Define and implement property tests for parameter-pack canonicalisation and migration policy (ADR 005)

[coderabbitai]

Background

ADR 005 (PR #9, branch 1-1-4-record-seeded-prng-choice) ratifies a canonicalisation contract for contentHash computation and a semantic-version migration policy for parameter packs, but defers all implementation — including test coverage — to later roadmap items (principally 1.3.2, 1.4.x, and 2.4.3).

A review check flagged that the decision record specifies determinism, canonicalisation, and migration invariants without documenting a property-test strategy. Golden-vector snapshot tests are proposed for the PRNG but no equivalent is proposed for:

• Canonicalisation rules (key ordering, numeric-subset extraction, field exclusion, whitespace normalisation, NaN/Infinity rejection, duplicate-key rejection)
• Migration policy conditions (PATCH rebind predicate, MINOR upgrade eligibility, MAJOR quarantine trigger)

Required work

1. When roadmap item 1.3.2 lands (ParameterPack type and contentHash serialiser): author fast-check property tests that assert:
   • Canonicalisation is stable under arbitrary key-insertion order
   • Numeric-subset extraction is byte-identical for semantically equal numeric values
   • NaN, Infinity, and undefined fields are rejected deterministically
   • Round-trip: canonicalize(pack) === canonicalize(canonicalize(pack))
2. When roadmap item 1.4.x lands (Dexie schema and migration transforms): author property tests that assert:
   • PATCH rebind predicate returns true iff canonical numeric subsets are byte-identical
   • MINOR upgrade prompt is triggered iff MAJOR segment is equal and numeric subsets differ
   • MAJOR quarantine is triggered iff MAJOR segment differs
   • Sequential transform application is order-deterministic

References

• PR Plan seeded PRNG choice and pack migration policy (1.1.4) #9 — Plan seeded PRNG choice and pack migration policy (1.1.4)
• ADR 005: docs/adr-005-use-deterministic-simulation-and-parameter-packs.md
• Roadmap items 1.3.2 and 1.4.x in docs/roadmap.md

Raised by @leynos via code-review check on PR #9.

[coderabbitai]

🔗 Related PRs

leynos/wildside#346 - Add canonical route cache key derivation and tests (5.1.4) [merged]
leynos/actix-v2a#27 - Add SSE property tests (#18) [merged]
leynos/rstest-bdd#493 - Implement first-party harness-led attribute defaults (9.7.2) [merged]
#7 - Record XState machine collocation strategy (1.1.3) [merged]

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