feat: support ARC for DNS cache

common/lru/lrucache_test.go

@@ -0,0 +1,184 @@
+package lru
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var entries = []struct {
+	key   string
+	value string
+}{
+	{"1", "one"},
+	{"2", "two"},
+	{"3", "three"},
+	{"4", "four"},
+	{"5", "five"},
+}
+
+func TestLRUCache(t *testing.T) {
+	c := New[string, string]()
+
+	for _, e := range entries {
+		c.Set(e.key, e.value)
+	}
+
+	c.Delete("missing")
+	_, ok := c.Get("missing")
+	assert.False(t, ok)
+
+	for _, e := range entries {
+		value, ok := c.Get(e.key)
+		if assert.True(t, ok) {
+			assert.Equal(t, e.value, value)
+		}
+	}
+
+	for _, e := range entries {
+		c.Delete(e.key)
+
+		_, ok := c.Get(e.key)
+		assert.False(t, ok)
+	}
+}
+
+func TestLRUMaxAge(t *testing.T) {
+	c := New[string, string](WithAge[string, string](86400))
+
+	now := time.Now().Unix()
+	expected := now + 86400
+
+	// Add one expired entry
+	c.Set("foo", "bar")
+	c.lru.Back().Value.expires = now
+
+	// Reset
+	c.Set("foo", "bar")
+	e := c.lru.Back().Value
+	assert.True(t, e.expires >= now)
+	c.lru.Back().Value.expires = now
+
+	// Set a few and verify expiration times
+	for _, s := range entries {
+		c.Set(s.key, s.value)
+		e := c.lru.Back().Value
+		assert.True(t, e.expires >= expected && e.expires <= expected+10)
+	}
+
+	// Make sure we can get them all
+	for _, s := range entries {
+		_, ok := c.Get(s.key)
+		assert.True(t, ok)
+	}
+
+	// Expire all entries
+	for _, s := range entries {
+		le, ok := c.cache[s.key]
+		if assert.True(t, ok) {
+			le.Value.expires = now
+		}
+	}
+
+	// Get one expired entry, which should clear all expired entries
+	_, ok := c.Get("3")
+	assert.False(t, ok)
+	assert.Equal(t, c.lru.Len(), 0)
+}
+
+func TestLRUpdateOnGet(t *testing.T) {
+	c := New[string, string](WithAge[string, string](86400), WithUpdateAgeOnGet[string, string]())
+
+	now := time.Now().Unix()
+	expires := now + 86400/2
+
+	// Add one expired entry
+	c.Set("foo", "bar")
+	c.lru.Back().Value.expires = expires
+
+	_, ok := c.Get("foo")
+	assert.True(t, ok)
+	assert.True(t, c.lru.Back().Value.expires > expires)
+}
+
+func TestMaxSize(t *testing.T) {
+	c := New[string, string](WithSize[string, string](2))
+	// Add one expired entry
+	c.Set("foo", "bar")
+	_, ok := c.Get("foo")
+	assert.True(t, ok)
+
+	c.Set("bar", "foo")
+	c.Set("baz", "foo")
+
+	_, ok = c.Get("foo")
+	assert.False(t, ok)
+}
+
+func TestExist(t *testing.T) {
+	c := New[int, int](WithSize[int, int](1))
+	c.Set(1, 2)
+	assert.True(t, c.Exist(1))
+	c.Set(2, 3)
+	assert.False(t, c.Exist(1))
+}
+
+func TestEvict(t *testing.T) {
+	temp := 0
+	evict := func(key int, value int) {
+		temp = key + value
+	}
+
+	c := New[int, int](WithEvict[int, int](evict), WithSize[int, int](1))
+	c.Set(1, 2)
+	c.Set(2, 3)
+
+	assert.Equal(t, temp, 3)
+}
+
+func TestSetWithExpire(t *testing.T) {
+	c := New[int, *struct{}](WithAge[int, *struct{}](1))
+	now := time.Now().Unix()
+
+	tenSecBefore := time.Unix(now-10, 0)
+	c.SetWithExpire(1, &struct{}{}, tenSecBefore)
+
+	// res is expected not to exist, and expires should be empty time.Time
+	res, expires, exist := c.GetWithExpire(1)
+
+	assert.True(t, nil == res)
+	assert.Equal(t, time.Time{}, expires)
+	assert.Equal(t, false, exist)
+}
+
+func TestStale(t *testing.T) {
+	c := New[int, int](WithAge[int, int](1), WithStale[int, int](true))
+	now := time.Now().Unix()
+
+	tenSecBefore := time.Unix(now-10, 0)
+	c.SetWithExpire(1, 2, tenSecBefore)
+
+	res, expires, exist := c.GetWithExpire(1)
+	assert.Equal(t, 2, res)
+	assert.Equal(t, tenSecBefore, expires)
+	assert.Equal(t, true, exist)
+}
+
+func TestCloneTo(t *testing.T) {
+	o := New[string, int](WithSize[string, int](10))
+	o.Set("1", 1)
+	o.Set("2", 2)
+
+	n := New[string, int](WithSize[string, int](2))
+	n.Set("3", 3)
+	n.Set("4", 4)
+
+	o.CloneTo(n)
+
+	assert.False(t, n.Exist("3"))
+	assert.True(t, n.Exist("1"))
+
+	n.Set("5", 5)
+	assert.False(t, n.Exist("1"))
+}