Add test for goto def

src/harness/fourslash.ts

@@ -420,6 +420,9 @@ module FourSlash {
             this.activeFile = fileToOpen;
             var fileName = fileToOpen.fileName.replace(Harness.IO.directoryName(fileToOpen.fileName), '').substr(1);
             this.scenarioActions.push('<OpenFile FileName="" SrcFileId="' + fileName + '" FileId="' + fileName + '" />');
+            
+            // Let the host know that this file is now open
+            this.languageServiceAdapterHost.openFile(fileToOpen.fileName);
         }
 
         public verifyErrorExistsBetweenMarkers(startMarkerName: string, endMarkerName: string, negative: boolean) {

src/harness/harnessLanguageService.ts

@@ -154,6 +154,9 @@ module Harness.LanguageService {
             throw new Error("No script with name '" + fileName + "'");
         }
 
+        public openFile(fileName: string): void {
+        }
+
         /**
           * @param line 1 based index
           * @param col 1 based index
@@ -442,8 +445,8 @@ module Harness.LanguageService {
             this.client = client;
         }
 
-        addScript(fileName: string, content: string): void {
-            super.addScript(fileName, content);
+        openFile(fileName: string): void { 
+            super.openFile(fileName);
             this.client.openFile(fileName);
         }
 

src/server/client.ts

@@ -65,7 +65,7 @@ module ts.server {
         }
 
         stat(path: string, callback?: (err: any, stats: any) => any) {
-            throw new Error("Not implemented Yet.");
+            return 0;
         }
 
         lineColToPosition(fileName: string, line: number, col: number): number { 

tests/cases/fourslash/definition.ts

@@ -0,0 +1,12 @@
+/// <reference path='fourslash.ts'/>
+
+// @Filename: b.ts
+////import n = require('a/*1*/');
+////var x = new n.Foo();
+
+// @Filename: a.ts
+//// /*2*/export class Foo {}
+
+goTo.marker('1');
+goTo.definition();
+verify.caretAtMarker('2');