Add list unit testing

internal/list/list_test.go

@@ -0,0 +1,97 @@
+package list
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLruList_lazyInit(t *testing.T) {
+	l := NewList[int, int]()
+	assert.EqualValues(t, 0, l.Length())
+	l.root.next = nil
+	l.root.prev = nil
+
+	first := l.PushFront(1, 11)
+	assert.EqualValues(t, 1, first.Key)
+	assert.EqualValues(t, 11, first.Value)
+	assert.Equal(t, first, l.root.next)
+	assert.EqualValues(t, 1, l.Length())
+
+	second := l.PushFront(2, 22)
+	assert.EqualValues(t, 2, second.Key)
+	assert.EqualValues(t, 22, second.Value)
+	assert.Equal(t, second, l.root.next)
+	assert.Equal(t, first, l.root.next.next)
+	assert.EqualValues(t, 2, l.Length())
+}
+
+func TestLruList_PushFront(t *testing.T) {
+	l := NewList[int, int]()
+	assert.EqualValues(t, 0, l.Length())
+
+	first := l.PushFront(1, 11)
+	assert.EqualValues(t, 1, first.Key)
+	assert.EqualValues(t, 11, first.Value)
+	assert.Equal(t, first, l.root.next)
+	assert.EqualValues(t, 1, l.Length())
+
+	second := l.PushFront(2, 22)
+	assert.Nil(t, second.PrevEntry(), nil) // forbid root
+	assert.Equal(t, first.PrevEntry(), second)
+
+	assert.EqualValues(t, 2, second.Key)
+	assert.EqualValues(t, 22, second.Value)
+	assert.Equal(t, second, l.root.next)
+	assert.Equal(t, first, l.root.next.next)
+	assert.EqualValues(t, 2, l.Length())
+}
+
+func TestLruList_Remove(t *testing.T) {
+	l := NewList[int, int]()
+	first := l.PushFront(1, 11)
+	second := l.PushFront(2, 22)
+
+	removed := l.Remove(first)
+	assert.EqualValues(t, 11, removed)
+	assert.Equal(t, second, l.root.next)
+
+	removed = l.Remove(second)
+	assert.EqualValues(t, 22, removed)
+	assert.Equal(t, &l.root, l.root.next)
+	assert.Equal(t, &l.root, l.root.prev)
+}
+
+func TestLruList_Back(t *testing.T) {
+	l := NewList[int, int]()
+	assert.Nil(t, l.Back())
+
+	first := l.PushFront(1, 11)
+	_ = l.PushFront(2, 22)
+	assert.Equal(t, first, l.Back())
+}
+
+func TestLruList_MoveToFront(t *testing.T) {
+	t.Run("move root", func(t *testing.T) {
+		l := NewList[int, int]()
+
+		first := l.PushFront(1, 11)
+		second := l.PushFront(2, 22)
+		l.move(&l.root, &l.root)
+		assert.Equal(t, second, l.root.next)
+		assert.Equal(t, first, l.root.next.next)
+	})
+	t.Run("move entry", func(t *testing.T) {
+		l := NewList[int, int]()
+
+		first := l.PushFront(1, 11)
+		second := l.PushFront(2, 22)
+		assert.Equal(t, second, l.root.next)
+
+		l.MoveToFront(second)
+		assert.Equal(t, second, l.root.next)
+
+		l.MoveToFront(first)
+		assert.Equal(t, first, l.root.next)
+	})
+}