Fix schema compare script formatting (#809)

* Add GO after each statement and remove leading and trailing whitespace

* Addressing comments

* formatting

src/Microsoft.SqlTools.ServiceLayer/SchemaCompare/SchemaCompareOperation.cs

@@ -160,13 +160,13 @@ namespace Microsoft.SqlTools.ServiceLayer.SchemaCompare
                 {
                     string sourceScript;
                     difference.SourceObject.TryGetScript(out sourceScript);
-                    diffEntry.SourceScript = RemoveExcessWhitespace(sourceScript);
+                    diffEntry.SourceScript = FormatScript(sourceScript);
                 }
                 if (difference.TargetObject != null)
                 {
                     string targetScript;
                     difference.TargetObject.TryGetScript(out targetScript);
-                    diffEntry.TargetScript = RemoveExcessWhitespace(targetScript);
+                    diffEntry.TargetScript = FormatScript(targetScript);
                 }
             }
 
@@ -210,10 +210,26 @@ namespace Microsoft.SqlTools.ServiceLayer.SchemaCompare
             return ConnectionService.BuildConnectionString(connInfo.ConnectionDetails);
         }
 
-        private static string RemoveExcessWhitespace(string script)
+        public static string RemoveExcessWhitespace(string script)
         {
+            if (script != null)
+            {
+                // remove leading and trailing whitespace
+                script = script.Trim();
                 // replace all multiple spaces with single space
-            return Regex.Replace(script, " {2,}", " ");
+                script = Regex.Replace(script, " {2,}", " ");
+            }
+            return script;
+        }
+
+        public static string FormatScript(string script)
+        {
+            script = RemoveExcessWhitespace(script);
+            if (!string.IsNullOrWhiteSpace(script) && !script.Equals("null"))
+            {
+                script += Environment.NewLine + "GO";
+            }
+            return script;
         }
 
         private static string GetName(string name)

test/Microsoft.SqlTools.ServiceLayer.UnitTests/SchemaCompare/SchemaCompareTests.cs

@@ -0,0 +1,89 @@
+//
+// 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 Microsoft.SqlTools.ServiceLayer.SchemaCompare;
+using Xunit;
+
+namespace Microsoft.SqlTools.ServiceLayer.UnitTests.SchemaCompare
+{
+    public class SchemaCompareTests
+    {
+        [Fact]
+        public void FormatScriptAddsGo()
+        {
+            string script = "EXECUTE sp_addextendedproperty @name = N'MS_Description', @value = N'Primary key for AWBuildVersion records.', @level0type = N'SCHEMA', @level0name = N'dbo', @level1type = N'TABLE', @level1name = N'AWBuildVersion', @level2type = N'COLUMN', @level2name = N'SystemInformationID';";
+            Assert.DoesNotContain("GO", script);
+            string result = SchemaCompareOperation.FormatScript(script);
+            Assert.EndsWith("GO", result);
+        }
+
+        [Fact]
+        public void FormatScriptDoesNotAddGoForNullScripts()
+        {
+            string script1 = null;
+            string result1 = SchemaCompareOperation.FormatScript(script1);
+            Assert.DoesNotContain("GO", result1);
+            Assert.Equal(null, result1);
+
+            string script2 = "null";
+            string result2 = SchemaCompareOperation.FormatScript(script2);
+            Assert.DoesNotContain("GO", result2);
+        }
+
+        [Fact]
+        public void FormatScriptDoesNotAddGoForEmptyStringScripts()
+        {
+            string script = string.Empty;
+            string result = SchemaCompareOperation.FormatScript(script);
+            Assert.DoesNotContain("GO", result);
+            Assert.Equal(string.Empty, result);
+        }
+
+        [Fact]
+        public void FormatScriptDoesNotAddGoForWhitespaceStringScripts()
+        {
+            string script = "    \t\n";
+            Assert.True(string.IsNullOrWhiteSpace(script));
+            string result = SchemaCompareOperation.FormatScript(script);
+            Assert.DoesNotContain("GO", result);
+            Assert.Equal(string.Empty, result);
+        }
+
+        [Fact]
+        public void RemovesExcessWhitespace()
+        {
+            // leading whitespace
+            string script1 = "\r\n   EXECUTE sp_addextendedproperty @name = N'MS_Description', @value = N'Primary key for AWBuildVersion records.', @level0type = N'SCHEMA', @level0name = N'dbo', @level1type = N'TABLE', @level1name = N'AWBuildVersion', @level2type = N'COLUMN', @level2name = N'SystemInformationID';";
+            string result1 = SchemaCompareOperation.RemoveExcessWhitespace(script1);
+            Assert.False(script1.Equals(result1));
+            Assert.False(result1.StartsWith("\r"));
+            Assert.True(result1.StartsWith("EXECUTE"));
+
+            // trailing whitespace
+            string script2 = "EXECUTE sp_addextendedproperty @name = N'MS_Description', @value = N'Primary key for AWBuildVersion records.', @level0type = N'SCHEMA', @level0name = N'dbo', @level1type = N'TABLE', @level1name = N'AWBuildVersion', @level2type = N'COLUMN', @level2name = N'SystemInformationID';  \n";
+            string result2 = SchemaCompareOperation.RemoveExcessWhitespace(script2);
+            Assert.False(script2.Equals(result2));
+            Assert.False(result2.EndsWith("\n"));
+            Assert.True(result2.EndsWith(";"));
+
+            // non-leading/trailing multiple spaces
+            string script3 = @"CREATE TABLE [dbo].[AWBuildVersion] (
+     [SystemInformationID] TINYINT IDENTITY (1, 1) NOT NULL,
+ [Database Version] NVARCHAR (25)     NOT NULL,
+ [VersionDate] DATETIME     NOT NULL,
+ [ModifiedDate] DATETIME NOT NULL
+);";
+            string expected3 = @"CREATE TABLE [dbo].[AWBuildVersion] (
+ [SystemInformationID] TINYINT IDENTITY (1, 1) NOT NULL,
+ [Database Version] NVARCHAR (25) NOT NULL,
+ [VersionDate] DATETIME NOT NULL,
+ [ModifiedDate] DATETIME NOT NULL
+);";
+            string result3 = SchemaCompareOperation.RemoveExcessWhitespace(script3);
+            Assert.True(expected3.Equals(result3));
+        }
+    }
+}