Fix race condition in robustness watch creation due to slices reallocation

Signed-off-by: Marek Siarkowicz <[email protected]>

Author: serathius

tests/robustness/client/client.go

@@ -306,18 +306,22 @@ func (c *RecordingClient) watch(ctx context.Context, request model.WatchRequest)
 	}
 	respCh := make(chan clientv3.WatchResponse)
 
+	responses := []model.WatchResponse{}
 	c.watchMux.Lock()
 	c.watchOperations = append(c.watchOperations, model.WatchOperation{
 		Request:   request,
-		Responses: []model.WatchResponse{},
+		Responses: responses,
 	})
 	index := len(c.watchOperations) - 1
 	c.watchMux.Unlock()
 
 	go func() {
 		defer close(respCh)
 		for r := range c.client.Watch(ctx, request.Key, ops...) {
-			c.watchOperations[index].Responses = append(c.watchOperations[index].Responses, ToWatchResponse(r, c.baseTime))
+			responses = append(responses, ToWatchResponse(r, c.baseTime))
+			c.watchMux.Lock()
+			c.watchOperations[index].Responses = responses
+			c.watchMux.Unlock()
 			select {
 			case respCh <- r:
 			case <-ctx.Done():