refactor: use non-static OS selector in tests

Tests/Helpers/Testably.Abstractions.TestHelpers/FileSystemTestBase.cs

@@ -17,13 +17,17 @@ public abstract class FileSystemTestBase<TFileSystem>
 	where TFileSystem : IFileSystem
 {
 	public abstract string BasePath { get; }
+	public Test Test { get; }
 	public TFileSystem FileSystem { get; }
 	public ITimeSystem TimeSystem { get; }
 
 	// ReSharper disable once UnusedMember.Global
-	protected FileSystemTestBase(TFileSystem fileSystem,
+	protected FileSystemTestBase(
+		Test test,
+		TFileSystem fileSystem,
 		ITimeSystem timeSystem)
 	{
+		Test = test;
 		FileSystem = fileSystem;
 		TimeSystem = timeSystem;
 

Tests/Helpers/Testably.Abstractions.TestHelpers/Test.cs

@@ -1,72 +1,66 @@
-using System.IO.Abstractions;
-using System.Runtime.InteropServices;
-using Xunit;
-
-namespace Testably.Abstractions.TestHelpers;
-
-public static class Test
-{
-	private static bool? _isNetFramework;
-
-	public static bool IsNetFramework
-	{
-		get
-		{
-			_isNetFramework ??= RuntimeInformation
-				.FrameworkDescription.StartsWith(".NET Framework");
-			return _isNetFramework.Value;
-		}
-	}
-
-	public static bool RunsOnLinux
-		=> RuntimeInformation.IsOSPlatform(OSPlatform.Linux);
-
-	public static bool RunsOnMac
-		=> RuntimeInformation.IsOSPlatform(OSPlatform.OSX);
-
-	public static bool RunsOnWindows
-		=> RuntimeInformation.IsOSPlatform(OSPlatform.Windows);
-
-	public static bool IsNet7OrGreater
+using System.IO.Abstractions;
+using System.Runtime.InteropServices;
+using Xunit;
+
+namespace Testably.Abstractions.TestHelpers;
+
+public class Test
+{
+	public static bool IsNet7OrGreater
 #if NET7_0_OR_GREATER
-		=> true;
-#else
-		=> false;
-#endif
-
-	public static void SkipBrittleTestsOnRealFileSystem(
-		IFileSystem fileSystem, bool condition = true)
-	{
-		Skip.If(fileSystem is RealFileSystem && condition,
-			"Brittle tests are skipped on the real file system.");
-	}
-
-	public static void SkipBrittleTestsOnRealTimeSystem(
-		ITimeSystem timeSystem, bool condition = true)
-	{
-		Skip.If(timeSystem is RealTimeSystem && condition,
-			"Brittle tests are skipped on the real time system.");
-	}
-
-	public static void SkipIfLongRunningTestsShouldBeSkipped(IFileSystem fileSystem)
-	{
-#if DEBUG && !INCLUDE_LONGRUNNING_TESTS_ALSO_IN_DEBUG_MODE
-		Skip.If(fileSystem is RealFileSystem,
-			"Long-Running tests are skipped in DEBUG mode unless the build constant 'INCLUDE_LONG_RUNNING_TESTS_ALSO_IN_DEBUG_MODE' is set.");
-#endif
-		// ReSharper disable once CommentTypo
-		// Do nothing when in release mode or `INCLUDE_LONGRUNNING_TESTS_ALSO_IN_DEBUG_MODE` is set
-	}
-
-	public static void SkipIfTestsOnRealFileSystemShouldBeSkipped(IFileSystem fileSystem)
-	{
+		=> true;
+#else
+		=> false;
+#endif
+	public bool IsNetFramework { get; }
+
+	public bool RunsOnLinux { get; }
+
+	public bool RunsOnMac { get; }
+
+	public bool RunsOnWindows { get; }
+
+	public Test()
+	{
+		RunsOnLinux = RuntimeInformation.IsOSPlatform(OSPlatform.Linux);
+		RunsOnMac = RuntimeInformation.IsOSPlatform(OSPlatform.OSX);
+		RunsOnWindows = RuntimeInformation.IsOSPlatform(OSPlatform.Windows);
+		IsNetFramework = RuntimeInformation.FrameworkDescription.StartsWith(".NET Framework");
+	}
+
+	public static void SkipBrittleTestsOnRealFileSystem(
+		IFileSystem fileSystem, bool condition = true)
+	{
+		Skip.If(fileSystem is RealFileSystem && condition,
+			"Brittle tests are skipped on the real file system.");
+	}
+
+	public static void SkipBrittleTestsOnRealTimeSystem(
+		ITimeSystem timeSystem, bool condition = true)
+	{
+		Skip.If(timeSystem is RealTimeSystem && condition,
+			"Brittle tests are skipped on the real time system.");
+	}
+
+	public static void SkipIfLongRunningTestsShouldBeSkipped(IFileSystem fileSystem)
+	{
+#if DEBUG && !INCLUDE_LONGRUNNING_TESTS_ALSO_IN_DEBUG_MODE
+		Skip.If(fileSystem is RealFileSystem,
+			"Long-Running tests are skipped in DEBUG mode unless the build constant 'INCLUDE_LONG_RUNNING_TESTS_ALSO_IN_DEBUG_MODE' is set.");
+#endif
+		// ReSharper disable once CommentTypo
+		// Do nothing when in release mode or `INCLUDE_LONGRUNNING_TESTS_ALSO_IN_DEBUG_MODE` is set
+	}
+
+	public static void SkipIfTestsOnRealFileSystemShouldBeSkipped(IFileSystem fileSystem)
+	{
 #if NCRUNCH
-		Skip.If(fileSystem is RealFileSystem, "NCrunch should not test the real file system.");
-#endif
+		Skip.If(fileSystem is RealFileSystem, "NCrunch should not test the real file system.");
+#endif
 #if DEBUG && SKIP_TESTS_ON_REAL_FILESYSTEM
 		Skip.If(fileSystem is RealFileSystem,
-			"Tests against real FileSystem are skipped in DEBUG mode with the build constant 'SKIP_TESTS_ON_REAL_FILESYSTEM'.");
-#endif
-		// Do nothing when in release mode or `SKIP_TESTS_ON_REAL_FILESYSTEM` is not set
-	}
+			"Tests against real FileSystem are skipped in DEBUG mode with the build constant 'SKIP_TESTS_ON_REAL_FILESYSTEM'.");
+#endif
+		// Do nothing when in release mode or `SKIP_TESTS_ON_REAL_FILESYSTEM` is not set
+	}
 }

Tests/Helpers/Testably.Abstractions.Tests.SourceGenerator/ClassGenerators/FileSystemClassGenerator.cs

@@ -21,8 +21,8 @@ namespace {@class.Namespace}
 {{
 	public abstract partial class {@class.Name}<TFileSystem>
 	{{
-		protected {@class.Name}(TFileSystem fileSystem, ITimeSystem timeSystem)
-			: base(fileSystem, timeSystem)
+		protected {@class.Name}(Test test, TFileSystem fileSystem, ITimeSystem timeSystem)
+			: base(test, fileSystem, timeSystem)
 		{{
 		}}
 	}}
@@ -43,6 +43,7 @@ public MockFileSystemTests() : this(new MockFileSystem())
 		}}
 
 		private MockFileSystemTests(MockFileSystem mockFileSystem) : base(
+			new Test(),
 			mockFileSystem,
 			mockFileSystem.TimeSystem)
 		{{
@@ -70,7 +71,7 @@ public sealed class RealFileSystemTests : {@class.Name}<RealFileSystem>, IDispos
 		private readonly IDirectoryCleaner _directoryCleaner;
 
 		public RealFileSystemTests(ITestOutputHelper testOutputHelper)
-			: base(new RealFileSystem(), new RealTimeSystem())
+			: base(new Test(), new RealFileSystem(), new RealTimeSystem())
 		{{
 			_directoryCleaner = FileSystem
 			   .SetCurrentDirectoryToEmptyTemporaryDirectory($""{@class.Namespace}{{FileSystem.Path.DirectorySeparatorChar}}{@class.Name}-"", testOutputHelper.WriteLine);

Tests/Testably.Abstractions.Tests/FileSystem/Directory/CreateDirectoryTests.cs

@@ -69,7 +69,7 @@ public void CreateDirectory_FileWithSameNameAlreadyExists_ShouldThrowIOException
 	[SkippableFact]
 	public void CreateDirectory_Root_ShouldNotThrowException()
 	{
-		string path = FileTestHelper.RootDrive();
+		string path = FileTestHelper.RootDrive(Test);
 		FileSystem.Directory.CreateDirectory(path);
 
 		Exception? exception = Record.Exception(() =>
@@ -313,9 +313,8 @@ public void CreateDirectory_TrailingDirectorySeparator_ShouldNotBeTrimmed(
 		result.Name.Should().Be(expectedName.TrimEnd(
 			FileSystem.Path.DirectorySeparatorChar,
 			FileSystem.Path.AltDirectorySeparatorChar));
-		result.FullName.Should().Be(System.IO.Path.Combine(BasePath, expectedName
-			.Replace(FileSystem.Path.AltDirectorySeparatorChar,
-				FileSystem.Path.DirectorySeparatorChar)));
+		result.FullName.Should().Be($"{BasePath}{FileSystem.Path.DirectorySeparatorChar}{expectedName}"
+			.Replace(FileSystem.Path.AltDirectorySeparatorChar, FileSystem.Path.DirectorySeparatorChar));
 		FileSystem.Should().HaveDirectory(nameWithSuffix);
 	}
 #endif