Error for unused operation

internal/client.go

@@ -746,7 +746,7 @@ type (
 		// workflow completion callback. Only settable by the SDK - e.g. [temporalnexus.workflowRunOperation].
 		callbacks []*commonpb.Callback
 		// links. Only settable by the SDK - e.g. [temporalnexus.workflowRunOperation].
-		links     []*commonpb.Link
+		links []*commonpb.Link
 	}
 
 	// WithStartWorkflowOperation is a type of operation that can be executed as part of a workflow start.
@@ -1082,6 +1082,9 @@ func (op *UpdateWithStartWorkflowOperation) Get(ctx context.Context) (WorkflowUp
 	case <-op.doneCh:
 		return op.handle, op.err
 	case <-ctx.Done():
+		if !op.executed.Load() {
+			return nil, fmt.Errorf("operation was not executed: %v", ctx.Err())
+		}
 		return nil, ctx.Err()
 	}
 }

internal/internal_workflow_client_test.go

@@ -1027,6 +1027,34 @@ func (s *workflowRunSuite) TestExecuteWorkflowWithUpdate_Retry() {
 	s.NoError(err)
 }
 
+func (s *workflowRunSuite) TestExecuteWorkflowWithUpdate_OperationNotExecuted() {
+	s.workflowServiceClient.EXPECT().StartWorkflowExecution(gomock.Any(), gomock.Any(), gomock.Any()).
+		Return(&workflowservice.StartWorkflowExecutionResponse{
+			RunId: runID,
+		}, nil)
+
+	updOp := NewUpdateWithStartWorkflowOperation(
+		UpdateWorkflowOptions{
+			UpdateName:   "update",
+			WaitForStage: WorkflowUpdateStageCompleted,
+		})
+
+	ctxWithTimeout, cancel := context.WithTimeout(context.Background(), 500*time.Millisecond)
+	defer cancel()
+
+	_, err := s.workflowClient.ExecuteWorkflow(
+		ctxWithTimeout,
+		StartWorkflowOptions{
+			ID:        workflowID,
+			TaskQueue: taskqueue,
+			// WithStartOperation is not specified!
+		}, workflowType,
+	)
+
+	_, err = updOp.Get(ctxWithTimeout)
+	require.EqualError(s.T(), err, "operation was not executed: context deadline exceeded")
+}
+
 func (s *workflowRunSuite) TestExecuteWorkflowWithUpdate_Abort() {
 	tests := []struct {
 		name        string