Porting showplan code from ssms (#1280)

* Porting showplan code from ssms

* Moving showplans bits to a subfolder

* code cleanup

* Remvoing unnecssary conditional visibility

test/Microsoft.SqlTools.ServiceLayer.UnitTests/Microsoft.SqlTools.ServiceLayer.UnitTests.csproj

@@ -29,4 +29,8 @@
 	<ItemGroup>
 		<Service Include="{82a7f48d-3b50-4b1e-b82e-3ada8210c358}" />
 	</ItemGroup>
-</Project>
+	<ItemGroup>
+	    <Content Remove=".\ShowPlan\TestExecution.xml" />
+    	<EmbeddedResource Include=".\ShowPlan\TestExecutionPlan.xml" />
+	</ItemGroup>
+</Project>

test/Microsoft.SqlTools.ServiceLayer.UnitTests/ShowPlan/ShowPlanTests.cs

@@ -0,0 +1,32 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System;
+using System.IO;
+using System.Reflection;
+using System.Threading.Tasks;
+using NUnit.Framework;
+using Microsoft.SqlTools.ServiceLayer.ShowPlan.ShowPlanGraph;
+
+
+namespace Microsoft.SqlTools.ServiceLayer.UnitTests.ShowPlan
+{
+    public class ShowPlanXMLTests
+    {
+        [Test]
+        public async Task ParseXMLFileReturnsValidShowPlanGraph()
+        {
+            Assembly assembly = Assembly.GetAssembly(typeof(ShowPlanXMLTests));
+            Stream scriptStream = assembly.GetManifestResourceStream(assembly.GetName().Name + ".ShowPlan.TestExecutionPlan.xml");
+            StreamReader reader = new StreamReader(scriptStream);
+            string text = reader.ReadToEnd();
+            var showPlanGraphs = ShowPlanGraph.ParseShowPlanXML(text, ShowPlanType.Actual);
+            Assert.AreEqual(1, showPlanGraphs.Length, "Single show plan graph not generated from the test xml file");
+            var testShowPlanGraph = showPlanGraphs[0];
+            Assert.NotNull(testShowPlanGraph, "graph should not be null");
+            Assert.NotNull(testShowPlanGraph.Root, "graph should have a root");
+        }
+    }
+}