[XamlC] resolve generic types with generic and non-generic parameters (#1533)

fixes #1497

Xamarin.Forms.Build.Tasks/TypeReferenceExtensions.cs

@@ -326,8 +326,12 @@ namespace Xamarin.Forms.Build.Tasks
 				return self;
 
 			List<TypeReference> args = new List<TypeReference>();
-			for (var i = 0; i < genericself.GenericArguments.Count; i++)
-				args.Add(genericdeclType.GenericArguments[(genericself.GenericArguments[i] as GenericParameter).Position]);
+			for (var i = 0; i < genericself.GenericArguments.Count; i++) {
+				if (!genericself.GenericArguments[i].IsGenericParameter)
+					args.Add(genericself.GenericArguments[i]);
+				else
+					args.Add(genericdeclType.GenericArguments[(genericself.GenericArguments[i] as GenericParameter).Position]);
+			}
 			return self.GetElementType().MakeGenericInstanceType(args.ToArray());
 		}
 	}

Xamarin.Forms.Xaml.UnitTests/Issues/Gh1497.xaml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             xmlns:local="clr-namespace:Xamarin.Forms.Xaml.UnitTests"
+             x:Class="Xamarin.Forms.Xaml.UnitTests.Gh1497">
+    <Entry x:Name="entry">
+        <Entry.Behaviors>
+            <local:Gh1497EntryValidationBehavior x:TypeArguments="Entry"/>
+        </Entry.Behaviors>
+    </Entry>
+</ContentPage>

Xamarin.Forms.Xaml.UnitTests/Issues/Gh1497.xaml.cs

@@ -0,0 +1,50 @@
+using System;
+using NUnit.Framework;
+using Xamarin.Forms.Core.UnitTests;
+
+namespace Xamarin.Forms.Xaml.UnitTests
+{
+	abstract class Gh1497BaseValidationBehavior<TBindable, TModel> : Behavior<TBindable> where TBindable : BindableObject
+	{
+	}
+
+	sealed class Gh1497EntryValidationBehavior<TModel> : Gh1497BaseValidationBehavior<Entry, TModel>
+	{
+	}
+
+	public partial class Gh1497 : ContentPage
+	{
+		public Gh1497()
+		{
+			InitializeComponent();
+		}
+
+		public Gh1497(bool useCompiledXaml)
+		{
+			//this stub will be replaced at compile time
+		}
+
+		[TestFixture]
+		class Tests
+		{
+			[SetUp]
+			public void Setup()
+			{
+				Device.PlatformServices = new MockPlatformServices();
+			}
+
+			[TearDown]
+			public void TearDown()
+			{
+				Device.PlatformServices = null;
+			}
+
+			[TestCase(true), TestCase(false)]
+			public void GenericsIssue(bool useCompiledXaml)
+			{
+				var layout = new Gh1497(useCompiledXaml);
+				Assert.That(layout.entry.Behaviors[0], Is.TypeOf(typeof(Gh1497EntryValidationBehavior<Entry>)));
+			}
+		}
+	}
+}

Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj

@@ -564,6 +564,9 @@
     <Compile Include="InlineCSS.xaml.cs">
       <DependentUpon>InlineCSS.xaml</DependentUpon>
     </Compile>
+    <Compile Include="Issues\Gh1497.xaml.cs">
+      <DependentUpon>Gh1497.xaml</DependentUpon>
+    </Compile>
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <Import Project="..\.nuspec\Xamarin.Forms.Debug.targets" />
@@ -1004,6 +1007,9 @@
     <EmbeddedResource Include="Issues\Gh1346.xaml">
       <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
     </EmbeddedResource>
+    <EmbeddedResource Include="Issues\Gh1497.xaml">
+      <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
+    </EmbeddedResource>
   </ItemGroup>
   <ItemGroup>
     <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />

Xamarin.Forms.Xaml.UnitTests/XamlC/TypeReferenceExtensionsTests.cs

@@ -27,6 +27,14 @@ namespace Xamarin.Forms.Xaml.XamlcUnitTests
 		{
 		}
 
+		class Baz<T1, T2> : Foo<T1>
+		{
+		}
+
+		class Qux<T> : Baz<int, T>
+		{
+		}
+
 		ModuleDefinition module;
 
 		[SetUp]
@@ -96,6 +104,7 @@ namespace Xamarin.Forms.Xaml.XamlcUnitTests
 		[TestCase(typeof(Foo<string>), typeof(Foo), ExpectedResult = true)]
 		[TestCase(typeof(Bar<string>), typeof(Foo), ExpectedResult = true)]
 		[TestCase(typeof(Bar<string>), typeof(Foo<string>), ExpectedResult = true)]
+		[TestCase(typeof(Qux<string>), typeof(double), ExpectedResult = false)] //https://github.com/xamarin/Xamarin.Forms/issues/1497
 		public bool TestInheritsFromOrImplements(Type typeRef, Type baseClass)
 		{
 			return TypeReferenceExtensions.InheritsFromOrImplements(module.ImportReference(typeRef), module.ImportReference(baseClass));