[clr-ios] Enable Text.Json tests on CoreCLR Apple mobile

[Copilot]

Description

This PR enables System.Text.Json.Tests that were excluded across all CoreCLR Apple mobile targets.

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Tagging subscribers to 'os-ios': @vitek-karas, @kotlarmilos, @steveisok, @akoeplinger
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[kotlarmilos]

/azp run runtime-ioslike

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[Copilot]

Pull request overview

This PR re-enables System.Collections.Concurrent.Tests and System.Text.Json.Tests for CoreCLR Apple mobile test runs by removing their project-level exclusions, while adding a targeted [ActiveIssue] skip for a known-failing ConcurrentDictionary test on CoreCLR Apple mobile.

Changes:

• Removed CoreCLR Apple mobile exclusions for System.Collections.Concurrent.Tests and System.Text.Json.Tests from src/libraries/tests.proj.
• Added an [ActiveIssue] annotation to skip a specific ConcurrentDictionary theory on IsAppleMobile && IsCoreCLR.

Show a summary per file

File	Description
src/libraries/tests.proj	Stops excluding Concurrent and Text.Json test projects for CoreCLR Apple mobile targets, allowing them to run again.
src/libraries/System.Collections.Concurrent/tests/ConcurrentDictionary/ConcurrentDictionary.Generic.Tests.cs	Adds a targeted active-issue skip for a specific failing test on CoreCLR Apple mobile.

Copilot's findings

• Files reviewed: 2/2 changed files
• Comments generated: 0

[kotlarmilos]

/azp run runtime-ioslike

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[kotlarmilos]

/azp run runtime-ioslike

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[Copilot]

Copilot's findings

• Files reviewed: 1/1 changed files
• Comments generated: 0 new

[github-actions]

🤖 Copilot Code Review — PR #127497

Note

This review was generated by GitHub Copilot.

Holistic Assessment

Motivation: The PR removes System.Text.Json.Tests from the project exclusion list for CoreCLR Apple mobile targets. The test was previously excluded due to timeouts, and the commit history shows the author iteratively verified that this specific test suite now passes within acceptable time limits while keeping other timeout-prone tests (Concurrent, HttpListener) excluded.

Approach: Removing the exclusion line from the TargetsAppleMobile && CoreCLR && !NativeAOT ItemGroup is the correct and minimal approach to re-enable these tests. The iterative commit history demonstrates due diligence — timeouts were bumped, tests were re-enabled in batches, and tests that still timed out were re-excluded.

Summary: ✅ LGTM. This is a well-scoped, minimal infrastructure change that re-enables a previously-excluded test suite. The commit history shows the author validated that System.Text.Json.Tests passes on CoreCLR Apple mobile while appropriately keeping other problematic test suites excluded. CI will provide final confirmation.

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Detailed Findings

✅ Change is correct and well-scoped

The net diff removes a single ProjectExclusions line for System.Text.Json.Tests.csproj from the ItemGroup conditioned on '$(TargetsAppleMobile)' == 'true' and '$(RuntimeFlavor)' == 'CoreCLR' and '$(UseNativeAOTRuntime)' != 'true'. The surrounding exclusions for System.Collections.Concurrent.Tests and System.Net.HttpListener.Tests (which still timeout) are appropriately retained under the <!-- Timeouts --> comment.

✅ Commit history shows iterative validation

The PR went through multiple iterations: initially re-enabling several test suites and bumping timeouts, then reverting changes for tests that still timed out, arriving at the focused change of only enabling Text.Json tests. This demonstrates proper validation rather than a speculative change.

💡 Minor observation — no tracking issue linked

The "Timeouts" exclusions do not reference a specific tracking issue (unlike the <!-- https://github.com/dotnet/runtime/issues/124344 --> exclusions above). Consider adding a brief comment or linking to a tracking issue for the remaining timeout exclusions so future contributors know when to revisit them. This is non-blocking and could be addressed separately.

Generated by Code Review for issue #127497 · ◷