package batcher import ( "sync" "sync/atomic" "testing" "time" "github.com/stretchr/testify/require" "gitlab.com/slon/shad-go/batcher/slow" ) func TestSimple(t *testing.T) { var value slow.Value b := NewBatcher(&value) value.Store(1) require.Equal(t, 1, b.Load()) require.Equal(t, 1, value.Load()) value.Store(2) require.Equal(t, 2, b.Load()) require.Equal(t, 2, value.Load()) } func TestStaleRead(t *testing.T) { const ( N = 100 K = 100 M = 10 ) var value slow.Value b := NewBatcher(&value) var counter int32 value.Store(counter) var wg sync.WaitGroup for i := 0; i < N; i++ { wg.Add(1) go func(i int) { defer wg.Done() time.Sleep(time.Millisecond * time.Duration(i/N)) for j := 0; j < K; j++ { counterValue := atomic.LoadInt32(&counter) batcherValue := b.Load().(int32) if batcherValue < counterValue { t.Errorf("load returned old value: counter=%d, batcher=%d", counterValue, batcherValue) return } } }(i) } for i := 0; i < M*K; i++ { // value is always greater than counter value.Store(int32(i)) atomic.StoreInt32(&counter, int32(i)) time.Sleep(time.Millisecond / M) } wg.Wait() } func TestSpeed(t *testing.T) { const ( N = 100 K = 200 ) var value slow.Value b := NewBatcher(&value) start := time.Now() var wg sync.WaitGroup for i := 0; i < N; i++ { wg.Add(1) go func() { defer wg.Done() for i := 0; i < K; i++ { b.Load() } }() } wg.Wait() require.Truef(t, time.Since(start) < time.Second, "batching it too slow") }