Add constraints to CaptureParameters method

src/Compiler/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentCodeGenerationTestBase.cs

@@ -9279,6 +9279,31 @@ private class String
         CompileToAssembly(generated);
     }
 
+    [IntegrationTestFact, WorkItem("https://github.com/dotnet/razor/issues/11505")]
+    public void CaptureParametersConstraint()
+    {
+        AdditionalSyntaxTrees.Add(Parse("""
+            using Microsoft.AspNetCore.Components;
+
+            namespace Test;
+
+            public interface IMyInterface;
+
+            public class MyClass<T> where T : IMyInterface;
+
+            [CascadingTypeParameter(nameof(T))]
+            public class MyComponent<T> : ComponentBase where T : IMyInterface
+            {
+                [Parameter] public MyClass<T> Param { get; set; }
+            }
+            """));
+        var generated = CompileToCSharp("""
+            <MyComponent Param="new MyClass<IMyInterface>()" />
+            """);
+        AssertCSharpDocumentMatchesBaseline(generated.CodeDocument);
+        CompileToAssembly(generated);
+    }
+
     #endregion
 
     #region Key

src/Compiler/Microsoft.AspNetCore.Razor.Language/test/TestFiles/IntegrationTests/ComponentDesignTimeCodeGenerationTest/CaptureParametersConstraint/TestComponent.codegen.cs

@@ -0,0 +1,82 @@
+// <auto-generated/>
+#pragma warning disable 1591
+namespace Test
+{
+    #line default
+    using global::System;
+    using global::System.Collections.Generic;
+    using global::System.Linq;
+    using global::System.Threading.Tasks;
+    using global::Microsoft.AspNetCore.Components;
+    #line default
+    #line hidden
+    #nullable restore
+    public partial class TestComponent : global::Microsoft.AspNetCore.Components.ComponentBase
+    #nullable disable
+    {
+        #pragma warning disable 219
+        private void __RazorDirectiveTokenHelpers__() {
+        }
+        #pragma warning restore 219
+        #pragma warning disable 0414
+        private static object __o = null;
+        #pragma warning restore 0414
+        #pragma warning disable 1998
+        protected override void BuildRenderTree(global::Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder __builder)
+        {
+            {
+                global::__Blazor.Test.TestComponent.TypeInference.CreateMyComponent_0_CaptureParameters(
+#nullable restore
+#line 1 "x:\dir\subdir\Test\TestComponent.cshtml"
+                    new MyClass<IMyInterface>()
+
+#line default
+#line hidden
+#nullable disable
+                , out var __typeInferenceArg_0___arg0);
+                var __typeInference_CreateMyComponent_0 = global::__Blazor.Test.TestComponent.TypeInference.CreateMyComponent_0(__builder, -1, -1, __typeInferenceArg_0___arg0);
+                #pragma warning disable BL0005
+                __typeInference_CreateMyComponent_0.
+#nullable restore
+#line 1 "x:\dir\subdir\Test\TestComponent.cshtml"
+             Param
+
+#line default
+#line hidden
+#nullable disable
+                 = default;
+                #pragma warning restore BL0005
+            }
+#nullable restore
+#line 1 "x:\dir\subdir\Test\TestComponent.cshtml"
+__o = typeof(global::Test.MyComponent<>);
+
+#line default
+#line hidden
+#nullable disable
+        }
+        #pragma warning restore 1998
+    }
+}
+namespace __Blazor.Test.TestComponent
+{
+    #line hidden
+    internal static class TypeInference
+    {
+        public static global::Test.MyComponent<T> CreateMyComponent_0<T>(global::Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder __builder, int seq, int __seq0, global::Test.MyClass<T> __arg0)
+            where T : global::Test.IMyInterface
+        {
+        __builder.OpenComponent<global::Test.MyComponent<T>>(seq);
+        __builder.AddAttribute(__seq0, "Param", (object)__arg0);
+        __builder.CloseComponent();
+        return default;
+        }
+
+        public static void CreateMyComponent_0_CaptureParameters<T>(global::Test.MyClass<T> __arg0, out global::Test.MyClass<T> __arg0_out)
+            where T : global::Test.IMyInterface
+        {
+            __arg0_out = __arg0;
+        }
+    }
+}
+#pragma warning restore 1591

src/Compiler/Microsoft.AspNetCore.Razor.Language/test/TestFiles/IntegrationTests/ComponentDesignTimeCodeGenerationTest/CaptureParametersConstraint/TestComponent.mappings.txt

@@ -0,0 +1,10 @@
+Source Location: (20:0,20 [27] x:\dir\subdir\Test\TestComponent.cshtml)
+|new MyClass<IMyInterface>()|
+Generated Location: (1126:30,20 [27] )
+|new MyClass<IMyInterface>()|
+
+Source Location: (13:0,13 [5] x:\dir\subdir\Test\TestComponent.cshtml)
+|Param|
+Generated Location: (1625:41,13 [5] )
+|Param|
+

src/Compiler/Microsoft.AspNetCore.Razor.Language/test/TestFiles/IntegrationTests/ComponentRuntimeCodeGenerationTest/CaptureParametersConstraint/TestComponent.codegen.cs

@@ -0,0 +1,65 @@
+// <auto-generated/>
+#pragma warning disable 1591
+namespace Test
+{
+    #line default
+    using global::System;
+    using global::System.Collections.Generic;
+    using global::System.Linq;
+    using global::System.Threading.Tasks;
+    using global::Microsoft.AspNetCore.Components;
+    #line default
+    #line hidden
+    #nullable restore
+    public partial class TestComponent : global::Microsoft.AspNetCore.Components.ComponentBase
+    #nullable disable
+    {
+        #pragma warning disable 1998
+        protected override void BuildRenderTree(global::Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder __builder)
+        {
+            {
+                global::__Blazor.Test.TestComponent.TypeInference.CreateMyComponent_0_CaptureParameters(
+#nullable restore
+#line (1,21)-(1,48) "x:\dir\subdir\Test\TestComponent.cshtml"
+new MyClass<IMyInterface>()
+
+#line default
+#line hidden
+#nullable disable
+                , out var __typeInferenceArg_0___arg0);
+                global::__Blazor.Test.TestComponent.TypeInference.CreateMyComponent_0(__builder, 0, 1, __typeInferenceArg_0___arg0);
+                __typeInferenceArg_0___arg0 = default;
+            }
+        }
+        #pragma warning restore 1998
+    }
+}
+namespace __Blazor.Test.TestComponent
+{
+    #line hidden
+    internal static class TypeInference
+    {
+        public static void CreateMyComponent_0<T>(global::Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder __builder, int seq, int __seq0, global::Test.MyClass<T> __arg0)
+            where T : global::Test.IMyInterface
+        {
+        __builder.OpenComponent<global::Test.MyComponent<T>>(seq);
+        __builder.AddComponentParameter(__seq0, nameof(global::Test.MyComponent<T>.
+#nullable restore
+#line (1,14)-(1,19) "x:\dir\subdir\Test\TestComponent.cshtml"
+Param
+
+#line default
+#line hidden
+#nullable disable
+        ), __arg0);
+        __builder.CloseComponent();
+        }
+
+        public static void CreateMyComponent_0_CaptureParameters<T>(global::Test.MyClass<T> __arg0, out global::Test.MyClass<T> __arg0_out)
+            where T : global::Test.IMyInterface
+        {
+            __arg0_out = __arg0;
+        }
+    }
+}
+#pragma warning restore 1591

src/Compiler/Microsoft.AspNetCore.Razor.Language/test/TestFiles/IntegrationTests/ComponentRuntimeCodeGenerationTest/CaptureParametersConstraint/TestComponent.mappings.txt

@@ -0,0 +1,10 @@
+Source Location: (20:0,20 [27] x:\dir\subdir\Test\TestComponent.cshtml)
+|new MyClass<IMyInterface>()|
+Generated Location: (857:23,0 [27] )
+|new MyClass<IMyInterface>()|
+
+Source Location: (13:0,13 [5] x:\dir\subdir\Test\TestComponent.cshtml)
+|Param|
+Generated Location: (1843:48,0 [5] )
+|Param|
+

src/Compiler/Microsoft.CodeAnalysis.Razor.Compiler/src/Language/Components/ComponentNodeWriter.cs

@@ -153,19 +153,7 @@ protected void WriteComponentTypeInferenceMethod(CodeRenderingContext context, C
 
         writer.Write(")");
 
-        // Writes out a list of generic type constraints with indentation
-        // public void Foo<T, U>(T t, U u)
-        //      where T: new()
-        //      where U: Foo, notnull
-        foreach (var constraint in node.GenericTypeConstraints)
-        {
-            writer.WriteLine();
-            writer.Indent(writer.CurrentIndent + writer.TabSize);
-            writer.Write(constraint);
-
-        }
-
-        writer.WriteLine();
+        writeConstraints(writer, node);
 
         writer.WriteLine("{");
 
@@ -319,7 +307,10 @@ protected void WriteComponentTypeInferenceMethod(CodeRenderingContext context, C
                 writer.Write("_out");
             }
 
-            writer.WriteLine(")");
+            writer.Write(")");
+
+            writeConstraints(writer, node);
+
             writer.WriteLine("{");
             foreach (var parameter in parameters.Where(p => p.UsedForTypeInference))
             {
@@ -331,6 +322,22 @@ protected void WriteComponentTypeInferenceMethod(CodeRenderingContext context, C
             }
             writer.WriteLine("}");
         }
+
+        static void writeConstraints(CodeWriter writer, ComponentTypeInferenceMethodIntermediateNode node)
+        {
+            // Writes out a list of generic type constraints with indentation
+            // public void Foo<T, U>(T t, U u)
+            //      where T: new()
+            //      where U: Foo, notnull
+            foreach (var constraint in node.GenericTypeConstraints)
+            {
+                writer.WriteLine();
+                writer.Indent(writer.CurrentIndent + writer.TabSize);
+                writer.Write(constraint);
+            }
+
+            writer.WriteLine();
+        }
     }
 
     protected static void WriteComponentAttributeName(CodeRenderingContext context, ComponentAttributeIntermediateNode attribute, bool allowNameof = true)