Suppress CS1591 warnings for PublicTopLevelProgram.Generated.g.cs (#60727)

* Added pragma to suppress CS1591 in generated code

* Fixed program declaration in explicit namespace

* Accounted for comments, reverting additional logic

Author: benhopkinstech

src/Framework/AspNetCoreAnalyzers/src/SourceGenerators/PublicTopLevelProgramGenerator.cs

@@ -12,7 +12,9 @@ public class PublicProgramSourceGenerator : IIncrementalGenerator
 {
     private const string PublicPartialProgramClassSource = """
 // <auto-generated />
+#pragma warning disable CS1591
 public partial class Program { }
+#pragma warning restore CS1591
 """;
 
     public void Initialize(IncrementalGeneratorInitializationContext context)
@@ -21,17 +23,17 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
             // Get the entry point associated with the compilation, this maps to the Main method definition
             // Get the containing symbol of the entry point, this maps to the Program class
             compilation.GetEntryPoint(cancellationToken)?.ContainingSymbol is INamedTypeSymbol
-                {
-                    // If the discovered `Program` type is not a class then its not
-                    // generated and has been defined in source, so we can skip it
-                    // If the program class is already public, we don't need to generate anything.
-                    DeclaredAccessibility: not Accessibility.Public,
-                    TypeKind: TypeKind.Class,
-                    // If there are multiple partial declarations, then do nothing since we don't want
-                    // to trample on visibility explicitly set by the user
-                    DeclaringSyntaxReferences: { Length: 1 } declaringSyntaxReferences
-                } &&
-            // If the `Program` class is already declared in user code, we don't need to generate anything.
+            {
+                // If the program class is already public, we don't need to generate anything
+                DeclaredAccessibility: not Accessibility.Public,
+                // If the discovered `Program` type is not a class then its not
+                // generated and has been defined in source, so we can skip it
+                TypeKind: TypeKind.Class,
+                // If there are multiple partial declarations, then do nothing since we don't want
+                // to trample on visibility explicitly set by the user
+                DeclaringSyntaxReferences: { Length: 1 } declaringSyntaxReferences
+            } &&
+            // If the `Program` class is already declared in user code, we don't need to generate anything
             declaringSyntaxReferences.Single().GetSyntax(cancellationToken) is not ClassDeclarationSyntax
         );
 

src/Framework/AspNetCoreAnalyzers/test/SourceGenerators/PublicTopLevelProgramGeneratorTests.cs

@@ -7,6 +7,13 @@ namespace Microsoft.AspNetCore.SourceGenerators.Tests;
 
 public class PublicTopLevelProgramGeneratorTests
 {
+    private const string ExpectedGeneratedSource = """
+// <auto-generated />
+#pragma warning disable CS1591
+public partial class Program { }
+#pragma warning restore CS1591
+""";
+
     [Fact]
     public async Task GeneratesSource_ProgramWithTopLevelStatements()
     {
@@ -20,12 +27,33 @@ public async Task GeneratesSource_ProgramWithTopLevelStatements()
 app.Run();
 """;
 
-        var expected = """
-// <auto-generated />
-public partial class Program { }
+        await VerifyCS.VerifyAsync(source, "PublicTopLevelProgram.Generated.g.cs", ExpectedGeneratedSource);
+    }
+
+    // The compiler synthesizes a Program class in the global namespace due to top-level statements
+    // The Foo.Program class is completely unrelated to the entry point and is just as any regular type
+    // Hence, we will expect to see the source generated in these scenarios
+    [Theory]
+    [InlineData("public partial class Program { }")]
+    [InlineData("internal partial class Program { }")]
+    public async Task GeneratesSource_IfProgramDefinedInANamespace (string declaration)
+    {
+        var source = $$"""
+using Microsoft.AspNetCore.Builder;
+
+var app = WebApplication.Create();
+
+app.MapGet("/", () => "Hello, World!");
+
+app.Run();
+
+namespace Foo
+{
+    {{declaration}}
+}
 """;
 
-        await VerifyCS.VerifyAsync(source, "PublicTopLevelProgram.Generated.g.cs", expected);
+        await VerifyCS.VerifyAsync(source, "PublicTopLevelProgram.Generated.g.cs", ExpectedGeneratedSource);
     }
 
     [Fact]
@@ -86,6 +114,31 @@ public static void Main()
         await VerifyCS.VerifyAsync(source);
     }
 
+    [Fact]
+    public async Task DoesNotGeneratorSource_ExplicitPublicProgramClassInNamespace()
+    {
+        var source = """
+using Microsoft.AspNetCore.Builder;
+
+namespace Foo
+{
+    public class Program
+    {
+        public static void Main()
+        {
+            var app = WebApplication.Create();
+
+            app.MapGet("/", () => "Hello, World!");
+
+            app.Run();
+        }
+    }
+}
+""";
+
+        await VerifyCS.VerifyAsync(source);
+    }
+
     [Fact]
     public async Task DoesNotGeneratorSource_ExplicitInternalProgramClass()
     {
@@ -108,6 +161,31 @@ public static void Main()
         await VerifyCS.VerifyAsync(source);
     }
 
+    [Fact]
+    public async Task DoesNotGeneratorSource_ExplicitInternalProgramClassInNamespace()
+    {
+        var source = """
+using Microsoft.AspNetCore.Builder;
+
+namespace Foo
+{
+    internal class Program
+    {
+        public static void Main()
+        {
+            var app = WebApplication.Create();
+
+            app.MapGet("/", () => "Hello, World!");
+
+            app.Run();
+        }
+    }
+}
+""";
+
+        await VerifyCS.VerifyAsync(source);
+    }
+
     [Theory]
     [InlineData("interface")]
     [InlineData("struct")]
@@ -127,6 +205,33 @@ public static void Main(string[] args)
         app.Run();
     }
 }
+""";
+
+        await VerifyCS.VerifyAsync(source);
+    }
+
+    [Theory]
+    [InlineData("interface")]
+    [InlineData("struct")]
+    public async Task DoesNotGeneratorSource_ExplicitInternalProgramTypeInNamespace(string type)
+    {
+        var source = $$"""
+using Microsoft.AspNetCore.Builder;
+
+namespace Foo
+{
+    internal {{type}} Program
+    {
+        public static void Main(string[] args)
+        {
+            var app = WebApplication.Create();
+
+            app.MapGet("/", () => "Hello, World!");
+
+            app.Run();
+        }
+    }
+}
 """;
 
         await VerifyCS.VerifyAsync(source);