[Draft] [WinUI3] Window cleanup after test runs

[marcelwgn]

Fixes

When running the UI tests, the test apps window stays open and do not get cleaned up. There are two ways a window get's "leaked" when running tests from Visual Studio:

1. Test discovery starts app but does not close it
2. Test run finished (also does not close app)

This PR tries to address this, in it's current form, the second case would be fixed. Point one still occurs.

PR Type

What kind of change does this PR introduce?

• Bugfix

What is the current behavior?

Two windows spawn when running tests through Visual Studio, both stay open after test run finished.

What is the new behavior?

One window stays open, the other get's closed.

PR Checklist

Please check if your PR fulfills the following requirements:

• Tested code with current supported SDKs
• New component
  • Pull Request has been submitted to the documentation repository instructions. Link:
  • Added description of major feature to project description for NuGet package (4000 total character limit, so don't push entire description over that)
  • If control, added to Visual Studio Design project
• Sample in sample app has been added / updated (for bug fixes / features)
  • Icon has been created (if new sample) following the Thumbnail Style Guide and templates
• New major technical changes in the toolkit have or will be added to the Wiki e.g. build changes, source generators, testing infrastructure, sample creation changes, etc...
• Tests for the changes have been added (for bug fixes / features) (if applicable)
• Header has been added to all new source files (run build/UpdateHeaders.bat)
• Contains NO breaking changes

Other information

Case

[ghost]

Thanks chingucoding for opening a Pull Request! The reviewers will test the PR and highlight if there is any conflict or changes required. If the PR is approved we will proceed to merge the pull request 🙌

[azchohfi]

Is this only with TAEF or MSTest or both?

[marcelwgn]

I think VS is running the MSTest version, so MSTest.

[azchohfi]

Oh, my bad, this is the UnitTests, not the UI tests. I'll take a look at what might be happening. This should have been like this already.

[marcelwgn]

From what I can tell, the WinUI app does not realize that "it is done" or MSTest is not telling it that. UWP Apps don't seem to have that problem for some reason.