type mockRand … func (mr *mockRand) uint32() uint32 { … } func (mr *mockRand) intn(n int) int { … } func (mr *mockRand) uint32n(n uint32) uint32 { … } func (mr *mockRand) exp2() int { … } func (mr *mockRand) bool() bool { … } func (mr *mockRand) save(*uint64, *uint64) { … } func (mr *mockRand) restore(uint64, uint64) { … } func TestByteSliceMutators(t *testing.T) { … }