Added unit tests for the ViewDataTestPlugin.

Author: u.ashikov

test/MyTested.AspNetCore.Mvc.ViewData.Test/PluginsTests/ViewDataTestPluginTests.cs

@@ -0,0 +1,42 @@
+namespace MyTested.AspNetCore.Mvc.Test.PluginsTests
+{
+    using Microsoft.Extensions.DependencyInjection;
+    using Plugins;
+    using System;
+    using Xunit;
+
+    public class ViewDataTestPluginTests
+    {
+        [Fact]
+        public void ShouldHavePriorityWithDefaultValue()
+        {
+            var testPlugin = new ViewDataTestPlugin();
+
+            Assert.IsAssignableFrom<IDefaultRegistrationPlugin>(testPlugin);
+            Assert.NotNull(testPlugin);
+            Assert.Equal(-1000, testPlugin.Priority);
+        }
+
+        [Fact]
+        public void ShouldThrowArgumentNullExceptionWithInvalidServiceCollection()
+        {
+            var testPlugin = new ViewDataTestPlugin();
+
+            Assert.Throws<ArgumentNullException>(() => testPlugin.DefaultServiceRegistrationDelegate(null));
+        }
+
+        [Fact]
+        public void ShouldInvokeMethodOfTypeVoidWithValidServiceCollection()
+        {
+            var testPlugin = new ViewDataTestPlugin();
+            var serviceCollection = new ServiceCollection();
+
+            testPlugin.DefaultServiceRegistrationDelegate(serviceCollection);
+
+            var methodReturnType = testPlugin.DefaultServiceRegistrationDelegate.Method.ReturnType.Name;
+
+            Assert.True(methodReturnType == "Void");
+            Assert.True(serviceCollection.Count == 126);
+        }
+    }
+}