Merge pull request onflow#6862 from The-K-R-O-K/AndriiDiachuk/TestMes…

…sageIndexTransactionStatusesProviderResponse_HappyPath-fix-flaky-test

TestMessageIndexTransactionStatusesProviderResponse_HappyPath test being flaky.

engine/access/rest/websockets/data_providers/transaction_statuses_provider_test.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strconv"
 	"testing"
+	"time"
 
 	"github.com/rs/zerolog"
 	"github.com/stretchr/testify/mock"
@@ -223,7 +224,7 @@ func (s *TransactionStatusesProviderSuite) TestMessageIndexTransactionStatusesPr
 	// Create a mock subscription and mock the channel
 	sub := ssmock.NewSubscription(s.T())
 	sub.On("Channel").Return((<-chan interface{})(txStatusesChan))
-	sub.On("Err").Return(nil)
+	sub.On("Err").Return(nil).Once()
 
 	s.api.On(
 		"SubscribeTransactionStatusesFromStartBlockID",
@@ -255,7 +256,9 @@ func (s *TransactionStatusesProviderSuite) TestMessageIndexTransactionStatusesPr
 	defer provider.Close()
 
 	// Run the provider in a separate goroutine to simulate subscription processing
+	done := make(chan struct{})
 	go func() {
+		defer close(done)
 		err = provider.Run()
 		s.Require().NoError(err)
 	}()
@@ -282,6 +285,9 @@ func (s *TransactionStatusesProviderSuite) TestMessageIndexTransactionStatusesPr
 		responses = append(responses, txStatusesRes)
 	}
 
+	// Wait for the provider goroutine to finish
+	unittest.RequireCloseBefore(s.T(), done, time.Second, "provider failed to stop")
+
 	// Verifying that indices are starting from 0
 	s.Require().Equal(uint64(0), responses[0].MessageIndex, "Expected MessageIndex to start with 0")