NopCloser wraps a [blob.Store] with a no-op Close method to implement [blob.StoreCloser].

Run applies the test script to empty store s, then closes s.

SubCAS traverses a sequence of zero or more subspace names beginning at s, and returns a CAS for the last name in the sequence.

SubKV traverses a sequence of zero or more subspace names beginning at s, and returns a KV for the last name in the sequence.