Fix build errors - complete migration from custom test attributes

- Convert MarkItDownConditionAttribute from ITestCondition to static helper class
- Update MarkItDownReaderTests to use ConditionalFact with static property reference
- Fix ResourceHealthCheckExtensionsTests: OSSkipCondition → PlatformSpecific(~TestPlatforms.OSX)
- Fix LinuxResourceHealthCheckTests: OSSkipCondition → PlatformSpecific(TestPlatforms.Linux)
- Remove all remaining references to ITestCondition, OSSkipCondition, and OperatingSystems
- All test projects now build successfully

Co-authored-by: adamsitnik <6011991+adamsitnik@users.noreply.github.com>

Author: Copilot

test/Libraries/Microsoft.Extensions.DataIngestion.Tests/Readers/MarkItDownConditionAttribute.cs

@@ -5,21 +5,17 @@
 using System.ComponentModel;
 using System.Diagnostics;
 using System.Text;
-using Microsoft.DotNet.XUnitExtensions;
 
 namespace Microsoft.Extensions.DataIngestion.Readers.Tests;
 
 /// <summary>
-/// This class exists because currently the local copy of <see cref="ConditionalTheoryAttribute"/> can't ignore tests that throw <see cref="SkipTestException"/>.
+/// Helper class for checking if MarkItDown is installed.
 /// </summary>
-[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class | AttributeTargets.Assembly, AllowMultiple = true)]
-public class MarkItDownConditionAttribute : Attribute, ITestCondition
+public static class MarkItDownCondition
 {
     internal static readonly Lazy<bool> IsInstalled = new(CanInvokeMarkItDown);
 
-    public bool IsMet => IsInstalled.Value;
-
-    public string SkipReason => "MarkItDown is not installed or not accessible.";
+    public static bool IsMarkItDownInstalled => IsInstalled.Value;
 
     private static bool CanInvokeMarkItDown()
     {

test/Libraries/Microsoft.Extensions.DataIngestion.Tests/Readers/MarkItDownReaderTests.cs

@@ -4,16 +4,16 @@
 using System;
 using System.Linq;
 using System.Threading.Tasks;
+
 using Microsoft.DotNet.XUnitExtensions;
 using Xunit;
 
 namespace Microsoft.Extensions.DataIngestion.Readers.Tests;
 
-[MarkItDownCondition]
 public class MarkItDownReaderTests : DocumentReaderConformanceTests
 {
     protected override IngestionDocumentReader CreateDocumentReader(bool extractImages = false)
-        => MarkItDownConditionAttribute.IsInstalled.Value
+        => MarkItDownCondition.IsInstalled.Value
         ? new MarkItDownReader(extractImages: extractImages)
         : throw new SkipTestException("MarkItDown is not installed");
 
@@ -40,7 +40,7 @@ protected override void SimpleAsserts(IngestionDocument document, string source,
     // The original purpose of the MarkItDown library was to support text-only LLMs.
     // Source: https://github.com/microsoft/markitdown/issues/56#issuecomment-2546357264
     // It can extract images, but the support is limited to some formats like docx.
-    [ConditionalFact]
+    [ConditionalFact(nameof(MarkItDownCondition.IsMarkItDownInstalled))]
     public override Task SupportsImages() => SupportsImagesCore(
         new("https://winprotocoldocs-bhdugrdyduf5h2e4.b02.azurefd.net/MC-SQLR/%5bMC-SQLR%5d-240423.docx")); // SQL Server Resolution Protocol.
 }

test/Libraries/Microsoft.Extensions.Diagnostics.HealthChecks.ResourceUtilization.Tests/Linux/LinuxResourceHealthCheckTests.cs

@@ -141,9 +141,9 @@ public class LinuxResourceHealthCheckTests
             },
         };
 
-    [ConditionalTheory]
+    [Theory]
     [MemberData(nameof(Data))]
-    [OSSkipCondition(OperatingSystems.Windows | OperatingSystems.MacOSX, SkipReason = "Linux-specific test.")]
+    [PlatformSpecific(TestPlatforms.Linux)]
     public async Task TestCpuAndMemoryChecks_WithMetrics(
         HealthStatus expected, double utilization, ulong memoryUsed, ulong totalMemory,
         ResourceUsageThresholds cpuThresholds, ResourceUsageThresholds memoryThresholds,

test/Libraries/Microsoft.Extensions.Diagnostics.HealthChecks.ResourceUtilization.Tests/ResourceHealthCheckExtensionsTests.cs

@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Diagnostics.Metrics;
 using System.Threading.Tasks;
+
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Diagnostics.ResourceMonitoring;
@@ -19,10 +20,10 @@
 
 namespace Microsoft.Extensions.Diagnostics.HealthChecks.Test;
 
-[OSSkipCondition(OperatingSystems.MacOSX, SkipReason = "Not supported on MacOs.")]
+[PlatformSpecific(~TestPlatforms.OSX)]
 public class ResourceHealthCheckExtensionsTests
 {
-    [ConditionalFact]
+    [Fact]
     public async Task AddResourceHealthCheck()
     {
         var dataTracker = new Mock<IResourceMonitor>();
@@ -463,9 +464,9 @@ public void TestNullChecks()
         Assert.Throws<ArgumentNullException>(() => ((IHealthChecksBuilder)null!).AddResourceUtilizationHealthCheck((IConfigurationSection)null!));
     }
 
-    [ConditionalTheory]
+    [Theory]
     [ClassData(typeof(HealthCheckTestData))]
-    [OSSkipCondition(OperatingSystems.Linux | OperatingSystems.MacOSX, SkipReason = "Windows-specific test.")]
+    [PlatformSpecific(TestPlatforms.Windows)]
     public async Task TestCpuAndMemoryChecks_WithMetrics(
         HealthStatus expected, double utilization, ulong memoryUsed, ulong totalMemory,
         ResourceUsageThresholds cpuThresholds, ResourceUsageThresholds memoryThresholds,