EntityLookupService

Service for looking up entities by ID with lazy indexing and caching.

Extracted from AbstractClassCheck to enable reuse without inheritance.

The index is cached per storage object, shared across every instance of this service. That matters because ValidatorTestBase constructs a fresh check — and therefore a fresh service — for every data-provider row, so an instance-level index was rebuilt and thrown away once per test case: a full linear scan of the storage (thousands of entities) per lookup. Sharing is safe because the index is a pure function of the storage contents.

A WeakMap keyed on the storage object is used rather than spl_object_id(): object ids are reused once an object is freed, so an id-keyed cache could hand back the index of an unrelated storage that happened to reuse the id. WeakMap entries also disappear with the storage, so nothing is retained after a test's mock storage goes out of scope.

Caveat: the index snapshots the storage the first time a kind is queried. Storages are read-only during validation, so this holds; a caller that mutates a storage after a lookup must call clearIndexCache().