Unity 6.5 / 6000.5.1f1 package mode tests fail with Code Coverage CS0619 errors

[litefeel]

Bug description

game-ci/unity-test-runner@v4 fails when running Unity 6.5 / 6000.5.1f1 tests in package mode. The failure happens during script compilation before test results are produced.

The compile error comes from com.unity.testtools.codecoverage, where TreeView / TreeViewItem obsolete API warnings are emitted as CS0619 errors under Unity 6000.5.1f1.

How to reproduce

Steps to reproduce the behavior:

1. Run game-ci/unity-test-runner@v4 against a Unity package using Unity 6000.5.1f1.
2. Set packageMode: true.
3. Run the tests on an Ubuntu runner.
4. The Run tests step fails during Unity script compilation.

Key GitHub Actions config:

- name: Run tests
  uses: game-ci/unity-test-runner@v4
  env:
    UNITY_LICENSE: ${{ env.UNITY_LICENSE }}
  with:
    projectPath: MyPlugin
    packageMode: true
    unityVersion: 6000.5.1f1
    githubToken: ${{ secrets.GITHUB_TOKEN }}

Observed environment:

• Job name: Test 6000.5.1f1
• Action: game-ci/unity-test-runner@v4
• Resolved action SHA in the log: 0ff419b913a3630032cbe0de48a0099b5a9f0ed9
• Runner image: ubuntu-24.04
• Unity Editor: 6000.5.1f1 (0d9463e84828), branch 6000.5/staging

Relevant log output:

Library/PackageCache/com.unity.testtools.codecoverage@6c0a8bccec22/Editor/CoverageWindow/IncludedAssembliesTreeView.cs(124,36): error CS0619: 'TreeViewItem' is obsolete: 'TreeViewItem is now deprecated. You can likely now use TreeViewItem<int> instead and not think more about it. But if you were using that identifier to store InstanceID data, you should instead opt to upgrade your TreeViews to use TreeViewItem<InstanceID> to get the proper typing.'
Library/PackageCache/com.unity.testtools.codecoverage@6c0a8bccec22/Editor/CoverageWindow/IncludedAssembliesTreeView.cs(12,40): error CS0619: 'TreeView' is obsolete: 'TreeView is now deprecated. You can likely now use TreeView<int> instead and not think more about it. But if you were using that identifier to store InstanceID data, you should instead opt to upgrade your TreeViews to use TreeView<InstanceID> to get the proper typing.'
Library/PackageCache/com.unity.testtools.codecoverage@6c0a8bccec22/Editor/CoverageWindow/IncludedAssembliesTreeView.cs(30,48): error CS0619: 'TreeViewItem' is obsolete: 'TreeViewItem is now deprecated. You can likely now use TreeViewItem<int> instead and not think more about it. But if you were using that identifier to store InstanceID data, you should instead opt to upgrade your TreeViews to use TreeViewItem<InstanceID> to get the proper typing.'
Library/PackageCache/com.unity.testtools.codecoverage@6c0a8bccec22/Editor/CoverageWindow/IncludedAssembliesTreeView.cs(35,28): error CS0619: 'TreeViewItem' is obsolete: 'TreeViewItem is now deprecated. You can likely now use TreeViewItem<int> instead and not think more about it. But if you were using that identifier to store InstanceID data, you should instead opt to upgrade your TreeViews to use TreeViewItem<InstanceID> to get the proper typing.'
*** Tundra build failed
Scripts have compiler errors.
Unexpected exit code 1
The process '/usr/bin/docker' failed with exit code 1

• Expected behavior

unity-test-runner should be able to run package mode tests on Unity 6.5 / 6000.5.1f1, or document/configure a compatible Code Coverage package/version for this Unity release.

Additional details

This appears to be related to compiling com.unity.testtools.codecoverage under Unity 6000.5.1f1, where obsolete TreeView / TreeViewItem API usage is now fatal. Please let me know if there is a recommended workaround for package mode, such as overriding the Code Coverage package version or disabling coverage for Unity 6.5 until the package is compatible.

[frostebite]

This is the code coverage package's own obsolete-API-as-error issue under 6000.5.1f1, not something unity-test-runner compiles itself — but since -enableCodeCoverage was previously unconditional with no opt-out, there was no workaround short of forking. Opened #311 to add a coverageEnabled: false input that skips code coverage instrumentation entirely, which should let package-mode tests run on 6000.5.1f1 until com.unity.testtools.codecoverage fixes its own CS0619 issue upstream.