`NullReferenceException` in CI/CD since .NET Core Runtime version 3.1.28

[andyleejordan]

Prerequisites

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Steps to reproduce

Our last successful CI/CD pipeline used .NET Core Runtime version 3.1.27, and since the update to 3.1.28 it has consistently failed in the completion tests. The delegate which calls TabExpansion2 is now failing, resulting in a null reference exception (as it's not expected to throw). The inner exception is a file not found exception, where Microsoft.Bcl.AsyncInterfaces v1.0.0.0 and System.Threading.Tasks.Extensions v4.2.0.0 aren't being found.

Specifically this happens with PowerShell 5.1, which means when we're targeting .NET Desktop Framework 4.6.2.

I am hesitant to blame the .NET update...and yet I was able to immediately repro this locally as soon as I installed the same update.

This is currently blocking new releases.

Expected behavior

N/A

Actual behavior

N/A

Error details

Exception thrown: 'System.Management.Automation.MethodInvocationException' in System.Management.Automation.dll: 'Exception calling "CompleteInput" with "4" argument(s): "Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information."' Inner exceptions found, see $exception in variables window for more details. Innermost exception System.Reflection.ReflectionTypeLoadException : Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.
 at System.Reflection.RuntimeModule.GetTypes(RuntimeModule module)  at System.Reflection.RuntimeModule.GetTypes()  at System.Reflection.Assembly.GetTypes()  at System.Management.Automation.CompletionCompleters.<>c.<InitializeTypeCache>b__111_0(Assembly assembly)  at System.Linq.Enumerable.<SelectManyIterator>d__17`2.MoveNext()  at System.Management.Automation.CompletionCompleters.InitializeTypeCache()  at System.Management.Automation.CompletionCompleters.CompleteType(CompletionContext context, String prefix, String suffix)  at System.Management.Automation.CompletionAnalysis.GetResultHelper(CompletionContext completionContext, Int32& replacementIndex, Int32& replacementLength, Boolean isQuotedString)  at System.Management.Automation.CompletionAnalysis.GetResults(PowerShell powerShell, Int32& replacementIndex, Int32& replacementLength)  at System.Management.Automation.CommandCompletion.CompleteInputImpl(Ast ast, Token[] tokens, IScriptPosition positionOfCursor, Hashtable options)

Environment data

N/A

Version

N/A

Visuals

[andyleejordan]

At this point, we don't know what broke that test. We've skipped the test for now and unpinned .NET. It's completions on Windows PowerShell, which is fragile to begin with...unassigning as we're not actively investigating this mystery.

[andyleejordan]

This has never cropped up as causing an issue for users, closing.