cache_test.go

package cache

import (
	"runtime"
	"sync"
	"testing"
	"time"
)

type TestStruct struct {
	Num      int
	Children []*TestStruct
}

const DefaultExpiration time.Duration = 0

func TestCache(t *testing.T) {
	tc := New(DefaultExpiration)

	a, found := tc.Get("a")
	if found || a != nil {
		t.Error("Getting A found value that shouldn't exist:", a)
	}

	b, found := tc.Get("b")
	if found || b != nil {
		t.Error("Getting B found value that shouldn't exist:", b)
	}

	c, found := tc.Get("c")
	if found || c != nil {
		t.Error("Getting C found value that shouldn't exist:", c)
	}

	tc.Set("a", 1)
	tc.Set("b", "b")
	tc.Set("c", 3.5)

	x, found := tc.Get("a")
	if !found {
		t.Error("a was not found while getting a2")
	}
	if x == nil {
		t.Error("x for a is nil")
	} else if a2 := x.(int); a2+2 != 3 {
		t.Error("a2 (which should be 1) plus 2 does not equal 3; value:", a2)
	}

	x, found = tc.Get("b")
	if !found {
		t.Error("b was not found while getting b2")
	}
	if x == nil {
		t.Error("x for b is nil")
	} else if b2 := x.(string); b2+"B" != "bB" {
		t.Error("b2 (which should be b) plus B does not equal bB; value:", b2)
	}

	x, found = tc.Get("c")
	if !found {
		t.Error("c was not found while getting c2")
	}
	if x == nil {
		t.Error("x for c is nil")
	} else if c2 := x.(float64); c2+1.2 != 4.7 {
		t.Error("c2 (which should be 3.5) plus 1.2 does not equal 4.7; value:", c2)
	}

	z := tc.GetAll()
	if len(z) != 3 {
		t.Errorf("expected to receive a, b, c, received: %+v\n", z)
	}
}

func TestStorePointerToStruct(t *testing.T) {
	tc := New(DefaultExpiration)
	tc.Set("foo", &TestStruct{Num: 1})
	x, found := tc.Get("foo")
	if !found {
		t.Fatal("*TestStruct was not found for foo")
	}
	foo := x.(*TestStruct)
	foo.Num++

	y, found := tc.Get("foo")
	if !found {
		t.Fatal("*TestStruct was not found for foo (second time)")
	}
	bar := y.(*TestStruct)
	if bar.Num != 2 {
		t.Fatal("TestStruct.Num is not 2")
	}
}

func TestReplace(t *testing.T) {
	tc := New(DefaultExpiration)
	err := tc.Replace("foo", "bar")
	if err == nil {
		t.Error("Replaced foo when it shouldn't exist")
	}
	tc.Set("foo", "bar")
	err = tc.Replace("foo", "bar")
	if err != nil {
		t.Error("Couldn't replace existing key foo")
	}
}

func TestDelete(t *testing.T) {
	tc := New(DefaultExpiration)
	tc.Set("foo", "bar")
	tc.Delete("foo")
	x, found := tc.Get("foo")
	if found {
		t.Error("foo was found, but it should have been deleted")
	}
	if x != nil {
		t.Error("x is not nil:", x)
	}
}

func TestItemCount(t *testing.T) {
	tc := New(DefaultExpiration)
	tc.Set("foo", "1")
	tc.Set("bar", "2")
	tc.Set("baz", "3")
	if n := tc.ItemCount(); n != 3 {
		t.Errorf("Item count is not 3: %d", n)
	}
}

func TestFlush(t *testing.T) {
	tc := New(DefaultExpiration)
	tc.Set("foo", "bar")
	tc.Set("baz", "yes")
	tc.Flush()
	x, found := tc.Get("foo")
	if found {
		t.Error("foo was found, but it should have been deleted")
	}
	if x != nil {
		t.Error("x is not nil:", x)
	}
	x, found = tc.Get("baz")
	if found {
		t.Error("baz was found, but it should have been deleted")
	}
	if x != nil {
		t.Error("x is not nil:", x)
	}
}

func BenchmarkCacheGetExpiring(b *testing.B) {
	benchmarkCacheGet(b, 5*time.Minute)
}

func BenchmarkCacheGetNotExpiring(b *testing.B) {
	benchmarkCacheGet(b, 0)
}

func benchmarkCacheGet(b *testing.B, exp time.Duration) {
	b.StopTimer()
	tc := New(exp)
	tc.Set("foo", "bar")
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		tc.Get("foo")
	}
}

func BenchmarkRWMutexMapGet(b *testing.B) {
	b.StopTimer()
	m := map[string]string{
		"foo": "bar",
	}
	mu := sync.RWMutex{}
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		mu.RLock()
		_, _ = m["foo"]
		mu.RUnlock()
	}
}

func BenchmarkRWMutexInterfaceMapGetStruct(b *testing.B) {
	b.StopTimer()
	s := struct{ name string }{name: "foo"}
	m := map[interface{}]string{
		s: "bar",
	}
	mu := sync.RWMutex{}
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		mu.RLock()
		_, _ = m[s]
		mu.RUnlock()
	}
}

func BenchmarkRWMutexInterfaceMapGetString(b *testing.B) {
	b.StopTimer()
	m := map[interface{}]string{
		"foo": "bar",
	}
	mu := sync.RWMutex{}
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		mu.RLock()
		_, _ = m["foo"]
		mu.RUnlock()
	}
}

func BenchmarkCacheGetConcurrentExpiring(b *testing.B) {
	benchmarkCacheGetConcurrent(b, 5*time.Minute)
}

func BenchmarkCacheGetConcurrentNotExpiring(b *testing.B) {
	benchmarkCacheGetConcurrent(b, 0)
}

func benchmarkCacheGetConcurrent(b *testing.B, exp time.Duration) {
	b.StopTimer()
	tc := New(exp)
	tc.Set("foo", "bar")
	wg := new(sync.WaitGroup)
	workers := runtime.NumCPU()
	each := b.N / workers
	wg.Add(workers)
	b.StartTimer()
	for i := 0; i < workers; i++ {
		go func() {
			for j := 0; j < each; j++ {
				tc.Get("foo")
			}
			wg.Done()
		}()
	}
	wg.Wait()
}

func BenchmarkRWMutexMapGetConcurrent(b *testing.B) {
	b.StopTimer()
	m := map[string]string{
		"foo": "bar",
	}
	mu := sync.RWMutex{}
	wg := new(sync.WaitGroup)
	workers := runtime.NumCPU()
	each := b.N / workers
	wg.Add(workers)
	b.StartTimer()
	for i := 0; i < workers; i++ {
		go func() {
			for j := 0; j < each; j++ {
				mu.RLock()
				_, _ = m["foo"]
				mu.RUnlock()
			}
			wg.Done()
		}()
	}
	wg.Wait()
}

func benchmarkCacheSet(b *testing.B, exp time.Duration) {
	b.StopTimer()
	tc := New(exp)
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		tc.Set("foo", "bar")
	}
}

func BenchmarkRWMutexMapSet(b *testing.B) {
	b.StopTimer()
	m := map[string]string{}
	mu := sync.RWMutex{}
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		mu.Lock()
		m["foo"] = "bar"
		mu.Unlock()
	}
}

func BenchmarkCacheSetDelete(b *testing.B) {
	b.StopTimer()
	tc := New(DefaultExpiration)
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		tc.Set("foo", "bar")
		tc.Delete("foo")
	}
}

func BenchmarkRWMutexMapSetDelete(b *testing.B) {
	b.StopTimer()
	m := map[string]string{}
	mu := sync.RWMutex{}
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		mu.Lock()
		m["foo"] = "bar"
		mu.Unlock()
		mu.Lock()
		delete(m, "foo")
		mu.Unlock()
	}
}

func BenchmarkCacheSetDeleteSingleLock(b *testing.B) {
	b.StopTimer()
	tc := New(DefaultExpiration)
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		tc.mu.Lock()
		tc.set("foo", "bar")
		tc.Delete("foo")
		tc.mu.Unlock()
	}
}

func BenchmarkRWMutexMapSetDeleteSingleLock(b *testing.B) {
	b.StopTimer()
	m := map[string]string{}
	mu := sync.RWMutex{}
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		mu.Lock()
		m["foo"] = "bar"
		delete(m, "foo")
		mu.Unlock()
	}
}