plan
zig build test