DUnit GUI Testing: Can I force 'Application' to a different "form"?
I'm trying to run a GUI unit test with DUnit to an application whose mainform creates dynamically frames to itself. I've been able to create the application-to-test's mainform as a form in the test case and access its menu items etc.

The problem comes when the application tries to create a frame dynamically. The frame's resource reading comes to a point where it needs the window handle (in my case, setting the caption of a tab sheet). Here it goes from TWinControl.GetHandle to TWinControl.CreateWnd and to TCustomFrame.CreateParams.

In this CreateParams, the code says:

      if Parent = nil then
        Params.WndParent := Application.Handle;

This is where the difference occurs. When I run the actual application (not in the test), the Application.Handle here returns a non-zero number and the flow continues ok. But in the DUnit test application, the Application.Handle here returns 0. This causes the code in the TWinControl.CreateWnd to raise an exception telling that the frame does not have a parent:

      with Params do
      begin
        if (WndParent = 0) and (Style and WS_CHILD <> 0) then
          if (Owner <> nil) and (csReading in Owner.ComponentState) and
            (Owner is TWinControl) then
            WndParent := TWinControl(Owner).Handle
          else
            raise EInvalidOperation.CreateFmt(SParentRequired, [Name]);

I'd like to try to get around this problem (and in general, all test problems) without modifying the "production" code just because of the tests. Can you provide any clues on whether I could somehow force the "Application" to something else, or in some other way work around this?

Looking at the code, a possible other workaround scenario might be to try to get the owner (which is my "MainForm" of the application-to-test, i.e. whose handle I'd want to get) to be in csReading state while doing this frame creation in the test, but at least initially it doesn't seem so straightforward to get this to happen either.
DUnit GUI Testing: Can I force 'Application' to a different "form"?
===

I'm trying to run a GUI unit test with DUnit to an application whose mainform creates dynamically frames to itself. I've been able to create the application-to-test's mainform as a form in the test case and access its menu items etc.

The problem comes when the application tries to create a frame dynamically. The frame's resource reading comes to a point where it needs the window handle (in my case, setting the caption of a tab sheet). Here it goes from TWinControl.GetHandle to TWinControl.CreateWnd and to TCustomFrame.CreateParams.

In this CreateParams, the code says:

      if Parent = nil then
        Params.WndParent := Application.Handle;

This is where the difference occurs. When I run the actual application (not in the test), the Application.Handle here returns a non-zero number and the flow continues ok. But in the DUnit test application, the Application.Handle here returns 0. This causes the code in the TWinControl.CreateWnd to raise an exception telling that the frame does not have a parent:

      with Params do
      begin
        if (WndParent = 0) and (Style and WS_CHILD <> 0) then
          if (Owner <> nil) and (csReading in Owner.ComponentState) and
            (Owner is TWinControl) then
            WndParent := TWinControl(Owner).Handle
          else
            raise EInvalidOperation.CreateFmt(SParentRequired, [Name]);

I'd like to try to get around this problem (and in general, all test problems) without modifying the "production" code just because of the tests. Can you provide any clues on whether I could somehow force the "Application" to something else, or in some other way work around this?

Looking at the code, a possible other workaround scenario might be to try to get the owner (which is my "MainForm" of the application-to-test, i.e. whose handle I'd want to get) to be in csReading state while doing this frame creation in the test, but at least initially it doesn't seem so straightforward to get this to happen either.