[Flaky Test] Microsoft.Build.UnitTests.CodeTaskFactoryTests.BuildTaskSimpleCodeFactory_RedirectFrom12

**Flaky-test key** (automated de-duplication — do not edit):
```text
flaky-test-id: Microsoft.Build.UnitTests.CodeTaskFactoryTests.BuildTaskSimpleCodeFactory_RedirectFrom12
```

## Evidence

- **Distinct sources:** 4 (0 PRs, 4 rolling builds on `main`)
- **Rolling build IDs:** [1514373](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1514373), [1517682](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1517682), [1527742](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1527742), [1532844](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1532844)
- **Legs:** FullOnWindows Release
- **Assembly:** `Microsoft.Build.Tasks.UnitTests`
- **First seen:** 2026-07-17 | **Last seen:** 2026-07-30
- **Error hash:** 2f59b830
- **Sample error:** `Assert.True() Failure — Expected: True, Actual: False`

## Action

This test will be quarantined via `[ActiveIssue("")]` (from `Microsoft.DotNet.XUnitV3Extensions`, namespace `Xunit`) until the underlying nondeterminism is fixed. The quarantine pipeline (def 344) will continue gathering pass/fail signal.

**Assembly:** `Microsoft.Build.Tasks.UnitTests`
**Class:** `Microsoft.Build.UnitTests.CodeTaskFactoryTests`
**Method:** `BuildTaskSimpleCodeFactory_RedirectFrom12`
**Source:** `src/Tasks.UnitTests/CodeTaskFactoryTests.cs`

> [!WARNING]
>
> Firewall blocked 2 domains
>
> The following domains were blocked by the firewall during workflow execution:
>
> - `awmgmcpg`
> - `southcentralus0.in.applicationinsights.azure.com`
>> To allow these domains, add them to the `network.allowed` list in your workflow frontmatter:
>
> ```yaml
> network:
> allowed:
> - defaults
> - "awmgmcpg"
> - "southcentralus0.in.applicationinsights.azure.com"
> ```
>
> See [Network Configuration](https://github.github.com/gh-aw/reference/network/) for more information.
>
>

> Generated by [Flaky Test Triage](https://github.com/dotnet/msbuild/actions/runs/30541891245) · sonnet46 · 155.1 AIC · ⌖ 5.48 AIC · ⊞ 14.7K · [◷](https://github.com/search?q=repo%3Adotnet%2Fmsbuild+is%3Aissue+%22gh-aw-workflow-call-id%3A+dotnet%2Fmsbuild%2Fflaky-test-detector.agent%22&type=issues)

Start with src/Tasks.UnitTests/CodeTaskFactoryTests.cs and the BuildTaskSimpleCodeFactory_RedirectFrom12 method, then run the test in the Microsoft.Build.Tasks.UnitTests assembly and compare it with the four listed rolling-build failures. Trace the Assert.True failure and investigate the nondeterminism. Done means the test passes reliably on the FullOnWindows Release leg without relying on quarantine.

Written by the indexing model from the issue text.