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|
package collection
import (
"testing"
)
func TestLinkedList_findLast_empty(t *testing.T) {
if result := findLast[int](nil); result != nil {
t.Logf("got: %v\nwant: %v", result, nil)
}
}
func TestLinkedList_merge(t *testing.T) {
testCases := []struct {
Left *LinkedList[int]
Right *LinkedList[int]
Expected []int
Comp Comparator[int]
}{
{
NewLinkedList[int](1, 3, 5),
NewLinkedList[int](2, 4),
[]int{1, 2, 3, 4, 5},
UncheckedComparatori,
},
{
NewLinkedList[int](1, 2, 3),
NewLinkedList[int](),
[]int{1, 2, 3},
UncheckedComparatori,
},
{
NewLinkedList[int](),
NewLinkedList[int](1, 2, 3),
[]int{1, 2, 3},
UncheckedComparatori,
},
{
NewLinkedList[int](),
NewLinkedList[int](),
[]int{},
UncheckedComparatori,
},
{
NewLinkedList[int](1),
NewLinkedList[int](1),
[]int{1, 1},
UncheckedComparatori,
},
{
NewLinkedList(2),
NewLinkedList(1),
[]int{1, 2},
UncheckedComparatori,
},
{
NewLinkedList(3),
NewLinkedList[int](),
[]int{3},
UncheckedComparatori,
},
{
NewLinkedList[int](),
NewLinkedList(10),
[]int{10},
UncheckedComparatori,
},
}
for _, tc := range testCases {
t.Run("", func(t *testing.T) {
result, err := merge(tc.Left.first, tc.Right.first, tc.Comp)
if err != nil {
t.Error(err)
}
i := 0
for cursor := result; cursor != nil; cursor, i = cursor.next, i+1 {
if cursor.payload != tc.Expected[i] {
t.Logf("got: %d want: %d", cursor.payload, tc.Expected[i])
t.Fail()
}
}
if expectedLength := len(tc.Expected); i != expectedLength {
t.Logf("Unexpected length:\n\tgot: %d\n\twant: %d", i, expectedLength)
t.Fail()
}
})
}
}
func UncheckedComparatori(a, b int) (int, error) {
return a - b, nil
}
func TestLinkedList_RemoveBack_single(t *testing.T) {
subject := NewLinkedList(1)
subject.RemoveBack()
if subject.Length() != 0 {
t.Fail()
}
}
func TestLinkedList_split_Even(t *testing.T) {
subject := NewLinkedList(1, 2, 3, 4)
left, right := split(subject.first)
if left == nil {
t.Logf("unexpected nil value for left")
t.Fail()
} else if left.payload != 1 {
t.Logf("got: %d\nwant: %d", left.payload, 1)
t.Fail()
}
if right == nil {
t.Logf("unexpected nil for right")
t.Fail()
} else if right.payload != 3 {
t.Logf("got: %d\nwant: %d", right.payload, 3)
}
}
func TestLinkedList_split_Odd(t *testing.T) {
subject := NewLinkedList(1, 2, 3, 4, 5)
left, right := split(subject.first)
if left == nil {
t.Logf("unexpected nil value for left")
t.Fail()
} else if left.payload != 1 {
t.Logf("got: %d\n want: %d", left.payload, 1)
t.Fail()
} else if last := findLast(left).payload; last != 2 {
t.Logf("got:\n%d\nwant:\n%d", last, 2)
t.Fail()
}
if right == nil {
t.Logf("unexpected nil value for right")
t.Fail()
} else if right.payload != 3 {
t.Logf("got:\n%d\nwant:\n%d", right.payload, 3)
t.Fail()
} else if last := findLast(right).payload; last != 5 {
t.Logf("got:\n%d\nwant:%d", last, 5)
}
}
func TestLinkedList_split_Empty(t *testing.T) {
subject := NewLinkedList[*int]()
left, right := split(subject.first)
if left != nil {
t.Logf("got: %v\nwant: %v", left, nil)
t.Fail()
}
if right != nil {
t.Logf("got: %v\nwant: %v", right, nil)
t.Fail()
}
}
func TestLinkedList_split_Single(t *testing.T) {
subject := NewLinkedList(1)
left, right := split(subject.first)
if left == nil {
t.Logf("unexpected nil value for left")
t.Fail()
} else if left.payload != 1 {
t.Logf("got: %d\nwant: %d", left.payload, 1)
t.Fail()
}
if right != nil {
t.Logf("got: %v\nwant: %v", right, nil)
t.Fail()
}
if last := findLast(left).payload; last != 1 {
t.Logf("got:\n%d\nwant:\n%d", last, 1)
t.Fail()
}
}
func TestLinkedList_split_Double(t *testing.T) {
subject := NewLinkedList(1, 2)
left, right := split(subject.first)
if left == nil {
t.Logf("unexpected nil value for left")
t.Fail()
} else if left.payload != 1 {
t.Logf("got: %d\nwant: %d", left.payload, 1)
}
if right == nil {
t.Logf("unexpected nil value for right")
t.Fail()
} else if right.payload != 2 {
t.Logf("got: %d\nwant: %d", right.payload, 2)
}
}
func TestLinkedList_Swap_OutOfBounds(t *testing.T) {
subject := NewLinkedList(2, 3)
if err := subject.Swap(0, 8); err == nil {
t.Log("swap should have failed on y")
t.Fail()
}
if err := subject.Swap(11, 1); err == nil {
t.Logf("swap shoud have failed on x")
t.Fail()
}
if count := subject.Length(); count != 2 {
t.Logf("got: %d\nwant: %d", count, 2)
t.Fail()
}
wantStr := "[2 3]"
gotStr := subject.String()
if wantStr != gotStr {
t.Logf("got: %s\nwant: %s", gotStr, wantStr)
t.Fail()
}
}
func TestLinkedList_Get_OutsideBounds(t *testing.T) {
subject := NewLinkedList(2, 3, 5, 8, 13, 21)
result, ok := subject.Get(10)
if !(result == 0 && ok == false) {
t.Logf("got: %v %v\nwant: %v %v", result, ok, nil, false)
t.Fail()
}
}
func TestLinkedList_removeNode(t *testing.T) {
removeHead := func(t *testing.T) {
subject := NewLinkedList(1, 2, 3)
subject.removeNode(subject.first)
if subject.length != 2 {
t.Logf("got %d, want %d", subject.length, 2)
t.Fail()
}
if first, ok := subject.Get(0); ok {
if first != 2 {
t.Logf("got %d, want %d", first, 2)
t.Fail()
}
} else {
t.Logf("no item at position 0!")
t.Fail()
}
if second, ok := subject.Get(1); ok {
if second != 3 {
t.Logf("got %d, want %d", second, 3)
t.Fail()
}
} else {
t.Logf("no item at position 1!")
t.Fail()
}
}
removeTail := func(t *testing.T) {
subject := NewLinkedList(1, 2, 3)
subject.removeNode(subject.last)
if subject.length != 2 {
t.Logf("got %d, want %d", subject.length, 2)
t.Fail()
}
if first, ok := subject.Get(0); ok {
if first != 1 {
t.Logf("got %d, want %d", first, 1)
t.Fail()
}
} else {
t.Logf("no item at position 0!")
t.Fail()
}
if second, ok := subject.Get(1); ok {
if second != 2 {
t.Logf("got %d, want %d", second, 2)
t.Fail()
}
} else {
t.Logf("no item at position 1!")
t.Fail()
}
}
removeMiddle := func(t *testing.T) {
subject := NewLinkedList(1, 2, 3)
subject.removeNode(subject.first.next)
if subject.length != 2 {
t.Logf("got %d, want %d", subject.length, 2)
t.Fail()
}
if first, ok := subject.Get(0); ok {
if first != 1 {
t.Logf("got %d, want %d", first, 1)
t.Fail()
}
} else {
t.Logf("no item at position 0!")
t.Fail()
}
if second, ok := subject.Get(1); ok {
if second != 3 {
t.Logf("got %d, want %d", second, 3)
t.Fail()
}
} else {
t.Logf("no item at position 1!")
t.Fail()
}
}
t.Run("RemoveHead", removeHead)
t.Run("RemoveTail", removeTail)
t.Run("RemoveMiddle", removeMiddle)
}
|
