App.config is not created when Settings are modified

[RussKie]

Porting from AB#1386445 for public awareness.

Summary

I debugged and narrowed the problem down to the following code:

project-system/src/Microsoft.VisualStudio.Editors/SettingsDesigner/AppConfigSerializer.vb

Lines 188 to 196 in 893e4d2

	Try
	VSErrorHandler.ThrowOnFailure(ProjSpecialFiles.GetFile(__PSFFILEID.PSFFILEID_AppConfig, Flags, AppConfigItemId, AppConfigFileName))
	Catch ex As System.Runtime.InteropServices.COMException When ex.ErrorCode = Interop.Win32Constant.OLE_E_PROMPTSAVECANCELLED
	Throw New ComponentModel.Design.CheckoutException(My.Resources.Microsoft_VisualStudio_Editors_Designer.DFX_UnableToCheckout, ex)
	Catch ex As Exception When TypeOf ex IsNot ComponentModel.Design.CheckoutException
	' VsWhidbey 224145, ProjSpecialFiles.GetFile(create:=true) fails on vbexpress sku
	AppConfigItemId = VSITEMID.NIL
	Debug.Fail(String.Format("ProjSpecialFiles.GetFile (create={0}) failed: {1}", CreateIfNotExists, ex))
	End Try

When attempting to get the file with __PSFFLAGS.PSFF_CreateIfNotExist Or __PSFFLAGS.PSFF_FullPath fails with the following error:

   at EnvDTE80.Solution2.GetProjectItemTemplate(String TemplateName, String Language)
   at Microsoft.VisualStudio.ProjectSystem.VS.CreateFileFromTemplateService.<CreateFileAsync>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.GetResult()
   at Microsoft.VisualStudio.ProjectSystem.SpecialFileProviders.AbstractSpecialFileProvider.<CreateDefaultFileAsync>d__6.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at Microsoft.VisualStudio.ProjectSystem.SpecialFileProviders.AbstractSpecialFileProvider.<GetFileAsync>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode.<GetSpecialFilePathAsync>d__557.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode.<>c__DisplayClass508_0.<<GetFile>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.Threading.JoinableTask.CompleteOnCurrentThread()
   at Microsoft.VisualStudio.ProjectSystem.ProjectMultiThreadedService.ExecuteSynchronously(Func`1 asyncAction)
   at Microsoft.VisualStudio.ProjectSystem.VS.HResult.<>c__DisplayClass37_0.<Invoke>b__0()
   at Microsoft.VisualStudio.ProjectSystem.VS.HResult.Invoke(Func`1 action, IServiceProvider vsShellServiceProvider, IProjectFaultHandlerService projectFaultHandlerService, UnconfiguredProject project)

Narrowed down more, this is what's causing the error - the zip file isn't getting found

I can speculate that https://devdiv.visualstudio.com/DevDiv/_git/VS?path=/src/vsproject/Templates/Windows/CSharp/ItemTemplates/AppConfigInternal is either not getting built, or the archive isn't getting packaged...

Expected Behavior

The app.config is being created whenever settings are changed.

User Impact

Wide, e.g., https://stackoverflow.com/q/65518159

[tmeschter]

@melytc @drewnoakes One to consider as you look at VB work for 17.2.