From c0e0430be68e77326d16a210de8c14dfec6bb064 Mon Sep 17 00:00:00 2001
From: Domn Werner <domn.werner@gmail.com>
Date: Wed, 6 Jul 2022 20:47:33 -0700
Subject: [PATCH] Support multiple records with same name (#38)

* Remove unused union record generator code.
* Support multiple unions with the same name.
* Clarify union attribute constant names.
* Union attribute source naming improvements.
---
 .../UnionAttributeGenerator.cs                |  4 ++--
 .../UnionAttributeSource.cs                   |  8 ++++----
 .../UnionRecordGenerator.cs                   | 20 ++++++++-----------
 src/IsExternalInit.cs                         |  2 +-
 4 files changed, 15 insertions(+), 19 deletions(-)

diff --git a/src/GenerateUnionAttribute/UnionAttributeGenerator.cs b/src/GenerateUnionAttribute/UnionAttributeGenerator.cs
index 3a1e6bf..bc1f5da 100644
--- a/src/GenerateUnionAttribute/UnionAttributeGenerator.cs
+++ b/src/GenerateUnionAttribute/UnionAttributeGenerator.cs
@@ -12,8 +12,8 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
         context.RegisterPostInitializationOutput(
             ctx =>
                 ctx.AddSource(
-                    "UnionAttribute.g.cs",
-                    SourceText.From(UnionAttributeSource.Attribute, Encoding.UTF8)
+                    $"{UnionAttributeSource.Name}.g.cs",
+                    SourceText.From(UnionAttributeSource.SourceCode, Encoding.UTF8)
                 )
         );
     }
diff --git a/src/GenerateUnionAttribute/UnionAttributeSource.cs b/src/GenerateUnionAttribute/UnionAttributeSource.cs
index 43d0e7f..bc725cb 100644
--- a/src/GenerateUnionAttribute/UnionAttributeSource.cs
+++ b/src/GenerateUnionAttribute/UnionAttributeSource.cs
@@ -2,11 +2,11 @@
 
 internal class UnionAttributeSource
 {
-    public const string AttributeNamespace = "Dunet";
-    public const string AttributeName = "UnionAttribute";
-    public const string FullAttributeName = $"{AttributeNamespace}.{AttributeName}";
+    public const string Namespace = "Dunet";
+    public const string Name = "UnionAttribute";
+    public const string FullyQualifiedName = $"{Namespace}.{Name}";
 
-    public const string Attribute =
+    public const string SourceCode =
         @"using System;
 
 namespace Dunet;
diff --git a/src/GenerateUnionRecord/UnionRecordGenerator.cs b/src/GenerateUnionRecord/UnionRecordGenerator.cs
index 7be56d7..20bb113 100644
--- a/src/GenerateUnionRecord/UnionRecordGenerator.cs
+++ b/src/GenerateUnionRecord/UnionRecordGenerator.cs
@@ -13,14 +13,14 @@ public class UnionRecordGenerator : IIncrementalGenerator
 {
     public void Initialize(IncrementalGeneratorInitializationContext context)
     {
-        var recordDeclarations = context.SyntaxProvider
+        var targets = context.SyntaxProvider
             .CreateSyntaxProvider(
                 predicate: static (node, _) => node.IsDecoratedRecord(),
                 transform: static (ctx, _) => GetGenerationTarget(ctx)
             )
             .Where(static m => m is not null);
 
-        var compilation = context.CompilationProvider.Combine(recordDeclarations.Collect());
+        var compilation = context.CompilationProvider.Combine(targets.Collect());
 
         context.RegisterSourceOutput(
             compilation,
@@ -47,7 +47,7 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
 
                 var fullAttributeName = attributeSymbol.ToDisplayString();
 
-                if (fullAttributeName is UnionAttributeSource.FullAttributeName)
+                if (fullAttributeName is UnionAttributeSource.FullyQualifiedName)
                 {
                     return recordDeclaration;
                 }
@@ -68,23 +68,19 @@ SourceProductionContext context
             return;
         }
 
-        var distinctRecords = recordDeclarations.Distinct();
-
         var unionRecords = GetCodeToGenerate(
             compilation,
-            distinctRecords,
+            recordDeclarations,
             context.CancellationToken
         );
 
-        if (unionRecords.Count <= 0)
-        {
-            return;
-        }
-
         foreach (var unionRecord in unionRecords)
         {
             var result = UnionRecordSource.GenerateRecord(unionRecord);
-            context.AddSource($"{unionRecord.Name}.g.cs", SourceText.From(result, Encoding.UTF8));
+            context.AddSource(
+                $"{unionRecord.Namespace}.{unionRecord.Name}.g.cs",
+                SourceText.From(result, Encoding.UTF8)
+            );
         }
     }
 
diff --git a/src/IsExternalInit.cs b/src/IsExternalInit.cs
index 8acae1a..4c5d528 100644
--- a/src/IsExternalInit.cs
+++ b/src/IsExternalInit.cs
@@ -11,4 +11,4 @@ namespace System.Runtime.CompilerServices;
 /// Predefined type 'System.Runtime.CompilerServices.IsExternalInit' is not defined or imported
 /// </remarks>
 [EditorBrowsable(EditorBrowsableState.Never)]
-sealed class IsExternalInit { }
+internal sealed class IsExternalInit { }