[perf-improver] Add benchmark coverage for ObjectModelConverters.FixUpTestCase

[github-actions]

Tip

Your pull request is ready to create! 🎉 ✅

Everything is OK—the changes have been pushed to branch perf-assist/objectmodelconverters-fixuptestcase-benchmark-c54b6061feb1bbb0. Please review the changes, including any protected files, before creating the pull request.

Create the pull request

The original pull request description is below.

---

Goal and rationale

ObjectModelConverters.FixUpTestCase (VSTestBridge) runs once per VSTest TestCase during discovery/execution — a genuine per-test hot path for every VSTest-driven run through this bridge. It was previously optimized (2026-08-13, avoiding a LINQ Any(lambda) delegate allocation) but had no dedicated benchmark to guard against future regressions or to serve as a baseline for further optimization.

Approach

• Added InternalsVisibleTo for MSTest.Performance.Benchmarks to Microsoft.Testing.Extensions.VSTestBridge.csproj (matching the existing IVT pattern already used for TestFramework/MSTest.TestAdapter/MSTestAdapter.PlatformServices).
• Added a ProjectReference to VSTestBridge from the benchmarks project.
• Added ObjectModelConvertersBenchmarks.cs, measuring FixUpTestCase on a freshly-constructed TestCase per iteration (via [IterationSetup], since the method mutates the instance).

Performance evidence

Ran via dotnet <benchmarks-dll> --filter "*ObjectModelConverters*" --job short (BenchmarkDotNet, .NET 10, Linux sandbox):

Method	Mean	Allocated
FixUpTestCase	4.626 μs	112 B

This establishes a baseline; the small residual allocation comes from TestCase.SetPropertyValue's dictionary-backed property store, which is out of scope for this change.

Trade-offs

None expected — this is additive benchmark/test-infrastructure code, not a runtime behavior change. No new production dependencies.

Reproducibility

./build.sh -c Release
cd test/Performance/MSTest.Performance.Benchmarks
dotnet run -c Release -f net10.0 --no-build -- --filter "*ObjectModelConverters*" --job short

Test Status

• ./build.sh -c Release succeeded (0 warnings, 0 errors).
• Microsoft.Testing.Extensions.VSTestBridge.UnitTests filtered to ObjectModelConvertersTests (--filter "FullyQualifiedName~ObjectModelConvertersTests"): 25/25 passed.
• dotnet format --verify-no-changes clean for changed files.

---

Note

GitHub Actions is not permitted to create or approve pull requests in this repository.

The changes have been pushed to branch perf-assist/objectmodelconverters-fixuptestcase-benchmark-c54b6061feb1bbb0 and are ready to review.

To fix the permissions issue, go to Settings → Actions → General and enable Allow GitHub Actions to create and approve pull requests. See also: gh-aw FAQ

Show patch preview (37 of 87 lines)

From b3cc00256aaf056893f1fc8c503a6198341dd022 Mon Sep 17 00:00:00 2001
X-GH-AW-Base-Commit: 00b4e2a445a42b8768fdd706e7de778e582fb034
From: "github-actions[bot]" <github-actions[bot]@users.noreply.github.com>
Date: Fri, 18 Sep 2026 13:50:28 +0000
Subject: [PATCH] Add benchmark coverage for
 ObjectModelConverters.FixUpTestCase

FixUpTestCase runs once per VSTest TestCase discovered/executed through
the VSTestBridge (a genuine per-test hot path), and previously had no
dedicated benchmark despite the LINQ-allocation fix made to it earlier.

Adds InternalsVisibleTo from VSTestBridge to MSTest.Performance.Benchmarks
and a ProjectReference to VSTestBridge in the benchmarks project, plus
ObjectModelConvertersBenchmarks.cs measuring FixUpTestCase on a
freshly-constructed TestCase per iteration.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 ...oft.Testing.Extensions.VSTestBridge.csproj |  1 +
 .../MSTest.Performance.Benchmarks.csproj      |  1 +
 .../ObjectModelConvertersBenchmarks.cs        | 29 +++++++++++++++++++
 3 files changed, 31 insertions(+)
 create mode 100644 test/Performance/MSTest.Performance.Benchmarks/ObjectModelConvertersBenchmarks.cs

diff --git a/src/Platform/Microsoft.Testing.Extensions.VSTestBridge/Microsoft.Testing.Extensions.VSTestBridge.csproj b/src/Platform/Microsoft.Testing.Extensions.VSTestBridge/Microsoft.Testing.Extensions.VSTestBridge.csproj
index 2cb7bf5..5239f88 100644
--- a/src/Platform/Microsoft.Testing.Extensions.VSTestBridge/Microsoft.Testing.Extensions.VSTestBridge.csproj
+++ b/src/Platform/Microsoft.Testing.Extensions.VSTestBridge/Microsoft.Testing.Extensions.VSTestBridge.csproj
@@ -22,6 +22,7 @@
   <ItemGroup>
     <InternalsVisibleTo Include="MSTest.TestAdapter" Key="$(VsPublicKey)" />
     <InternalsVisibleTo Include="Microsoft.Testing.Extensions.VSTestBridge.UnitTests" Key="$(VsPublicKey)" />
+    <InternalsVisibleTo Include="MSTest.Performance.Benchmarks" Key="$(VsPublicKey)" />
   </ItemGroup>
 
 
diff --
... (truncated)

Warning

Firewall blocked 2 domains

The following domains were blocked by the firewall during workflow execution:

• github.com
• southcentralus0.in.applicationinsights.azure.com

To allow these domains, add them to the network.allowed list in your workflow frontmatter:

network:
  allowed:
    - defaults
    - "github.com"
    - "southcentralus0.in.applicationinsights.azure.com"

See Network Configuration for more information.

🤖 Automated content by GitHub Copilot. Generated by the Perf Improver workflow. · copilot · auto · 276.2 AIC · ⌖ 9.86 AIC · ⊞ 16K · [◷]( · ◷)
_{Comment /perf-assist to run again}

_{Add this agentic workflow to your repo}

To install this agentic workflow, run

gh aw add githubnext/agentics/workflows/perf-improver.md@main