You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: transaction_manager_existing_workflow_test.go
    path of file: ./repos/temporal/service/history/ndc
    
    the code of the file until where you have to start completion: // The MIT License
//
// Copyright (c) 2020 Temporal Technologies Inc.  All rights reserved.
//
// Copyright (c) 2020 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
    
func (s *transactionMgrForExistingWorkflowSuite) TestDispatchForExistingWorkflow_NoRebuild_CurrentWorkflowNotGuaranteed_IsCurrent() {
	ctx := context.Background()

	namespaceID := namespace.ID("some random namespace ID")
	workflowID := "some random workflow ID"
	targetRunID := "some random run ID"

	isWorkflowRebuilt := false

	targetWorkflow := NewMockWorkflow(s.controller)
	targetMutableState := workflow.NewMockMutableState(s.controller)
	targetWorkflow.EXPECT().GetMutableState().Return(targetMutableState).AnyTimes()

	newWorkflow := NewMockWorkflow(s.controller)

	targetMutableState.EXPECT().IsCurrentWorkflowGuaranteed().Return(false).AnyTimes()
	targetMutableState.EXPECT().GetExecutionInfo().Return(&persistencespb.WorkflowExecutionInfo{
		NamespaceId: namespaceID.String(),
		WorkflowId:  workflowID,
	}).AnyTimes()
	targetMutableState.EXPECT().GetExecutionState().Return(&persistencespb.WorkflowExecutionState{
		RunId: targetRunID,
	}).AnyTimes()
	s.mockTransactionMgr.EXPECT().GetCurrentWorkflowRunID(ctx, namespaceID, workflowID).Return(targetRunID, nil)

	err := s.updateMgr.dispatchForExistingWorkflow(ctx, isWorkflowRebuilt, targetWorkflow, newWorkflow)
	s.Error(err)
}