Add unittest [WIP]

Wox.Test/Plugins/PluginInitTest.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using Moq;
+using NUnit.Framework;
+using Wox.Core.Exception;
+using Wox.Core.Plugin;
+using Wox.Plugin;
+
+namespace Wox.Test.Plugins
+{
+
+    [TestFixture]
+    public class PluginInitTest
+    {
+        [Test]
+        public void CouldNotFindUserProfileTest()
+        {
+            var api = new Mock<IPublicAPI>();
+            Environment.SetEnvironmentVariable("USERPROFILE", "");
+            Assert.Throws(typeof(WoxCritialException), () => PluginManager.Init(api.Object));
+        }
+
+        [Test]
+        public void PublicAPIIsNullTest()
+        {
+            Assert.Throws(typeof(WoxCritialException), () => PluginManager.Init(null));
+        }
+    }
+}