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QualityC#

Derive Tests

by teklabsdigital

Derive the fidelity ledger and acceptance scenarios from a locked prototype after gate 2b. Use only when a portion is newly locked or re-locked, never before.

12 stars1 forksAdded 2026/07/16
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Documentation

README

X2 Derive Tests

Turn the locked portion into its tests. Nothing here is authored from imagination: the locked prototype is the acceptance contract, and the tests are projections of it.

What derives from the lock

  • The per-slice fidelity ledger (design/ledger/slice-NNN.md): the locked portion's visual atoms, enumerated. The kernel tests it in both directions: every ledger atom renders (exhaustiveness) and nothing renders beyond the ledger (de-fabrication). Until the prototype-to-ledger exporter exists (owed on the claim), the hand-derived ledger is a known second-source risk: derive it at lock time only, from the artifact on disk, never maintain it by hand alongside a moving prototype.
  • The acceptance scenarios on the e2e floor: the flows the locked portion shows, driven through the real client services against a running server.

The scoping of "no hand-authored test cases"

The ban is precise, per the record's wording fix:

  • Banned: authoring prototype-fidelity tests ahead of the lock. They derive from it.
  • Not banned: claim-driven tests: harness scenarios, gate tests, guard tests. These keep the write-it-first, watch-it-fail shape, and they did the most catching in the pilot.

Coverage expectations the exit report will check

Derivation should leave these satisfiable, because slice-exit reports them:

  • Every public method of every client data service has at least one harness scenario through the real transport, and when the product owns identity, the harness exercises the real sign-in path at least once; minting around auth is setup for other scenarios, never a substitute (INV-10, ruled: the gated harness profile makes this achievable).
  • A composed-app smoke exists per primary flow: the actual entrypoint, at least one real request (INV-07).
  • A service method with no surface in the locked portion is a sanctioned UI-unsurfaced state when it is e2e-covered and its boundary is documented (CONF-03). It is never resolved by inventing UI the prototype does not contain; the fidelity tests would fail that fabrication, and they should.

One discipline line

Prove a derived suite can fail: write one assertion wrong, watch it fail, fix it. A suite that cannot fail is not evidence.

Human-turn contract

  • No gate of its own. A gap between the locked portion and what is derivable is a record-gap question for the human, never an invented criterion.

What this skill must NOT produce

  • Nothing before the lock is on record.
  • No criteria the prototype does not show, no edits to the prototype or ledger direction, no implementation code.

Next

implement.