fix(SourceGenerator): resolve hint name collision and improve DX for new registrations (#5)

* fix(SourceGenerator): resolve hint name collision and improve DX for new registrations

  - Include namespace in UniqueId to prevent collision when same-named
    plugins exist in different namespaces
  - Remove HandlerMethodValidator that blocked generation when handler
    method was missing - types are now always generated so developers
    can reference PreImage/PostImage when creating new handler methods
  - Remove unused HasValidationError property from PluginStepMetadata
  - Add GeneratedSourceInfo to test helper for hint name verification

  Fixes chicken-and-egg problem where developers couldn't create handler
  methods with correct signatures because the generated types didn't exist.

* Fix: Checked non-existant property

Author: mkholt

XrmPluginCore.SourceGenerator.Tests/DiagnosticTests/DiagnosticReportingTests.cs

@@ -835,6 +835,235 @@ public void DoSomething() { }
 		xpc3003Diagnostics.Should().BeEmpty("XPC3003 should NOT be reported when using method reference syntax");
 	}
 
+	[Fact]
+	public void Should_Generate_Types_Even_When_Handler_Method_Not_Found()
+	{
+		// Arrange - method reference points to NonExistentMethod but types should still be generated
+		// This enables a better DX where developers can create the method with correct signature
+		// using the generated PreImage/PostImage types
+		const string pluginSource = """
+
+			using XrmPluginCore;
+			using XrmPluginCore.Enums;
+			using Microsoft.Extensions.DependencyInjection;
+			using TestNamespace;
+
+			namespace TestNamespace
+			{
+			    public class TestPlugin : Plugin
+			    {
+			        public TestPlugin()
+			        {
+			            RegisterStep<Account, ITestService>(EventOperation.Update, ExecutionStage.PostOperation,
+			                service => service.NonExistentMethod)
+			                .WithPreImage(x => x.Name);
+			        }
+
+			        protected override IServiceCollection OnBeforeBuildServiceProvider(IServiceCollection services)
+			        {
+			            return services.AddScoped<ITestService, TestService>();
+			        }
+			    }
+
+			    public interface ITestService
+			    {
+			        void Process();  // Different method, NonExistentMethod doesn't exist
+			    }
+
+			    public class TestService : ITestService
+			    {
+			        public void Process() { }
+			    }
+			}
+			""";
+
+		var source = TestFixtures.GetCompleteSource(pluginSource);
+
+		// Act
+		var result = GeneratorTestHelper.RunGenerator(
+			CompilationHelper.CreateCompilation(source));
+
+		// Assert - Types should be generated even though handler method doesn't exist
+		result.GeneratedTrees.Should().NotBeEmpty(
+			"PreImage/PostImage types should be generated even when handler method doesn't exist");
+
+		// Verify PreImage class is generated
+		var generatedSource = result.GeneratedTrees.First().ToString();
+		generatedSource.Should().Contain("public sealed class PreImage",
+			"PreImage class should be generated to allow developers to create the handler method with correct signature");
+	}
+
+	[Fact]
+	public void Should_Generate_Types_Even_When_Handler_Method_Wrong_Signature()
+	{
+		// Arrange - method reference points to MethodWithoutImage but types should still be generated
+		// This enables a better DX where developers can create the method with correct signature
+		// using the generated PreImage/PostImage types
+		const string pluginSource = """
+
+			using XrmPluginCore;
+			using XrmPluginCore.Enums;
+			using Microsoft.Extensions.DependencyInjection;
+			using TestNamespace;
+
+			namespace TestNamespace
+			{
+			    public class TestPlugin : Plugin
+			    {
+			        public TestPlugin()
+			        {
+			            RegisterStep<Account, ITestService>(EventOperation.Update, ExecutionStage.PostOperation,
+			                service => service.MethodWithoutImage)
+			                .WithPreImage(x => x.Name);
+			        }
+
+			        protected override IServiceCollection OnBeforeBuildServiceProvider(IServiceCollection services)
+			        {
+			            return services.AddScoped<ITestService, TestService>();
+			        }
+			    }
+
+			    public interface ITestService
+			    {
+			        void Process();  // Different method
+					void MethodWithoutImage(); // Method exists but wrong signature (missing PreImage parameter)
+			    }
+
+			    public class TestService : ITestService
+			    {
+			        public void Process() { }
+					public void MethodWithoutImage() { }
+			    }
+			}
+			""";
+
+		var source = TestFixtures.GetCompleteSource(pluginSource);
+
+		// Act
+		var result = GeneratorTestHelper.RunGenerator(
+			CompilationHelper.CreateCompilation(source));
+
+		// Assert - Types should be generated even though handler method doesn't exist
+		result.GeneratedTrees.Should().NotBeEmpty(
+			"PreImage/PostImage types should be generated even when handler method doesn't exist");
+
+		// Verify PreImage class is generated
+		var generatedSource = result.GeneratedTrees.First().ToString();
+		generatedSource.Should().Contain("public sealed class PreImage",
+			"PreImage class should be generated to allow developers to create the handler method with correct signature");
+
+		generatedSource.Should().Contain("namespace TestNamespace.PluginRegistrations.TestPlugin.AccountUpdatePostOperation",
+			"Generated types should be in the correct namespace");
+	}
+
+	[Fact]
+	public void Should_Generate_Unique_Files_For_Same_Named_Plugins_In_Different_Namespaces()
+	{
+		// Arrange - Two plugins with the same class name but in different namespaces
+		// Both register the same entity/operation/stage combination
+		// Previously this would cause a hint name collision
+		// Note: We don't use GetCompleteSource here because it strips namespaces
+		const string source = """
+			using System;
+			using Microsoft.Xrm.Sdk;
+			using XrmPluginCore;
+			using XrmPluginCore.Enums;
+			using Microsoft.Extensions.DependencyInjection;
+			using XrmPluginCore.Tests.Context.BusinessDomain;
+
+			namespace Namespace1
+			{
+			    public class AccountPlugin : Plugin
+			    {
+			        public AccountPlugin()
+			        {
+			            RegisterStep<Account, ITestService>(EventOperation.Update, ExecutionStage.PostOperation,
+			                service => service.HandleUpdate)
+			                .WithPreImage(x => x.Name);
+			        }
+
+			        protected override IServiceCollection OnBeforeBuildServiceProvider(IServiceCollection services)
+			        {
+			            return services.AddScoped<ITestService, TestService>();
+			        }
+			    }
+
+			    public interface ITestService
+			    {
+			        void HandleUpdate();
+			    }
+
+			    public class TestService : ITestService
+			    {
+			        public void HandleUpdate() { }
+			    }
+			}
+
+			namespace Namespace2
+			{
+			    public class AccountPlugin : Plugin
+			    {
+			        public AccountPlugin()
+			        {
+			            RegisterStep<Account, ITestService>(EventOperation.Update, ExecutionStage.PostOperation,
+			                service => service.HandleUpdate)
+			                .WithPreImage(x => x.AccountNumber);
+			        }
+
+			        protected override IServiceCollection OnBeforeBuildServiceProvider(IServiceCollection services)
+			        {
+			            return services.AddScoped<ITestService, TestService>();
+			        }
+			    }
+
+			    public interface ITestService
+			    {
+			        void HandleUpdate();
+			    }
+
+			    public class TestService : ITestService
+			    {
+			        public void HandleUpdate() { }
+			    }
+			}
+			""";
+
+		// Act
+		var result = GeneratorTestHelper.RunGenerator(
+			CompilationHelper.CreateCompilation(source));
+
+		// Assert - Both plugins should generate separate files with unique hint names
+		result.GeneratedSources.Should().HaveCount(2,
+			"both plugins should generate code without hint name collision");
+
+		// Index sources by hint name for precise verification
+		var sourcesByHintName = result.GeneratedSources.ToDictionary(gs => gs.HintName, gs => gs.SourceText);
+
+		// Find the hint names for each namespace
+		var namespace1HintName = sourcesByHintName.Keys.Single(h => h.Contains("Namespace1_"));
+		var namespace2HintName = sourcesByHintName.Keys.Single(h => h.Contains("Namespace2_"));
+
+		// Verify Namespace1 source: correct namespace AND correct property (Name)
+		var namespace1Source = sourcesByHintName[namespace1HintName];
+		namespace1Source.Should().Contain("namespace Namespace1.PluginRegistrations.AccountPlugin.AccountUpdatePostOperation",
+			"Namespace1 hint name should map to Namespace1 generated namespace");
+		namespace1Source.Should().Contain("public string Name =>",
+			"Namespace1 plugin registered Name attribute");
+
+		// Verify Namespace2 source: correct namespace AND correct property (AccountNumber)
+		var namespace2Source = sourcesByHintName[namespace2HintName];
+		namespace2Source.Should().Contain("namespace Namespace2.PluginRegistrations.AccountPlugin.AccountUpdatePostOperation",
+			"Namespace2 hint name should map to Namespace2 generated namespace");
+		namespace2Source.Should().Contain("public string AccountNumber =>",
+			"Namespace2 plugin registered AccountNumber attribute");
+
+		// Verify each source only contains its own namespace (not cross-contaminated)
+		namespace1Source.Should().NotContain("namespace Namespace2",
+			"Namespace1 source should not contain Namespace2 namespace declaration");
+		namespace2Source.Should().NotContain("namespace Namespace1",
+			"Namespace2 source should not contain Namespace1 namespace declaration");
+	}
+
 	private static async Task<ImmutableArray<Diagnostic>> GetAnalyzerDiagnosticsAsync(string source, DiagnosticAnalyzer analyzer)
 	{
 		var compilation = CompilationHelper.CreateCompilation(source);

XrmPluginCore.SourceGenerator.Tests/Helpers/GeneratorTestHelper.cs

@@ -35,11 +35,17 @@ public static GeneratorRunResult RunGenerator(CSharpCompilation compilation)
 			.Where(tree => !compilation.SyntaxTrees.Contains(tree))
 			.ToArray();
 
+		// Get generated sources with hint names from the run result
+		var generatedSources = runResult.Results[0].GeneratedSources
+			.Select(gs => new GeneratedSourceInfo(gs.HintName, gs.SourceText.ToString()))
+			.ToArray();
+
 		return new GeneratorRunResult
 		{
 			OutputCompilation = (CSharpCompilation)outputCompilation,
 			Diagnostics = [.. diagnostics],
 			GeneratedTrees = generatedTrees,
+			GeneratedSources = generatedSources,
 			GeneratorDiagnostics = [.. runResult.Results[0].Diagnostics]
 		};
 	}
@@ -105,9 +111,15 @@ public class GeneratorRunResult
 	public required CSharpCompilation OutputCompilation { get; init; }
 	public required Diagnostic[] Diagnostics { get; init; }
 	public required SyntaxTree[] GeneratedTrees { get; init; }
+	public required GeneratedSourceInfo[] GeneratedSources { get; init; }
 	public required Diagnostic[] GeneratorDiagnostics { get; init; }
 }
 
+/// <summary>
+/// Information about a generated source file including its hint name.
+/// </summary>
+public record GeneratedSourceInfo(string HintName, string SourceText);
+
 /// <summary>
 /// Result from compiling generated code.
 /// </summary>

XrmPluginCore.SourceGenerator/Generators/PluginImageGenerator.cs

@@ -9,7 +9,6 @@
 using XrmPluginCore.SourceGenerator.Helpers;
 using XrmPluginCore.SourceGenerator.Models;
 using XrmPluginCore.SourceGenerator.Parsers;
-using XrmPluginCore.SourceGenerator.Validation;
 
 namespace XrmPluginCore.SourceGenerator.Generators;
 
@@ -94,11 +93,6 @@ private static IEnumerable<PluginStepMetadata> TransformToMetadata(
 			if (mergedMetadata is null)
 				continue;
 
-			// Validate handler method signature
-			HandlerMethodValidator.ValidateHandlerMethod(
-				mergedMetadata,
-				semanticModel.Compilation);
-
 			// Include if:
 			// - Has method reference (for ActionWrapper generation)
 			// - OR has images with attributes (for image wrapper generation)
@@ -185,10 +179,6 @@ private void GenerateSourceFromMetadata(
 			}
 		}
 
-		// Skip generation if validation failed (analyzer will report the error)
-		if (metadata?.HasValidationError == true)
-			return;
-
 		// Generate code if we have a handler method reference (ActionWrapper always needed)
 		if (string.IsNullOrEmpty(metadata?.HandlerMethodName))
 			return;

XrmPluginCore.SourceGenerator/Models/PluginStepMetadata.cs

@@ -42,12 +42,6 @@ internal sealed class PluginStepMetadata
 	/// </summary>
 	public List<DiagnosticInfo> Diagnostics { get; set; } = [];
 
-	/// <summary>
-	/// If true, generation should be skipped for this registration due to validation errors.
-	/// The analyzer will report the appropriate diagnostic. Not included in equality comparison.
-	/// </summary>
-	public bool HasValidationError { get; set; }
-
 	/// <summary>
 	/// Gets the namespace for generated wrapper classes.
 	/// Format: {OriginalNamespace}.PluginRegistrations.{PluginClassName}.{Entity}{Op}{Stage}
@@ -57,10 +51,11 @@ internal sealed class PluginStepMetadata
 
 	/// <summary>
 	/// Gets a unique identifier for this registration.
-	/// Includes plugin class name to differentiate multiple registrations for the same entity/operation/stage.
+	/// Includes namespace and plugin class name to differentiate multiple registrations
+	/// for the same entity/operation/stage across different namespaces.
 	/// </summary>
 	public string UniqueId =>
-		$"{PluginClassName}_{EntityTypeName}_{EventOperation}_{ExecutionStage}";
+		$"{Namespace?.Replace(".", "_")}_{PluginClassName}_{EntityTypeName}_{EventOperation}_{ExecutionStage}";
 
 	public override bool Equals(object obj)
 	{