feature: add Android unit tests (#2201)

* Add Android tests

* Deploy Android unit tests in solution

* Fix memory leak in PocoObservableForPropertyTests amd make tests more robust

.gitignore

@@ -359,4 +359,7 @@ src/*.Tests/**/ApiApprovalTests*.received.txt
 .idea/
 
 # Fody Weavers (for tests)
-src/Tools/
+src/Tools/
+
+# Android auto-generated Resource file
+src/ReactiveUI.Android.Tests/Resources/Resource.[Dd]esigner.cs

src/ReactiveUI.Android.Tests/Assets/AboutAssets.txt

@@ -0,0 +1,19 @@
+Any raw assets you want to be deployed with your application can be placed in
+this directory (and child directories) and given a Build Action of "AndroidAsset".
+
+These files will be deployed with your package and will be accessible using Android's
+AssetManager, like this:
+
+public class ReadAsset : Activity
+{
+    protected override void OnCreate (Bundle bundle)
+    {
+        base.OnCreate (bundle);
+
+        InputStream input = Assets.Open ("my_asset.txt");
+    }
+}
+
+Additionally, some Android functions will automatically load asset files:
+
+Typeface tf = Typeface.CreateFromAsset (Context.Assets, "fonts/samplefont.ttf");

src/ReactiveUI.Android.Tests/Assets/xunit.runner.json

@@ -0,0 +1,5 @@
+{
+    "diagnosticMessages": true,
+    "longRunningTestSeconds": 30,
+    "methodDisplay": "classAndMethod"
+}

src/ReactiveUI.Android.Tests/MainActivity.cs

@@ -0,0 +1,41 @@
+// Copyright (c) 2019 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using System;
+using System.Reflection;
+using Android.App;
+using Android.Content;
+using Android.Runtime;
+using Android.Views;
+using Android.Widget;
+using Android.OS;
+
+using Xunit.Sdk;
+using Xunit.Runners.UI;
+
+namespace Splat.Android.Tests
+{
+    /// <summary>
+    /// Unit Test Runner Activity.
+    /// </summary>
+    // ReSharper disable UnusedMember.Global
+    [Activity(Label = "xUnit Android Runner", MainLauncher = true, Theme = "@android:style/Theme.Material.Light")]
+    public class MainActivity : RunnerActivity
+
+    // ReSharper restore UnusedMember.Global
+    {
+        /// <inheritdoc/>
+        protected override void OnCreate(Bundle bundle)
+        {
+            Locator.CurrentMutable.RegisterPlatformBitmapLoader();
+            AddExecutionAssembly(typeof(ExtensibilityPointFactory).Assembly);
+
+            AddTestAssembly(typeof(ReactiveUI.Tests.RxAppTest).Assembly);
+
+            // you cannot add more assemblies once calling base
+            base.OnCreate(bundle);
+        }
+    }
+}

src/ReactiveUI.Android.Tests/Properties/AndroidManifest.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="ReactiveUI.Android.Tests" android:versionCode="1" android:versionName="1.0" android:installLocation="preferExternal">
+  <uses-sdk android:minSdkVersion="19" android:targetSdkVersion="28" />
+  <application android:label="Splat.Android.Tests" android:icon="@drawable/Icon"></application>
+</manifest>

src/ReactiveUI.Android.Tests/Properties/AssemblyInfo.cs

@@ -0,0 +1,21 @@
+// Copyright (c) 2019 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using System.Reflection;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+
+// General Information about an assembly is controlled through the following
+// set of attributes. Change these attribute values to modify the information
+// associated with an assembly.
+[assembly: AssemblyTitle("ReactiveUI.Android.Tests")]
+[assembly: AssemblyDescription("")]
+[assembly: AssemblyConfiguration("")]
+[assembly: AssemblyCompany("")]
+[assembly: AssemblyProduct("ReactiveUI.Android.Tests")]
+[assembly: AssemblyCopyright("Copyright ©  2019")]
+[assembly: AssemblyTrademark("")]
+[assembly: AssemblyCulture("")]
+[assembly: ComVisible(false)]

src/ReactiveUI.Android.Tests/ReactiveUI.Android.Tests.csproj

@@ -0,0 +1,96 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="15.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProductVersion>8.0.30703</ProductVersion>
+    <SchemaVersion>2.0</SchemaVersion>
+    <ProjectGuid>{CBF8E93D-A2EA-4692-8087-B3655A35B0C0}</ProjectGuid>
+    <ProjectTypeGuids>{EFBA0AD7-5A72-4C68-AF49-83D382785DCF};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
+    <TemplateGuid>{122416d6-6b49-4ee2-a1e8-b825f31c79fe}</TemplateGuid>
+    <OutputType>Library</OutputType>
+    <AppDesignerFolder>Properties</AppDesignerFolder>
+    <RootNamespace>ReactiveUI.Android.Tests</RootNamespace>
+    <AssemblyName>ReactiveUI.Android.Tests</AssemblyName>
+    <FileAlignment>512</FileAlignment>
+    <AndroidApplication>True</AndroidApplication>
+    <AndroidResgenFile>Resources\Resource.designer.cs</AndroidResgenFile>
+    <AndroidResgenClass>Resource</AndroidResgenClass>
+    <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
+    <AndroidUseLatestPlatformSdk>false</AndroidUseLatestPlatformSdk>
+    <TargetFrameworkVersion>v9.0</TargetFrameworkVersion>
+    <AndroidManifest>Properties\AndroidManifest.xml</AndroidManifest>
+    <MonoAndroidResourcePrefix>Resources</MonoAndroidResourcePrefix>
+    <MonoAndroidAssetsPrefix>Assets</MonoAndroidAssetsPrefix>
+    <AndroidEnableSGenConcurrent>true</AndroidEnableSGenConcurrent>
+    <AndroidUseAapt2>true</AndroidUseAapt2>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DebugSymbols>True</DebugSymbols>
+    <DebugType>Full</DebugType>
+    <Optimize>False</Optimize>
+    <OutputPath>bin\Debug\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <AndroidUseSharedRuntime>True</AndroidUseSharedRuntime>
+    <AndroidLinkMode>None</AndroidLinkMode>
+    <EmbedAssembliesIntoApk>False</EmbedAssembliesIntoApk>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DebugSymbols>True</DebugSymbols>
+    <DebugType>PdbOnly</DebugType>
+    <Optimize>True</Optimize>
+    <OutputPath>bin\Release\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <AndroidManagedSymbols>true</AndroidManagedSymbols>
+    <AndroidUseSharedRuntime>False</AndroidUseSharedRuntime>
+    <AndroidLinkMode>SdkOnly</AndroidLinkMode>
+    <EmbedAssembliesIntoApk>True</EmbedAssembliesIntoApk>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="System" />
+    <Reference Include="System.Core" />
+    <Reference Include="Mono.Android" />
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="MainActivity.cs" />
+    <Compile Include="Resources\Resource.designer.cs" />
+    <Compile Include="Properties\AssemblyInfo.cs" />
+    <AdditionalFiles Include="..\stylecop.json">
+      <Link>stylecop.json</Link>
+    </AdditionalFiles>
+    <None Include="Resources\AboutResources.txt" />
+    <None Include="Properties\AndroidManifest.xml" />
+    <None Include="Assets\AboutAssets.txt" />
+    <AndroidAsset Include="Assets\xunit.runner.json" />
+    <AndroidResource Include="Resources\layout\Main.axml" />
+    <AndroidResource Include="Resources\values\Strings.xml" />
+    <AndroidResource Include="Resources\drawable\Icon.png" />
+  </ItemGroup>
+  <ItemGroup>
+    <PackageReference Include="xunit.runner.devices">
+      <Version>2.*</Version>
+    </PackageReference>
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\ReactiveUI.Tests\ReactiveUI.Tests.csproj">
+      <Project>{2ade0a50-5012-4341-8f4f-97597c2d6920}</Project>
+      <Name>ReactiveUI.Tests</Name>
+    </ProjectReference>
+    <ProjectReference Include="..\ReactiveUI\ReactiveUI.csproj">
+      <Project>{464cb812-f99f-401b-be4c-e8f0515cd19d}</Project>
+      <Name>ReactiveUI</Name>
+    </ProjectReference>
+  </ItemGroup>
+  <Import Project="$(MSBuildExtensionsPath)\Xamarin\Android\Xamarin.Android.CSharp.targets" />
+  <!-- To modify your build process, add your task inside one of the targets below and uncomment it.
+    Other similar extension points exist, see Microsoft.Common.targets.
+    <Target Name="BeforeBuild">
+    </Target>
+    <Target Name="AfterBuild">
+    </Target>
+  -->
+</Project>

src/ReactiveUI.Android.Tests/Resources/AboutResources.txt

@@ -0,0 +1,44 @@
+Images, layout descriptions, binary blobs and string dictionaries can be included 
+in your application as resource files.  Various Android APIs are designed to 
+operate on the resource IDs instead of dealing with images, strings or binary blobs 
+directly.
+
+For example, a sample Android app that contains a user interface layout (main.xml),
+an internationalization string table (strings.xml) and some icons (drawable-XXX/icon.png) 
+would keep its resources in the "Resources" directory of the application:
+
+Resources/
+    drawable/
+        icon.png
+
+    layout/
+        main.xml
+
+    values/
+        strings.xml
+
+In order to get the build system to recognize Android resources, set the build action to
+"AndroidResource".  The native Android APIs do not operate directly with filenames, but 
+instead operate on resource IDs.  When you compile an Android application that uses resources, 
+the build system will package the resources for distribution and generate a class called "R" 
+(this is an Android convention) that contains the tokens for each one of the resources 
+included. For example, for the above Resources layout, this is what the R class would expose:
+
+public class R {
+    public class drawable {
+        public const int icon = 0x123;
+    }
+
+    public class layout {
+        public const int main = 0x456;
+    }
+
+    public class strings {
+        public const int first_string = 0xabc;
+        public const int second_string = 0xbcd;
+    }
+}
+
+You would then use R.drawable.icon to reference the drawable/icon.png file, or R.layout.main 
+to reference the layout/main.xml file, or R.strings.first_string to reference the first 
+string in the dictionary file values/strings.xml.

src/ReactiveUI.Android.Tests/Resources/layout/Main.axml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:orientation="vertical"
+    android:layout_width="fill_parent"
+    android:layout_height="fill_parent"
+    >
+<Button  
+    android:id="@+id/MyButton"
+    android:layout_width="fill_parent" 
+    android:layout_height="wrap_content" 
+    android:text="@string/Hello"
+    />
+</LinearLayout>

src/ReactiveUI.Android.Tests/Resources/values/Strings.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="Hello">Hello World, Click Me!</string>
+    <string name="ApplicationName">ReactiveUI.Android.Tests</string>
+</resources>

src/ReactiveUI.Tests/Locator/DefaultViewLocatorTests.cs

@@ -220,7 +220,7 @@ public void NoErrorIsRaisedIfATypeCannotBeFound()
             using (resolver.WithResolver())
             {
                 var fixture = new DefaultViewLocator();
-                fixture.ViewModelToViewFunc = viewModelName => "DoesNotExist";
+                fixture.ViewModelToViewFunc = viewModelName => "DoesNotExist, " + typeof(DefaultViewLocatorTests).Assembly.FullName;
                 var vm = new FooViewModel();
 
                 var result = fixture.ResolveView(vm);

src/ReactiveUI.Tests/ReactiveUI.Tests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="MSBuild.Sdk.Extras">
 
   <PropertyGroup>    
-    <TargetFrameworks>netcoreapp2.0</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;netcoreapp2.0</TargetFrameworks>
     <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);net461;netcoreapp3.0</TargetFrameworks>
     <LangVersion>latest</LangVersion>
   </PropertyGroup>