Add test source import related script and document.

This commit changes Unity test build to use PlayMode test of Unity player
instead of hand-made test suite with source code import.

Author: yfakariya

test/MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop/.gitignore

@@ -0,0 +1 @@
+/[Aa]ssets/

test/MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop/MakeAssets.ps1

@@ -0,0 +1,62 @@
+Remove-Item ./Assets -Force -Recurse
+
+if (!(Test-Path ./bin/Debug/MsgPack.dll))
+{
+    Write-Error "Build MsgPack.UnitTest.Unity.Full.Desktop project with Debug configuration first."
+    exit 1
+}
+
+[string[]]$additionalDefines = ("#define AOT", "#define NET35")
+[xml]$csproj = Get-Content ./MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop.csproj
+foreach($c in $csproj.Project.ItemGroup.Compile)
+{
+    if ($c.Include -eq $null)
+    {
+        continue
+    }
+
+    if ($c.Link -ne $null)
+    {
+        $destination = "Assets/UnitTests/$($c.Link)"
+    }
+    else
+    {
+        $destination = "Assets/UnitTests/$($c.Include)"
+    }
+
+    $destinationDirectory = [IO.Path]::GetDirectoryName($destination);
+    if (!(Test-Path $destinationDirectory))
+    {
+        New-Item $destinationDirectory -ItemType Directory | Out-Null
+    }
+
+    Copy-Item $c.Include $destination -Force
+
+    if ($destination.EndsWith(".cs"))
+    {
+        $code = [IO.File]::ReadAllLines($destination)
+        [IO.File]::WriteAllLines($destination, "#define UNITY")
+        [IO.File]::AppendAllLines($destination, $additionalDefines)
+
+        # Change "protected internal" to "protected" because Unity build drop is not "InternalsVisibleTo" target.
+        if ($destination.Contains("gen35") -or $destination.Contains("AutoMessagePackSerializerTest.Types.cs") -or $destination.Contains("RegressionTests.cs") -or $destination.Contains("SerializationContextTest.cs"))
+        {
+            $appender = [IO.File]::AppendText($destination)
+
+            foreach($line in $code)
+            {
+                $appender.WriteLine($line.Replace("protected internal", "protected"))
+            }
+
+            $appender.Flush()
+            $appender.Dispose()
+        }
+        else
+        {
+            [IO.File]::AppendAllLines($destination, $code)           
+        }
+    }
+}
+
+New-Item ./Assets/Dll -ItemType Directory | Out-Null
+Copy-Item ./bin/Debug/MsgPack.dll ./Assets/Dll/MsgPack.dll -Force

test/MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop/MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop.csproj

@@ -791,12 +791,6 @@
     <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
-  <PropertyGroup>
-    <PostBuildEvent Condition="'$(OS)' == 'Windows_NT'">RoboCopy $(ProjectDir)$(OutDir) $(ProjectDir)\..\MsgPack.UnitTest.Unity.Il2cpp.Full\Assets\Plugins\Dlls\ *.dll /MIR
-if %25ERRORLEVEL%25 geq 8 exit 1
-exit 0</PostBuildEvent>
-    <PostBuildEvent Condition="'$(OS)' != 'Windows_NT'">rsync -a -r --delete $(ProjectDir)$(OutDir)/*.dll $(ProjectDir)/../MsgPack.UnitTest.Unity.Il2cpp.Full/Assets/Plugins/Dlls/</PostBuildEvent>
-  </PropertyGroup>
   <!-- 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">

test/MsgPack.UnitTest.Unity.Il2cpp.Full/ProjectSettings/EditorBuildSettings.asset

@@ -4,11 +4,31 @@ MessagePack for CLI Unit Test for Unity IL2CPP
 Overview
 ---
 This directory contains unit test framework for Unity IL2CPP backend.
-The idea of the framework borrowed from UniRx, and many codes are based on UniRx unit testing.
 
 How to build
 ---
 
- 1. Open MsgPack.UnitTest.Unity.Il2cpp.Full.sln first (specifically, you need to build MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop project).
- 2. Build all. Three dlls (MsgPack.dll, MsgPack.UnitTest.dll, nunitlite.dll) will be copied to Assets/Plugins/Dlls
- 3. Open this directory in Unity Editor.
+1. Go to `../MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop` directory.
+2. Run `MakeAssets.ps1` PowerShell script (it may work on PowerShell Core)
+3. Ensure `../MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop/Assets` directory and its subtree have been generated.
+4. Open this folder with Unity.
+5. Import `../MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop/Assets/Dll` directory into `Assets` of Unity project with Unity Editor.
+6. Import `../MsgPack.UnitTest.Unity.Il2cpp.Full.Desktop/Assets/UnitTests` directory into `Assets` of Unity project with Unity Editor.
+
+How to run
+---
+
+See [Unity official document](https://docs.unity3d.com/Manual/testing-editortestsrunner.html) for details.
+
+1. Select [[Window]] > [[Unit Test Runner]]
+2. Click [[PlayMode]] tab.
+    * If you see [[Enable playmode tests]] button, click it and then restart the Unity editor.
+3. Ensure one more unit tests are shown in the dialog.
+4. Click [[Run all]] to run in the Editor.
+5. Open [[Build Settings]] dialog, and select a platform you want to run tests.
+    * Note that author only tests in iOS (AOT).
+6. Click [[Run all in player ({YourSelectedPlatform})]] button to run tests in play-mode.
+    * If you face an error that the editor cannot find scene file, do following:
+        1. Ensure that auto generated scene (its name should be "InitTestScene{RandomNumber}").
+        2. In [[Build Settings]] dialog, click [[Add Open Scenes]] and check *only* above auto generated scene.
+        3. Click [[Build and Run]] (or [[Build]] and then run the player built).