RichSuggestBox Intermittent Test Failures

[michael-hawker]

Describe the bug

At least some part of #347 seem to be intermittent failures in the RichSuggestBox tests as well

Here:

Windows/components/RichSuggestBox/tests/Test_RichSuggestBox.cs

Line 143 in 2c0f9b3

Assert.AreEqual(2, rsb.Tokens.Count, "Unexpected token count after adding.");

And here:

Windows/components/RichSuggestBox/tests/Test_RichSuggestBox.cs

Line 308 in 2c0f9b3

Assert.AreEqual(2, rsb.Tokens.Count, "Unexpected tokens count after load.");

Both involving adding new tokens.

This seems to more often happen for WinUI 3, so possibly has to do with different behavior or regression there? But something definitely seems to be wonky and unstable here with this control and these tests.

Failed Test_RichSuggestBox_DeleteTokens (@Token1,#Token2) [108 ms]
  Error Message:
   Assert.AreEqual failed. Expected:<2>. Actual:<1>. Unexpected token count after adding.
  Stack Trace:
     at RichSuggestBoxExperiment.Tests.Test_RichSuggestBox.<>c__DisplayClass2_0.<<Test_RichSuggestBox_DeleteTokens>b__0>d.MoveNext() in D:\a\Windows\Windows\components\RichSuggestBox\tests\Test_RichSuggestBox.cs:line 143
--- End of stack trace from previous location ---
   at CommunityToolkit.WinUI.DispatcherQueueExtensions.<>c__DisplayClass3_0.<<EnqueueAsync>b__1>d.MoveNext() in /_/components/Extensions/src/Dispatcher/DispatcherQueueExtensions.cs:line 180
--- End of stack trace from previous location ---
   at RichSuggestBoxExperiment.Tests.Test_RichSuggestBox.Test_RichSuggestBox_DeleteTokens(String token1, String token2) in D:\a\Windows\Windows\components\RichSuggestBox\tests\Test_RichSuggestBox.cs:line 133
   at Microsoft.VisualStudio.TestPlatform.MSTestAdapter.PlatformServices.ThreadOperations.ExecuteWithAbortSafety(Action action)

It's unclear if this is some underlying issue with the platform, or some race condition with us not waiting long enough in the test. But it needs investigation so we can have a more stable CI setup.

Steps to reproduce

Intermittent test failure

Expected behavior

Tokens always added

Screenshots

No response

Code Platform

• UWP
• WinAppSDK / WinUI 3
• Web Assembly (WASM)
• Android
• iOS
• MacOS
• Linux / GTK

Windows Build Number

• Windows 10 1809 (Build 17763)
• Windows 10 1903 (Build 18362)
• Windows 10 1909 (Build 18363)
• Windows 10 2004 (Build 19041)
• Windows 10 20H2 (Build 19042)
• Windows 10 21H1 (Build 19043)
• Windows 10 21H2 (Build 19044)
• Windows 10 22H2 (Build 19045)
• Windows 11 21H2 (Build 22000)
• Other (specify)

Other Windows Build number

No response

App minimum and target SDK version

• Windows 10, version 1809 (Build 17763)
• Windows 10, version 1903 (Build 18362)
• Windows 10, version 1909 (Build 18363)
• Windows 10, version 2004 (Build 19041)
• Windows 10, version 2104 (Build 20348)
• Windows 11, version 22H2 (Build 22000)
• Other (specify)

Other SDK version

No response

Visual Studio Version

No response

Visual Studio Build Number

No response

Device form factor

No response

Additional context

No response

Help us help you

Yes, but only if others can assist.

[michael-hawker]

Before these asserts we should wait for the UI to update, like we do in other tests:

Windows/components/Primitives/tests/SwitchPresenter/SwitchPresenterTests.cs

Lines 40 to 41 in 605cd43

	// Wait for update
	await CompositionTargetHelper.ExecuteAfterCompositionRenderingAsync(() => { });

See if that helps.

There's probably a few places in these tests we can do this and remove the Delay.