engine-tests.yml

name: Engine.Tests

# F7-07: the engine's namespace / overload-resolution guard rail, plus the 11-TFM build.
#
# `paths` is kept identical between `push` and `pull_request` and always lists `build/**`, for the
# same reason multi-tests.yml documents: every src project imports build/common.props, which pulls
# in build/version.props, build/package.props and build/misc.props, so a props-only change still
# changes what this job builds.
on:
  push:
    branches: [ dev, master ]
    paths:
      - 'src/DotNetCore.Collections/**'
      - 'tests/DotNetCore.Collections.Tests/**'
      - 'tests/DotNetCore.Collections.FrameworkProbe/**'
      - 'sample/Sample.Engine/**'
      - 'scripts/Check-EngineNamespace.ps1'
      - 'build/**'
      - '.github/workflows/engine-tests.yml'
  pull_request:
    paths:
      - 'src/DotNetCore.Collections/**'
      - 'tests/DotNetCore.Collections.Tests/**'
      - 'tests/DotNetCore.Collections.FrameworkProbe/**'
      - 'sample/Sample.Engine/**'
      - 'scripts/Check-EngineNamespace.ps1'
      - 'build/**'
      - '.github/workflows/engine-tests.yml'

env:
  DOTNET_CLI_TELEMETRY_OPTOUT: 1
  DOTNET_NOLOGO: 1

jobs:
  engine:
    runs-on: windows-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0 # SourceLink needs full history for deterministic build

      - name: Setup .NET
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: 10.0.x

      - name: Namespace governance (F7-07)
        # The source-level half of the R7-05 guard. Nothing under src/DotNetCore.Collections may
        # declare a namespace outside DotNetCore.Collections: declaring an extension method under
        # System.Linq is the one way the engine could inject itself into the BCL's own namespace and
        # hand a consumer CS0121 from a plain `using System.Linq;`. A source scan rather than a
        # reflection test, so declarations the current TFM compiles away are still seen.
        # The API-level half runs in the Test step below (NamespaceGovernanceTests).
        run: pwsh -NoProfile -ExecutionPolicy Bypass -File scripts/Check-EngineNamespace.ps1

      - name: Build (11 TFMs)
        run: dotnet build src/DotNetCore.Collections/DotNetCore.Collections.csproj -c Release

      - name: Pack (verify package generation incl. snupkg)
        # F7-16: the engine ships as its own NuGet package. The pack is verified here for
        # the same reason paginable-tests.yml verifies its own -- a packaging regression
        # (a missing TFM asset, a missing symbol package) should fail CI, not the release.
        run: dotnet pack src/DotNetCore.Collections/DotNetCore.Collections.csproj -c Release --no-build

      - name: Build the overload-resolution sample and the framework probe
        # Built once here and executed below, rather than with `dotnet run`: the probe targets the
        # four .NET Framework generations, which `dotnet exec` cannot host, so the pair is run the
        # same way in both cases — build, then launch the artefact.
        run: |
          dotnet build sample/Sample.Engine/Sample.Engine.csproj -c Release
          dotnet build tests/DotNetCore.Collections.FrameworkProbe/DotNetCore.Collections.FrameworkProbe.csproj -c Release

      - name: Overload resolution, no BCL twin (F7-07)
        # net8.0 is the last target where System.Linq.Enumerable has no Index at all (.NET 9 added
        # it), so the engine's Index is the only candidate and the dual `using` is trivially safe.
        run: dotnet exec sample/Sample.Engine/bin/Release/net8.0/Sample.Engine.dll

      - name: Overload resolution, BCL twin present (F7-07)
        # net10.0 is where the twin exists. The same file must still compile — the engine's Index is
        # declared on the exact receiver type while the BCL's needs an interface conversion, and the
        # better conversion wins — and a bare T[] must still bind to the BCL's, because the engine
        # declares no conversion from T[] to its wrapper.
        run: dotnet exec sample/Sample.Engine/bin/Release/net10.0/Sample.Engine.dll

      - name: Test
        run: dotnet test tests/DotNetCore.Collections.Tests/DotNetCore.Collections.Tests.csproj -c Release

      - name: Framework probe, net451 / net461 / net47 / net48
        # The four .NET Framework generations the xunit stack cannot reach (Microsoft.NET.Test.Sdk
        # needs net462 or newer), yet the list arm rests on the field layout of List<T> on exactly
        # those generations. Runs all four rather than stopping at the first failure, so one CI run
        # reports the whole generation matrix.
        shell: pwsh
        run: |
          $failed = @()
          foreach ($tfm in @('net451', 'net461', 'net47', 'net48')) {
            $probe = "tests/DotNetCore.Collections.FrameworkProbe/bin/Release/$tfm/DotNetCore.Collections.FrameworkProbe.exe"
            Write-Host "--- probe $tfm ---"
            & $probe
            if ($LASTEXITCODE -ne 0) { $failed += $tfm }
          }
          if ($failed.Count -gt 0) {
            Write-Host "probe failed on: $($failed -join ', ')"
            exit 1
          }