Propagate PropertyInfo for AsParameters parameters (#57264)

* Propagate PropertyInfo for AsParameters parameters

* Apply PR suggestions

* Better with previous implementation but taking into account parameter

---------

Co-authored-by: Javier García de la Noceda Argüelles <jgarcian@riamoneytransfer.com>

Author: jgarciadelanoceda

src/Mvc/Mvc.ApiExplorer/src/EndpointMetadataApiDescriptionProvider.cs

@@ -188,7 +188,7 @@ private ApiDescription CreateApiDescription(RouteEndpoint routeEndpoint, string
         return new ApiParameterDescription
         {
             Name = name,
-            ModelMetadata = CreateModelMetadata(paramType),
+            ModelMetadata = CreateModelMetadata(parameter, paramType),
             Source = source,
             DefaultValue = parameter.ParameterInfo.DefaultValue,
             Type = parameter.ParameterInfo.ParameterType,
@@ -436,6 +436,19 @@ private static ApiResponseType CreateDefaultApiResponseType(Type responseType)
     private static EndpointModelMetadata CreateModelMetadata(Type type) =>
         new(ModelMetadataIdentity.ForType(type));
 
+    private static EndpointModelMetadata CreateModelMetadata(IParameterBindingMetadata parameter, Type type)
+    {
+        if (parameter.ParameterInfo is { } parameterInfo)
+        {
+            if (parameterInfo.Member is PropertyInfo propertyInfo && propertyInfo.DeclaringType is not null)
+            {
+                return new(ModelMetadataIdentity.ForProperty(propertyInfo, type, propertyInfo.DeclaringType));
+            }
+            return new(ModelMetadataIdentity.ForParameter(parameterInfo, type));
+        }
+        return CreateModelMetadata(type);
+    }
+
     private static void AddResponseContentTypes(IList<ApiResponseFormat> apiResponseFormats, IReadOnlyList<string> contentTypes)
     {
         foreach (var contentType in contentTypes)

src/Mvc/Mvc.ApiExplorer/test/EndpointMetadataApiDescriptionProviderTest.cs

@@ -385,12 +385,13 @@ public void AddsMultipleResponseFormatsFromMetadataWithAwaitableResultType()
         var apiDescription = GetApiDescription(
             [ProducesResponseType(typeof(InferredJsonClass), StatusCodes.Status201Created)]
         [ProducesResponseType(StatusCodes.Status400BadRequest)]
-        async Task<Results<Created<InferredJsonClass>, ProblemHttpResult>> () => {
-            await Task.CompletedTask;
-            return Random.Shared.Next() % 2 == 0
-                ? TypedResults.Created<InferredJsonClass>("/", new InferredJsonClass())
-                : TypedResults.Problem();
-        });
+        async Task<Results<Created<InferredJsonClass>, ProblemHttpResult>> () =>
+            {
+                await Task.CompletedTask;
+                return Random.Shared.Next() % 2 == 0
+                    ? TypedResults.Created<InferredJsonClass>("/", new InferredJsonClass())
+                    : TypedResults.Problem();
+            });
 
         Assert.Equal(2, apiDescription.SupportedResponseTypes.Count);
 
@@ -706,6 +707,16 @@ public void SupportsRequiredMembersInAsParametersAttribute()
             param => Assert.False(param.IsRequired));
     }
 
+    [Fact]
+    public void SupportsContainerTypeInAsParametersAttribute()
+    {
+        var apiDescription = GetApiDescription(([AsParameters] AsParametersWithRequiredMembers foo) => { });
+        Assert.Equal(4, apiDescription.ParameterDescriptions.Count);
+
+        Assert.NotNull(apiDescription.ParameterDescriptions[0].ModelMetadata.ContainerType);
+        Assert.Equal(typeof(AsParametersWithRequiredMembers), apiDescription.ParameterDescriptions[0].ModelMetadata.ContainerType);
+    }
+
 #nullable disable
     public class AsParametersWithRequiredMembersObliviousContext
     {