func TestIterate(t *testing.T) {
const N = 1000
deque := deque.New()
for i := 0; i < N; i++ {
deque.PushBack(i)
}
// iterate from front to back
i := 0
for e := deque.Front(); e != nil; e = e.Next() {
if e.Value != i {
t.Errorf("got: %d, want: %d", e.Value, i)
}
i++
}
// iterate from back to front
i = N - 1
for e := deque.Back(); e != nil; e = e.Prev() {
if e.Value != i {
t.Errorf("got: %d, want: %d", e.Value, i)
}
i--
}
}
func TestEmpty_iterator(t *testing.T) {
deque := deque.New()
front := deque.Front()
if front != nil {
t.Errorf("got: %v, want: <nil>", front.Value)
}
back := deque.Back()
if back != nil {
t.Errorf("got: %v, want: <nil>", back.Value)
}
}
func BenchmarkIterate_backward(b *testing.B) {
const N = 1024
deque := deque.New()
for i := 0; i < N; i++ {
deque.PushBack(i)
}
b.ResetTimer()
for i := 0; i < b.N; i++ {
for it := deque.Back(); it != nil; it = it.Prev() {
_ = it.Value
}
}
}
func ExampleIterator() {
const N = 10
deque := deque.New()
for i := 0; i < N; i++ {
deque.PushBack(i)
}
// iterate from front to back
for it := deque.Front(); it != nil; it = it.Next() {
fmt.Printf("%v", it.Value)
}
fmt.Println()
// iterate from back to front
for it := deque.Back(); it != nil; it = it.Prev() {
fmt.Printf("%v", it.Value)
}
fmt.Println()
// Output:
// 0123456789
// 9876543210
}