Update requiredness checks for BindAsync params

Author: captainsafia

src/Http/Http.Extensions/gen/StaticRouteHandlerModel/Emitters/EmitterExtensions.cs

@@ -42,7 +42,7 @@ public static bool IsSerializableJsonResponse(this EndpointResponse endpointResp
         // the underlying value for a nullable value type instead of using the non-nullable reference type modifier.
         EndpointParameterSource.BindAsync => endpointParameter.IsOptional ?
             endpointParameter.EmitHandlerArgument() :
-            endpointParameter.Type.IsValueType && endpointParameter.GetBindAsyncReturnType()?.OriginalDefinition.SpecialType == SpecialType.System_Nullable_T
+            endpointParameter.Type.IsValueType && endpointParameter.GetBindAsyncReturnType().IsNullableOfT()
                 ? $"{endpointParameter.EmitHandlerArgument()}.HasValue ? {endpointParameter.EmitHandlerArgument()}.Value : default"
                 : $"{endpointParameter.EmitHandlerArgument()}",
         EndpointParameterSource.Unknown => throw new NotImplementedException("Unreachable!"),

src/Http/Http.Extensions/gen/StaticRouteHandlerModel/Emitters/EndpointParameterEmitter.cs

@@ -294,7 +294,9 @@ internal static void EmitBindAsyncPreparation(this EndpointParameter endpointPar
 
         if (!endpointParameter.IsOptional)
         {
-            codeWriter.WriteLine($"if ({endpointParameter.EmitHandlerArgument()} == null)");
+            codeWriter.WriteLine(endpointParameter.Type.IsValueType && endpointParameter.GetBindAsyncReturnType().IsNullableOfT()
+                ? $"if (!{endpointParameter.EmitHandlerArgument()}.HasValue)"
+                : $"if ({endpointParameter.EmitHandlerArgument()} == null)");
             codeWriter.StartBlock();
             codeWriter.WriteLine($@"logOrThrowExceptionHelper.RequiredParameterNotProvided({SymbolDisplay.FormatLiteral(endpointParameter.Type.ToDisplayString(SymbolDisplayFormat.CSharpShortErrorMessageFormat), true)}, {SymbolDisplay.FormatLiteral(endpointParameter.SymbolName, true)}, {SymbolDisplay.FormatLiteral(endpointParameter.ToMessageString(), true)});");
             codeWriter.WriteLine("wasParamCheckFailure = true;");

src/Http/Http.Extensions/gen/StaticRouteHandlerModel/Model/EndpointParameterExtensions.cs

@@ -41,4 +41,7 @@ public static ITypeSymbol UnwrapParameterType(this EndpointParameter parameter)
 
     public static ITypeSymbol? GetBindAsyncReturnType(this EndpointParameter parameter)
         => ((INamedTypeSymbol?)parameter.BindableMethodSymbol?.ReturnType)?.TypeArguments[0];
+
+    public static bool IsNullableOfT(this ITypeSymbol? typeSymbol)
+        => typeSymbol?.OriginalDefinition.SpecialType == SpecialType.System_Nullable_T;
 }

src/Http/Http.Extensions/test/RequestDelegateGenerator/Baselines/MapAction_BindAsync_NullableReturn.generated.txt

@@ -209,7 +209,7 @@ namespace Microsoft.AspNetCore.Http.Generated
                 {
                     var wasParamCheckFailure = false;
                     var param_local = await global::Microsoft.AspNetCore.Http.Generators.Tests.BindableStructWithNullReturn.BindAsync(httpContext, parameters[0]);
-                    if (param_local == null)
+                    if (!param_local.HasValue)
                     {
                         logOrThrowExceptionHelper.RequiredParameterNotProvided("BindableStructWithNullReturn", "param", "BindableStructWithNullReturn.BindAsync(HttpContext, ParameterInfo)");
                         wasParamCheckFailure = true;
@@ -237,7 +237,7 @@ namespace Microsoft.AspNetCore.Http.Generated
                 {
                     var wasParamCheckFailure = false;
                     var param_local = await global::Microsoft.AspNetCore.Http.Generators.Tests.BindableStructWithNullReturn.BindAsync(httpContext, parameters[0]);
-                    if (param_local == null)
+                    if (!param_local.HasValue)
                     {
                         logOrThrowExceptionHelper.RequiredParameterNotProvided("BindableStructWithNullReturn", "param", "BindableStructWithNullReturn.BindAsync(HttpContext, ParameterInfo)");
                         wasParamCheckFailure = true;

src/Http/Http.Extensions/test/RequestDelegateGenerator/Baselines/MapAction_BindAsync_Snapshot.generated.txt

@@ -504,7 +504,7 @@ namespace Microsoft.AspNetCore.Http.Generated
                     var wasParamCheckFailure = false;
                     var httpContext_local = httpContext;
                     var myBindAsyncParam_local = await global::Microsoft.AspNetCore.Http.Generators.Tests.MyNullableBindAsyncStruct.BindAsync(httpContext, parameters[1]);
-                    if (myBindAsyncParam_local == null)
+                    if (!myBindAsyncParam_local.HasValue)
                     {
                         logOrThrowExceptionHelper.RequiredParameterNotProvided("MyNullableBindAsyncStruct", "myBindAsyncParam", "MyNullableBindAsyncStruct.BindAsync(HttpContext, ParameterInfo)");
                         wasParamCheckFailure = true;
@@ -533,7 +533,7 @@ namespace Microsoft.AspNetCore.Http.Generated
                     var wasParamCheckFailure = false;
                     var httpContext_local = httpContext;
                     var myBindAsyncParam_local = await global::Microsoft.AspNetCore.Http.Generators.Tests.MyNullableBindAsyncStruct.BindAsync(httpContext, parameters[1]);
-                    if (myBindAsyncParam_local == null)
+                    if (!myBindAsyncParam_local.HasValue)
                     {
                         logOrThrowExceptionHelper.RequiredParameterNotProvided("MyNullableBindAsyncStruct", "myBindAsyncParam", "MyNullableBindAsyncStruct.BindAsync(HttpContext, ParameterInfo)");
                         wasParamCheckFailure = true;

src/Http/Http.Extensions/test/RequestDelegateGenerator/CompileTimeCreationTests.cs

@@ -6,6 +6,7 @@
 using Microsoft.AspNetCore.Http.RequestDelegateGenerator;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.Text;
+using Microsoft.Extensions.Logging;
 
 namespace Microsoft.AspNetCore.Http.Generators.Tests;
 
@@ -330,6 +331,7 @@ public async Task MapAction_BindAsync_NullableReturn()
             Assert.Equal(400, httpContext.Response.StatusCode);
         }
 
+        Assert.All(TestSink.Writes, context => Assert.Equal("RequiredParameterNotProvided", context.EventId.Name));
         await VerifyAgainstBaselineUsingFile(compilation);
     }
 }

src/Http/Http.Extensions/test/RequestDelegateGenerator/SharedTypes.cs

@@ -193,8 +193,8 @@ public static bool TryParse(string? input, IFormatProvider? provider, out Parsab
         }
         else
         {
-        result = null!;
-        return false;
+            result = null!;
+            return false;
         }
     }
 }