}
			permutations = [][]int{p}
		}
		for _, permutation := range permutations {
			name := tc.name + fmt.Sprintf(" permutation %v", permutation)
			t.Run(name, func(t *testing.T) {
				multimap := NewBiMultimap()
				for i := range permutation {
					tc.ops[i](multimap)
					// Run consistency check after every operation.
					err := consistencyCheck(multimap)
					if err != nil {
						t.Fatalf(err.Error())
					}