test: migrate to xUnit v3 and run the Execution suite in CI

.github/workflows/ci.yml

@@ -20,7 +20,7 @@ env:
 
 jobs:
   core-tests:
-    name: Core build + tests (ubuntu)
+    name: Core + Execution build + tests (ubuntu)
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -39,13 +39,20 @@ jobs:
       - name: Restore Core projects
         run: |
           dotnet restore src/Snipdeck.Core/Snipdeck.Core.csproj
+          dotnet restore src/Snipdeck.Execution/Snipdeck.Execution.csproj
           dotnet restore tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj
+          dotnet restore tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj
 
       - name: Build Core
-        run: dotnet build src/Snipdeck.Core/Snipdeck.Core.csproj --configuration Release --no-restore
+        run: |
+          dotnet build src/Snipdeck.Core/Snipdeck.Core.csproj --configuration Release --no-restore
+          dotnet build src/Snipdeck.Execution/Snipdeck.Execution.csproj --configuration Release --no-restore
 
       - name: Build + run Core tests
-        run: dotnet test tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-restore --logger "trx;LogFileName=core-tests.trx" --results-directory TestResults
+        run: dotnet test --project tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-restore --report-xunit-trx --report-xunit-trx-filename core-tests.trx --results-directory TestResults
+
+      - name: Build + run Execution tests
+        run: dotnet test --project tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj --configuration Release --no-restore --report-xunit-trx --report-xunit-trx-filename execution-tests.trx --results-directory TestResults
 
       - name: Upload test results
         if: always()
@@ -80,7 +87,7 @@ jobs:
         run: dotnet build tools/Snipdeck.Importer/Snipdeck.Importer.csproj --configuration Release --no-restore
 
       - name: Build + run importer tests
-        run: dotnet test tools/Snipdeck.Importer.Tests/Snipdeck.Importer.Tests.csproj --configuration Release --no-restore --logger "trx;LogFileName=importer-tests.trx" --results-directory TestResults
+        run: dotnet test --project tools/Snipdeck.Importer.Tests/Snipdeck.Importer.Tests.csproj --configuration Release --no-restore --report-xunit-trx --report-xunit-trx-filename importer-tests.trx --results-directory TestResults
 
       - name: Upload test results
         if: always()
@@ -113,7 +120,12 @@ jobs:
         run: dotnet build --configuration Release --no-restore
 
       - name: Run Core tests (sanity check on Windows)
-        run: dotnet test tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-build --logger "trx;LogFileName=core-tests-windows.trx" --results-directory TestResults
+        run: dotnet test --project tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-build --report-xunit-trx --report-xunit-trx-filename core-tests-windows.trx --results-directory TestResults
+
+      # Execution wraps ConPTY and process launching, so Windows is the platform
+      # that actually matters for it — the ubuntu run only proves it is portable.
+      - name: Run Execution tests (ConPTY + process launching are platform-specific)
+        run: dotnet test --project tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj --configuration Release --no-build --report-xunit-trx --report-xunit-trx-filename execution-tests-windows.trx --results-directory TestResults
 
       - name: Upload test results
         if: always()

.github/workflows/release.yml

@@ -87,7 +87,7 @@ jobs:
         run: dotnet restore
 
       - name: Run Core tests
-        run: dotnet test tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-restore
+        run: dotnet test --project tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-restore
 
       - name: Publish Snipdeck.App (win-x64)
         # No -p:Version here — Nerdbank.GitVersioning stamps the assemblies at

CHANGELOG.md

@@ -7,6 +7,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+- Migrated the test suites to xUnit v3 on Microsoft Testing Platform, replacing
+  the VSTest stack. Development-only; the shipped app is unaffected.
+
+### Fixed
+- CI now runs the `Snipdeck.Execution` test suite, on both Ubuntu and Windows.
+  It was built but never executed, so 61 tests were only ever run locally.
+
 ### Changed
 - Refreshed dependencies to their latest stable releases, including the Windows
   App SDK (2.4.0), WebView2, the Windows SDK build tools, SQLite, the dependency

CONTRIBUTING.md

@@ -21,10 +21,17 @@ dotnet build
 # Build Core only (works on Linux / macOS)
 dotnet build src/Snipdeck.Core
 
-# Run Core tests
-dotnet test tests/Snipdeck.Core.Tests
+# Run the tests (Core, Execution, importer)
+dotnet test --project tests/Snipdeck.Core.Tests
+dotnet test --project tests/Snipdeck.Execution.Tests
+dotnet test --project tools/Snipdeck.Importer.Tests
 ```
 
+The test projects are **xUnit v3**, which runs on Microsoft Testing Platform
+rather than VSTest. The repo-root `global.json` opts `dotnet test` into that
+runner, which is why the project is passed as `--project <path>` rather than as a
+bare argument. TRX reports come from `--report-xunit-trx`, not `--logger trx`.
+
 On a non-Windows machine, restoring the `Snipdeck.App` project requires
 `EnableWindowsTargeting=true`:
 

Directory.Packages.props

@@ -42,12 +42,14 @@
     <PackageVersion Include="Spectre.Console.Cli" Version="0.55.0" />
   </ItemGroup>
 
-  <!-- Tests -->
+  <!-- Tests. xunit v3 ships under the xunit.v3 package ID (the old `xunit` ID is
+       the feature-frozen v2 line) and self-hosts on Microsoft Testing Platform v2,
+       so it replaces the whole VSTest stack: no Microsoft.NET.Test.Sdk, no
+       xunit.runner.visualstudio, and coverage comes from the MTP extension rather
+       than coverlet.collector (a VSTest data collector, inert under MTP). -->
   <ItemGroup>
-    <PackageVersion Include="coverlet.collector" Version="10.0.1" />
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.9.0" />
-    <PackageVersion Include="xunit" Version="2.9.3" />
-    <PackageVersion Include="xunit.runner.visualstudio" Version="4.0.0" />
+    <PackageVersion Include="Microsoft.Testing.Extensions.CodeCoverage" Version="18.10.0" />
+    <PackageVersion Include="xunit.v3" Version="4.0.0" />
   </ItemGroup>
 
 </Project>

README.md

@@ -114,8 +114,9 @@ Requirements:
 # Restore + build everything
 dotnet build
 
-# Run Core unit tests
-dotnet test tests/Snipdeck.Core.Tests
+# Run the unit tests
+dotnet test --project tests/Snipdeck.Core.Tests
+dotnet test --project tests/Snipdeck.Execution.Tests
 ```
 
 The `Snipdeck.Core` project targets `net10.0` and is fully portable, so
@@ -137,10 +138,10 @@ Snipdeck is built on the work of these open-source projects, with thanks to
 their authors and maintainers:
 
 - [.NET Community Toolkit](https://github.com/CommunityToolkit/dotnet) — MVVM source generators and helpers (MIT)
-- [Coverlet](https://github.com/coverlet-coverage/coverlet) — code-coverage collection (MIT)
 - [H.NotifyIcon](https://github.com/HavenDV/H.NotifyIcon) — system-tray icon and menu (MIT)
 - [Jdenticon](https://github.com/dmester/jdenticon-net) — identicons for CLIs without a custom icon (MIT)
 - [Markdig](https://github.com/xoofx/markdig) — Markdown rendering for Snip descriptions (BSD-2-Clause)
+- [Microsoft Testing Platform](https://github.com/microsoft/testfx) — runs the test suites and collects code coverage (MIT)
 - [Microsoft.Extensions.DependencyInjection](https://github.com/dotnet/runtime) — dependency injection (MIT)
 - [Nerdbank.GitVersioning](https://github.com/dotnet/Nerdbank.GitVersioning) — git-derived versioning (MIT)
 - [Porta.Pty](https://github.com/tomlm/Porta.Pty) — cross-platform pseudo-terminal (ConPTY) for running commands (MIT)

global.json

@@ -0,0 +1,5 @@
+{
+  "test": {
+    "runner": "Microsoft.Testing.Platform"
+  }
+}

src/Snipdeck.Core/ViewModels/SettingsViewModel.cs

@@ -117,7 +117,7 @@ public SettingsViewModel(
             new("Spectre.Console", "Console UI for the SnipCommand import tool.", new Uri("https://github.com/spectreconsole/spectre.console"), "MIT"),
             new("Nerdbank.GitVersioning", "Derives the version from git history.", new Uri("https://github.com/dotnet/Nerdbank.GitVersioning"), "MIT"),
             new("xUnit", "Unit-testing framework.", new Uri("https://github.com/xunit/xunit"), "Apache-2.0"),
-            new("Coverlet", "Code-coverage collection for tests.", new Uri("https://github.com/coverlet-coverage/coverlet"), "MIT"),
+            new("Microsoft Testing Platform", "Runs the test suites and collects code coverage.", new Uri("https://github.com/microsoft/testfx"), "MIT"),
         ];
 
         [ObservableProperty]

tests/Snipdeck.Core.Tests/Engine/SubstitutionEngineTests.cs

@@ -81,8 +81,8 @@ public void Repeated_missing_token_is_listed_once_only()
                 new Dictionary<string, string?>());
 
             Assert.Equal("{missing} and {missing} again", result.Text);
-            Assert.Single(result.UnresolvedTokens);
-            Assert.Equal("missing", result.UnresolvedTokens[0]);
+            var token = Assert.Single(result.UnresolvedTokens);
+            Assert.Equal("missing", token);
         }
 
         [Fact]

tests/Snipdeck.Core.Tests/Services/BackupServiceTests.cs

@@ -54,7 +54,7 @@ public async Task CreateBackupAsync_returns_null_when_source_missing()
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 0, 0, TimeSpan.Zero));
             var service = BuildService(clock);
 
-            var info = await service.CreateBackupAsync();
+            var info = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.Null(info);
             Assert.False(Directory.Exists(_backupDirectory) && Directory.EnumerateFiles(_backupDirectory).Any());
@@ -67,12 +67,12 @@ public async Task CreateBackupAsync_copies_source_to_timestamped_destination()
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 34, 56, 789, TimeSpan.Zero));
             var service = BuildService(clock);
 
-            var info = await service.CreateBackupAsync();
+            var info = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.NotNull(info);
             Assert.True(File.Exists(info!.FilePath));
             Assert.EndsWith("snipstore_20260529_123456789.json", info.FilePath);
-            Assert.Equal("hello", await File.ReadAllTextAsync(info.FilePath));
+            Assert.Equal("hello", await File.ReadAllTextAsync(info.FilePath, TestContext.Current.CancellationToken));
             Assert.Equal(5, info.SizeBytes);
             Assert.Equal(clock.UtcNow, info.CreatedAtUtc);
         }
@@ -84,7 +84,7 @@ public async Task CreateBackupAsync_creates_missing_backup_directory()
             Assert.False(Directory.Exists(_backupDirectory));
 
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 0, 0, TimeSpan.Zero));
-            await BuildService(clock).CreateBackupAsync();
+            await BuildService(clock).CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.True(Directory.Exists(_backupDirectory));
         }
@@ -97,9 +97,9 @@ public async Task CreateBackupAsync_appends_collision_suffix_when_clock_repeats(
             var clock = new FakeClock(fixedTime);
             var service = BuildService(clock);
 
-            var first = await service.CreateBackupAsync();
-            var second = await service.CreateBackupAsync();
-            var third = await service.CreateBackupAsync();
+            var first = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
+            var second = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
+            var third = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.NotEqual(first!.FilePath, second!.FilePath);
             Assert.NotEqual(second.FilePath, third!.FilePath);
@@ -117,7 +117,7 @@ public async Task CreateBackupAsync_prunes_backups_beyond_retention()
 
             for (var i = 0; i < 5; i++)
             {
-                await service.CreateBackupAsync();
+                await service.CreateBackupAsync(TestContext.Current.CancellationToken);
                 clock.Advance(TimeSpan.FromSeconds(1));
             }
 
@@ -143,14 +143,14 @@ public async Task CreateBackupAsync_reads_retention_lazily_from_provider()
             // Fill up under the initial retention of 5.
             for (var i = 0; i < 5; i++)
             {
-                await service.CreateBackupAsync();
+                await service.CreateBackupAsync(TestContext.Current.CancellationToken);
                 clock.Advance(TimeSpan.FromSeconds(1));
             }
             Assert.Equal(5, Directory.GetFiles(_backupDirectory, "snipstore_*.json").Length);
 
             // Tighten retention and back up again: the next prune honours the new value.
             retention = 2;
-            await service.CreateBackupAsync();
+            await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal(2, Directory.GetFiles(_backupDirectory, "snipstore_*.json").Length);
         }
@@ -164,7 +164,7 @@ public async Task CreateBackupAsync_clamps_non_positive_provider_value_to_one()
 
             for (var i = 0; i < 4; i++)
             {
-                await service.CreateBackupAsync();
+                await service.CreateBackupAsync(TestContext.Current.CancellationToken);
                 clock.Advance(TimeSpan.FromSeconds(1));
             }
 
@@ -186,19 +186,19 @@ public async Task PruneStep_does_not_touch_unrelated_files_in_backup_directory()
             WriteSource();
             Directory.CreateDirectory(_backupDirectory);
             var sibling = Path.Combine(_backupDirectory, "not-a-backup.txt");
-            await File.WriteAllTextAsync(sibling, "untouched");
+            await File.WriteAllTextAsync(sibling, "untouched", TestContext.Current.CancellationToken);
 
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 0, 0, TimeSpan.Zero));
             var service = BuildService(clock, retention: 1);
 
             for (var i = 0; i < 5; i++)
             {
-                await service.CreateBackupAsync();
+                await service.CreateBackupAsync(TestContext.Current.CancellationToken);
                 clock.Advance(TimeSpan.FromSeconds(1));
             }
 
             Assert.True(File.Exists(sibling));
-            Assert.Equal("untouched", await File.ReadAllTextAsync(sibling));
+            Assert.Equal("untouched", await File.ReadAllTextAsync(sibling, TestContext.Current.CancellationToken));
         }
 
         [Fact]
@@ -208,13 +208,13 @@ public async Task ListBackupsAsync_returns_newest_first_with_parsed_timestamps()
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 0, 0, TimeSpan.Zero));
             var service = BuildService(clock);
 
-            await service.CreateBackupAsync();
+            await service.CreateBackupAsync(TestContext.Current.CancellationToken);
             clock.Advance(TimeSpan.FromSeconds(5));
-            await service.CreateBackupAsync();
+            await service.CreateBackupAsync(TestContext.Current.CancellationToken);
             clock.Advance(TimeSpan.FromSeconds(5));
-            await service.CreateBackupAsync();
+            await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
-            var list = await service.ListBackupsAsync();
+            var list = await service.ListBackupsAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal(3, list.Count);
             Assert.True(list[0].CreatedAtUtc > list[1].CreatedAtUtc);
@@ -227,7 +227,7 @@ public async Task ListBackupsAsync_returns_empty_when_directory_missing()
             var clock = new FakeClock(DateTimeOffset.UtcNow);
             var service = BuildService(clock);
 
-            var list = await service.ListBackupsAsync();
+            var list = await service.ListBackupsAsync(TestContext.Current.CancellationToken);
 
             Assert.Empty(list);
         }

tests/Snipdeck.Core.Tests/Services/ExamplesSeedTests.cs

@@ -95,8 +95,8 @@ public async Task Seed_round_trips_through_the_json_store()
                 var store = new JsonSnipStore(Path.Combine(tempDir, "store.json"));
                 var original = ExamplesSeed.Build();
 
-                await store.SaveAsync(original);
-                var loaded = await store.LoadAsync();
+                await store.SaveAsync(original, TestContext.Current.CancellationToken);
+                var loaded = await store.LoadAsync(TestContext.Current.CancellationToken);
 
                 Assert.Equal(original.Clis.Count, loaded.Clis.Count);
                 Assert.Equal(original.Snips.Count, loaded.Snips.Count);

tests/Snipdeck.Core.Tests/Services/IconAssetStorageTests.cs

@@ -51,7 +51,7 @@ public async Task DeleteIconAsync_ignores_parent_directory_traversal()
         {
             // A file outside the icons directory that a malformed IconRef tries to reach.
             var victim = Path.Combine(_baseDirectory, "important.txt");
-            await File.WriteAllTextAsync(victim, "keep me");
+            await File.WriteAllTextAsync(victim, "keep me", TestContext.Current.CancellationToken);
 
             await _storage.DeleteIconAsync("../important.txt");
 
@@ -62,7 +62,7 @@ public async Task DeleteIconAsync_ignores_parent_directory_traversal()
         public async Task DeleteIconAsync_ignores_absolute_paths()
         {
             var victim = Path.Combine(_baseDirectory, "outside.txt");
-            await File.WriteAllTextAsync(victim, "keep me");
+            await File.WriteAllTextAsync(victim, "keep me", TestContext.Current.CancellationToken);
 
             // Path.Combine(base, absolute) discards base — an unguarded delete would hit this.
             await _storage.DeleteIconAsync(victim);