[#667] writecache: Fix flush test

Allow to disable background flusher for testing purposes.

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/local_object_storage/writecache/writecachebadger/flush.go

@@ -97,6 +97,9 @@ func (c *collector) send(ctx context.Context, cancel func(), buf *z.Buffer) erro
 
 // runFlushLoop starts background workers which periodically flush objects to the blobstor.
 func (c *cache) runFlushLoop(ctx context.Context) {
+	if c.disableBackgroundFlush {
+		return
+	}
 	for i := 0; i < c.workersCount; i++ {
 		c.wg.Add(1)
 		go c.workerFlushSmall(ctx)

pkg/local_object_storage/writecache/writecachebadger/flush_test.go

@@ -28,6 +28,7 @@ func TestFlush(t *testing.T) {
 				WithMetabase(mb),
 				WithBlobstor(bs),
 				WithGCInterval(1 * time.Second),
+				WithDisableBackgroundFlush(),
 			}, opts...)...)
 	}
 

pkg/local_object_storage/writecache/writecachebadger/options.go

@@ -34,6 +34,8 @@ type options struct {
 	metrics writecache.Metrics
 	// gcInterval is the interval duration to run the GC cycle.
 	gcInterval time.Duration
+	// disableBackgroundFlush is for testing purposes only.
+	disableBackgroundFlush bool
 }
 
 // WithLogger sets logger.
@@ -108,3 +110,10 @@ func WithGCInterval(d time.Duration) Option {
 		o.gcInterval = d
 	}
 }
+
+// WithDisableBackgroundFlush disables background flush, for testing purposes only.
+func WithDisableBackgroundFlush() Option {
+	return func(o *options) {
+		o.disableBackgroundFlush = true
+	}
+}