Add fix for SendEvent causing test to fail (#195)

Add flag in ServiceHost to ignore SendEvent errors

src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/ProtocolEndpoint.cs

@@ -9,6 +9,7 @@ using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.SqlTools.ServiceLayer.Hosting.Protocol.Channel;
 using Microsoft.SqlTools.ServiceLayer.Hosting.Protocol.Contracts;
+using Microsoft.SqlTools.ServiceLayer.Utility;
 
 namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol
 {
@@ -28,6 +29,14 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol
         private Dictionary<string, TaskCompletionSource<Message>> pendingRequests =
             new Dictionary<string, TaskCompletionSource<Message>>();
 
+        /// <summary>
+        /// When true, SendEvent will ignore exceptions and write them
+        /// to the log instead. Intended to be used for test scenarios
+        /// where SendEvent throws exceptions unrelated to what is
+        /// being tested.
+        /// </summary>
+        internal static bool SendEventIgnoreExceptions = false;
+
         /// <summary>
         /// Gets the MessageDispatcher which allows registration of
         /// handlers for requests, responses, and events that are
@@ -193,6 +202,8 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol
         public Task SendEvent<TParams>(
             EventType<TParams> eventType,
             TParams eventParams)
+        {
+            try
             {
                 if (!this.protocolChannel.IsConnected)
                 {
@@ -226,6 +237,19 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol
                         eventParams);
                 }
             }
+            catch (Exception ex)
+            {
+                if (SendEventIgnoreExceptions)
+                {
+                    Logger.Write(LogLevel.Verbose, "Exception in SendEvent " + ex.ToString());
+                }
+                else
+                {
+                    throw;
+                }
+            }
+            return Task.FromResult(false);
+        }
 
         #endregion
 

test/Microsoft.SqlTools.ServiceLayer.Test/LanguageServer/LanguageServiceTests.cs

@@ -3,7 +3,6 @@
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 //
 
-using Microsoft.SqlServer.Management.SqlParser.Parser;
 using Microsoft.SqlTools.ServiceLayer.Connection;
 using Microsoft.SqlTools.ServiceLayer.LanguageServices;
 using Microsoft.SqlTools.ServiceLayer.LanguageServices.Completion;
@@ -290,6 +289,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.LanguageServer
         {
             // When we make a connection to a live database
             ScriptFile scriptFile;
+            Hosting.ServiceHost.SendEventIgnoreExceptions = true;
             ConnectionInfo connInfo = TestObjects.InitLiveConnectionInfo(out scriptFile);
 
             // And we place the cursor after a function that should prompt for signature help
@@ -308,12 +308,15 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.LanguageServer
                 }
             };
 
-            // If we have a valid ScriptParseInfo and the SQL has already been parsed
+            // If the SQL has already been parsed
             var service = LanguageService.Instance;
-            ScriptParseInfo parseInfo = service.GetScriptParseInfo(scriptFile.ClientFilePath);
             await service.UpdateLanguageServiceOnConnection(connInfo);
 
-            // We should get back a non-null SignatureHelp 
+            // We should get back a non-null ScriptParseInfo
+            ScriptParseInfo parseInfo = service.GetScriptParseInfo(scriptFile.ClientFilePath);
+            Assert.NotNull(parseInfo);
+
+            // And we should get back a non-null SignatureHelp
             SignatureHelp signatureHelp = service.GetSignatureHelp(textDocument, scriptFile);
             Assert.NotNull(signatureHelp);
         }