Add test for nested calls

Author: JsonFreeman

src/services/signatureHelp.ts

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft. All rights reserved. Licensed under the Apache License, Version 2.0. 
 // See LICENSE.txt in the project root for complete license information.
 
-///<reference path='references.ts' />
+///<reference path='services.ts' />
 
 module ts.SignatureHelp {
 

tests/cases/fourslash/signatureHelpOnNestedOverloads.ts

@@ -0,0 +1,20 @@
+/// <reference path='fourslash.ts'/>
+
+////declare function fn(x: string);
+////declare function fn(x: string, y: number);
+////declare function fn2(x: string);
+////declare function fn2(x: string, y: number);
+////fn('', fn2(/*1*/
+
+goTo.marker('1');
+verify.signatureHelpCountIs(2);
+verify.currentSignatureHelpIs("fn2(x: string): any");
+verify.currentParameterHelpArgumentNameIs("x");
+verify.currentParameterSpanIs("x: string");
+
+edit.insert("'',");
+
+verify.signatureHelpCountIs(2);
+// verify.currentSignatureHelpIs("fn2(x: string, y: number): any");
+// verify.currentParameterHelpArgumentNameIs("y");
+// verify.currentParameterSpanIs("y: number");