From 7452c02b119c4c87621569893a1cc927b7b6f75e Mon Sep 17 00:00:00 2001
From: Stuart Turner <stuart@turner-isageek.com>
Date: Mon, 29 Jul 2024 13:40:07 -0500
Subject: [PATCH] Add CA1036 Suppressor

---
 .../Suppressors/CA1036ComparisonSuppressor.cs | 57 +++++++++++++++++
 tests/AnalyzerTests/CA1036SuppressionTests.cs | 64 +++++++++++++++++++
 2 files changed, 121 insertions(+)
 create mode 100644 src/Vogen/Suppressors/CA1036ComparisonSuppressor.cs
 create mode 100644 tests/AnalyzerTests/CA1036SuppressionTests.cs

diff --git a/src/Vogen/Suppressors/CA1036ComparisonSuppressor.cs b/src/Vogen/Suppressors/CA1036ComparisonSuppressor.cs
new file mode 100644
index 0000000000..da5858b8b3
--- /dev/null
+++ b/src/Vogen/Suppressors/CA1036ComparisonSuppressor.cs
@@ -0,0 +1,57 @@
+using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Diagnostics;
+
+namespace Vogen.Suppressors;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp)]
+[SuppressMessage("ReSharper", "InconsistentNaming")]
+public sealed class CA1036ComparisonSuppressor : DiagnosticSuppressor
+{
+    private static readonly SuppressionDescriptor _suppressIComparableWarning = new(
+        id: "VOGS0003",
+        suppressedDiagnosticId: "CA1036",
+        justification: "Suppress CA1036 on value objects.");
+
+    // ReSharper disable once UseCollectionExpression
+    public override ImmutableArray<SuppressionDescriptor> SupportedSuppressions =>
+        ImmutableArray.Create(_suppressIComparableWarning);
+
+    public override void ReportSuppressions(SuppressionAnalysisContext context)
+    {
+        var attributeSymbol = context.Compilation.GetBestTypeByMetadataName("Vogen.ValueObjectAttribute");
+
+        if (attributeSymbol is null)
+        {
+            return;
+        }
+
+        foreach (var diagnostic in context.ReportedDiagnostics)
+        {
+            ProcessDiagnostic(context, diagnostic);
+        }
+    }
+
+    private static void ProcessDiagnostic(SuppressionAnalysisContext context, Diagnostic diagnostic)
+    {
+        var node = diagnostic.TryFindNode(context.CancellationToken);
+
+        if (node is null)
+        {
+            return;
+        }
+
+        var semanticModel = context.GetSemanticModel(node.SyntaxTree);
+
+        var valueObjectSymbol = semanticModel.GetDeclaredSymbol(node, context.CancellationToken) as INamedTypeSymbol;
+
+        if (!VoFilter.IsTarget(valueObjectSymbol))
+        {
+            return;
+        }
+
+        var suppression = Suppression.Create(_suppressIComparableWarning, diagnostic);
+        context.ReportSuppression(suppression);
+    }
+}
\ No newline at end of file
diff --git a/tests/AnalyzerTests/CA1036SuppressionTests.cs b/tests/AnalyzerTests/CA1036SuppressionTests.cs
new file mode 100644
index 0000000000..75e982ac26
--- /dev/null
+++ b/tests/AnalyzerTests/CA1036SuppressionTests.cs
@@ -0,0 +1,64 @@
+using System.Collections.Immutable;
+using System.Threading.Tasks;
+using FluentAssertions;
+using Microsoft.CodeAnalysis;
+using Shared;
+using Vogen;
+using Vogen.Suppressors;
+
+namespace AnalyzerTests;
+
+public class CA1036SuppressionTests
+{
+    [Fact]
+    public async Task Suppressed_for_value_object()
+    {
+        var source = $$"""
+using System;
+using Vogen;
+
+namespace Whatever;
+
+[ValueObject<int>]
+public partial class CustomerId : IComparable<CustomerId>
+{
+}
+""";
+
+        (ImmutableArray<Diagnostic> Diagnostics, SyntaxTree[] GeneratedSource) r = 
+            await CreateBuilder(source).GetGeneratedOutput<ValueObjectGenerator>(ignoreInitialCompilationErrors: false);
+        
+            r.Diagnostics.Should().HaveCount(0);
+    }
+
+    [Fact]
+    public async Task Does_not_suppress_other_types()
+    {
+        var source = $$"""
+using System;
+using Vogen;
+
+namespace Whatever;
+
+public partial class CustomerId : IComparable<CustomerId>
+{
+	public int CompareTo(CustomerId other)
+	{
+		return 1;
+	}
+}
+""";
+
+        (ImmutableArray<Diagnostic> Diagnostics, SyntaxTree[] GeneratedSource) r = 
+            await CreateBuilder(source).GetGeneratedOutput<ValueObjectGenerator>(ignoreInitialCompilationErrors: false);
+        
+            r.Diagnostics.Should().HaveCount(1);
+            r.Diagnostics[0].Id.Should().Be("CA1036");
+    }
+
+    private static ProjectBuilder CreateBuilder(string source) => new ProjectBuilder()
+        .WithUserSource(source)
+        .WithAnalyzer<CA1036ComparisonSuppressor>()
+        .WithTargetFramework(TargetFramework.Net8_0)
+        .WithMicrosoftCodeAnalysisNetAnalyzers("CA1036");
+}
\ No newline at end of file