Fix System.MissingMethodException for KeyValuePair Deconstruction

[Copilot]

Overview

This PR addresses an issue where tests fail with a System.MissingMethodException when using MSTest v3.8.3 with .NET 6 projects. The error occurs because tuple deconstruction of KeyValuePair<TKey,TValue> requires the Polyfills.Polyfill.Deconstruct method, which is not available in the netstandard2.0 version of the assembly when used with .NET 6 projects.

Problem

The error occurs in the following scenario:

• When using MSTest v3.8.3 with .NET 6 projects
• The netstandard2.0 version of the assembly is being used
• Code in TestExecutionManager.cs, TestRunCancellationToken.cs, and DeploymentItemUtility.cs uses tuple deconstruction syntax that requires a polyfill implementation

Error message:

System.MissingMethodException: Method not found: 'Void Polyfills.Polyfill.Deconstruct(System.Collections.Generic.KeyValuePair`2<!!0,!!1>, !!0 ByRef, !!1 ByRef)'.

Changes

The changes replace tuple deconstruction pattern with traditional KeyValuePair access:

1. In TestExecutionManager.cs:

   • Changed foreach ((TestProperty key, object? value) in tcmProperties) to use standard KeyValuePair syntax
   • Changed foreach ((string key, object value) in sourceLevelParameters) to use standard KeyValuePair syntax

2. In TestRunCancellationToken.cs:

   • Changed the ConcurrentBag collection from ValueTuple to Tuple
   • Updated the foreach loop to access tuple items using .Item1 and .Item2
   • Updated the Register methods to create proper Tuple objects
   • Added missing using directives

3. In DeploymentItemUtility.cs:

   • Changed foreach ((string? key, string? value) in deploymentItemsData) to use standard KeyValuePair syntax

These changes avoid the need for the Polyfill.Deconstruct method while maintaining the same functionality.

Fixes #5579.

Warning

Firewall rules blocked me from connecting to one or more addresses

I tried to connect to the following addresses, but was blocked by firewall rules:

• pkgs.dev.azure.com
  • Triggering command: /home/REDACTED/work/testfx/testfx/.dotnet/dotnet msbuild /m /nologo /clp:Summary /v:minimal /nr:true /warnaserror /p:TreatWarningsAsErrors=true /p:ContinuousIntegrationBuild=false /home/REDACTED/work/testfx/testfx/artifacts/toolset/restore.proj /t:__WriteToolsetLocation /clp:ErrorsOnly;NoSummary /p:__ToolsetLocationOutputFile=/home/REDACTED/work/testfx/testfx/artifacts/toolset/10.0.0-beta.25229.4.txt (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to my firewall allow list

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[Youssef1313]

@nohwnd While it's still mysterious why restore isn't behaving as we would expect in the original issue, and we didn't get a binlog from the customer, I think this change is reasonable enough to avoid potential issues.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 74.05%. Comparing base (b44fb4e) to head (e08f8fd).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5633      +/-   ##
==========================================
- Coverage   76.51%   74.05%   -2.46%     
==========================================
  Files         602      602              
  Lines       36561    36560       -1     
==========================================
- Hits        27974    27074     -900     
- Misses       8587     9486     +899     

Flag	Coverage Δ
Debug	74.05% <100.00%> (-2.46%)	⬇️
integration	74.05% <100.00%> (-2.46%)	⬇️
production	74.05% <100.00%> (-2.46%)	⬇️
unit	74.05% <100.00%> (-2.47%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...Test.TestAdapter/Execution/TestExecutionManager.cs	82.59% <100.00%> (ø)
...latformServices/Utilities/DeploymentItemUtility.cs	93.61% <100.00%> (ø)

... and 67 files with indirect coverage changes

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[Youssef1313]

/backport to rel/3.9

[github-actions]

Started backporting to rel/3.9: https://github.com/microsoft/testfx/actions/runs/15195038006

[Youssef1313]

I think it's too fragile to allow MSTest.TestAdapter netstandard2.0 assembly to be used with MSTest.TestFramework. I'm going to close this PR. The backport was merged already but it doesn't harm as well.