for i, cn := range tc.cns {
				if i >= r.len() {
					t.Errorf("missing cert %v @ %v", cn, i)
				} else if r.mustCert(t, i).Subject.CommonName != cn {
					fmt.Printf("%#v\n", r.mustCert(t, 0).Subject)
					t.Errorf("unexpected cert common name %q, want %q", r.mustCert(t, i).Subject.CommonName, cn)
				}
			}
			if r.len() > len(tc.cns) {

	}
	for id, value := range d.sparse {
		if !yield(id, value) {
			return false
		}
	}
	return true
}

// mustGet returns the E for id or panics if it fails.
//
// This should only be used if id has already been validated.
func (d *dataTable[EI, E]) mustGet(id EI) E {
	data, ok := d.get(id)
	if !ok {
		panic(fmt.Sprintf("expected id %d in %T table", id, data))
	}
	return data
}