From 22ebe38f70c038ef89ce8f1453ece5d222e685a8 Mon Sep 17 00:00:00 2001
From: Stephane Delcroix <stephane@delcroix.org>
Date: Thu, 2 Feb 2017 15:28:59 +0100
Subject: [PATCH] [Xaml] do not set properties with private setters (#717)

---
 Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml   |  9 ++++
 .../Issues/Bz44216.xaml.cs                         | 58 ++++++++++++++++++++++
 Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs       | 20 +++++++-
 3 files changed, 85 insertions(+), 2 deletions(-)
 create mode 100644 Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml
 create mode 100644 Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml.cs

diff --git a/Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml b/Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml
new file mode 100644
index 0000000..fd0cfb4
--- /dev/null
+++ b/Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml
@@ -0,0 +1,9 @@
+<?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.Bz44216">
+	<ContentPage.Behaviors>
+		<local:Bz44216Behavior MinLengh="5" />
+	</ContentPage.Behaviors>
+</ContentPage>
diff --git a/Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml.cs b/Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml.cs
new file mode 100644
index 0000000..b6ad87b
--- /dev/null
+++ b/Xamarin.Forms.Xaml.UnitTests/Issues/Bz44216.xaml.cs
@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using NUnit.Framework;
+using Xamarin.Forms;
+using Xamarin.Forms.Core.UnitTests;
+
+namespace Xamarin.Forms.Xaml.UnitTests
+{
+	public class Bz44216Behavior : Behavior<ContentPage>
+	{
+		static readonly BindableProperty MinLenghProperty = BindableProperty.Create("MinLengh", typeof(int), typeof(Bz44216Behavior), 1);
+
+		public int MinLengh {
+			get { return (int)base.GetValue(MinLenghProperty); }
+			private set { base.SetValue(MinLenghProperty, value > 0 ? value : 1); }
+		}
+	}
+
+	[XamlCompilation(XamlCompilationOptions.Skip)]
+	public partial class Bz44216 : ContentPage
+	{
+		public Bz44216()
+		{
+			InitializeComponent();
+		}
+
+		public Bz44216(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 DonSetValueOnPrivateBP(bool useCompiledXaml)
+			{
+				if (useCompiledXaml)
+					Assert.Throws(new XamlParseExceptionConstraint(7, 26, s => s.StartsWith("No property,", StringComparison.Ordinal)), () => MockCompiler.Compile(typeof(Bz44216)));
+				else
+					Assert.Throws(new XamlParseExceptionConstraint(7, 26, s=> s.StartsWith("Cannot assign property", StringComparison.Ordinal)), () => new Bz44216(useCompiledXaml));
+			}
+		}
+	}
+}
diff --git a/Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs b/Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs
index 3ea1d1c..833d5d9 100644
--- a/Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs
+++ b/Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs
@@ -297,7 +297,7 @@ namespace Xamarin.Forms.Xaml
 				return;
 
 			//If we can assign that value to a normal property, let's do it
-			if (xpe == null && TrySetProperty(xamlelement, localName, value, lineInfo, serviceProvider, out xpe))
+			if (xpe == null && TrySetProperty(xamlelement, localName, value, lineInfo, serviceProvider, context, out xpe))
 				return;
 
 			//If it's an already initialized property, add to it
@@ -423,7 +423,7 @@ namespace Xamarin.Forms.Xaml
 			return false;
 		}
 
-		static bool TrySetProperty(object element, string localName, object value, IXmlLineInfo lineInfo, XamlServiceProvider serviceProvider, out Exception exception)
+		static bool TrySetProperty(object element, string localName, object value, IXmlLineInfo lineInfo, XamlServiceProvider serviceProvider, HydratationContext context, out Exception exception)
 		{
 			exception = null;
 
@@ -433,6 +433,9 @@ namespace Xamarin.Forms.Xaml
 			if (propertyInfo == null || !propertyInfo.CanWrite || (setter = propertyInfo.SetMethod) == null)
 				return false;
 
+			if (!IsVisibleFrom(setter, context.RootElement))
+				return false;
+
 			object convertedValue = value.ConvertTo(propertyInfo.PropertyType, () => propertyInfo, serviceProvider);
 			if (convertedValue != null && !propertyInfo.PropertyType.IsInstanceOfType(convertedValue))
 				return false;
@@ -441,6 +444,19 @@ namespace Xamarin.Forms.Xaml
 			return true;
 		}
 
+		static bool IsVisibleFrom(MethodInfo setter, object rootElement)
+		{
+			if (setter.IsPublic)
+				return true;
+			if (setter.IsPrivate && setter.DeclaringType == rootElement.GetType())
+				return true;
+			if ((setter.IsAssembly || setter.IsFamilyOrAssembly) && setter.DeclaringType.AssemblyQualifiedName == rootElement.GetType().AssemblyQualifiedName)
+				return true;
+			if (setter.IsFamily && setter.DeclaringType.IsAssignableFrom(rootElement.GetType()))
+				return true;
+			return false;
+		}
+
 		static bool TryAddToProperty(object element, string localName, object value, IXmlLineInfo lineInfo, XamlServiceProvider serviceProvider, out Exception exception)
 		{
 			exception = null;
-- 
2.7.4