We have a windows application in VB6.0. As of now there no automated tests exists for this application. We need to start writing testing automation(unit tests and UI tests) for this application. But it is expected that it may migrate to new VB.NET or C#.NET based windows application(either WinForms or WPF) or it may migrate to Web Application. Before starting I need an idea which tool to use which can be used to write automated tests(unit and UI tests) so that it may remain applicable current application in VB6.0 and in future migrated application in such a way that we may not have to write the automation again for migrated applcation and ensures that the tests doesn't break after migration and we also feel reliable that functionality of application doesn't break after migration.Intent is same automation tests should be applicable for current and future migration; where we can run the same automated tests ensuring there is no breakage in functionality.
Note:
1. Migration is not decided yet but it may be a Windows Application(WinForms/WPF) or Web Application in VB.NET or in C#.NET.
2. We are using 3rd party controls as well (ComponentStudioOne-ActiveX) in current VB6.0 Windows application.
3. Controls are loading dynamically.