Implementations and Coverage

Implementation blocks map source paths to component shapes.

Implementation coverage diagram showing source paths mapped through implementation blocks to components, with changed files passing through a coverage gate via Shape update or attestation.

module audit

resource AuditEvent : AppendOnly

component AuditStore {
  owns AuditEvent
}

implementation AuditStoreImpl {
  paths {
    "src/audit/**/*.ts"
  }
  conforms_to AuditStore
  on_change require shape_update
}

The coverage command compares changed files with these governed paths. A matching source or evidence reference only counts when the declaring .shape file is part of the current changed-file list.

Missing model update failure

Run:

shp coverage --changed-files fixtures/changed/audit_purge.txt fixtures/fail/missing_shape_update/audit.shape

If src/audit/purge.ts is governed by AuditStoreImpl and the change set does not include a Shape update or current attestation, coverage fails.

Why coverage is separate

Conformance checks answer: “Is this model coherent?”

Coverage checks answer: “Did this change set update the model when governed source changed?”

Both checks matter. A coherent Shape model can still miss a required current global model update.