Go condition coverage and an omitted requirement

Executed teaching fixture recorded on 9 October 2026.
The cache helper intentionally ignores Entry.Deleted. Do not use it as production code.

Prerequisite: Go 1.22 or later. No third-party Go modules are needed.
Recorded environment and source SHA-256 values are in evidence/provenance.json.

From the extracted directory:
  go test -count=1 -v ./cache
Expected: the A, B, C and D independence cases pass.

  go test -count=1 -tags requirement -run TestTombstoneIsNotServed -v ./cache
Expected: FAIL, exit code 1, "a deleted entry must not be served".
This is the deliberately missing obligation. Do not treat the exit code as a setup failure.

If you already have access to the Proof CLI:
  proof mcdc measure ./cache --engine go --format json
The recorded run used proof 0.1.0-dev+geeb5981c.
The recorded report has one decision, three covered conditions and four samples.
Inspect skipped conditions as well as the witness pairs. The Deleted field is absent
from the measured predicate, so coverage cannot establish its requirement.

This download contains the example and recorded evidence, not the Proof CLI.
The Go tests run without Proof. You can inspect the recorded MC/DC report without it.
The JSON report omits only an ephemeral local coverage profile path; its results are unchanged.
