diff --git a/src/server/client.ts b/src/server/client.ts
index 1aa7547f541..aa1ddb34bf7 100644
--- a/src/server/client.ts
+++ b/src/server/client.ts
@@ -177,10 +177,11 @@ module ts.server {
 
         getCompletionsAtPosition(fileName: string, position: number): CompletionInfo {
             var lineCol = this.positionToOneBasedLineCol(fileName, position);
-            var args: ServerProtocol.CodeLocationRequestArgs = {
+            var args: ServerProtocol.CompletionsRequestArgs = {
                 file: fileName,
                 line: lineCol.line,
                 col: lineCol.col,
+                prefix: undefined
             };
 
             var request = this.processRequest<ServerProtocol.CompletionsRequest>(CommandNames.Completions, args);
diff --git a/tests/cases/fourslash/server/completions.ts b/tests/cases/fourslash/server/completions.ts
new file mode 100644
index 00000000000..82d3b5b2400
--- /dev/null
+++ b/tests/cases/fourslash/server/completions.ts
@@ -0,0 +1,17 @@
+/// <reference path='fourslash.ts'/>
+
+////var x: string[] = [];
+////x.forEach(function (y) { y/*1*/
+////x.forEach(y => y/*2*/
+
+goTo.marker('1');
+edit.insert('.');
+verify.memberListContains('trim');
+verify.memberListCount(20);
+edit.insert('});'); // need the following lines to not have parse errors in order for completion list to appear
+
+goTo.marker('2');
+edit.insert('.');
+verify.memberListContains('trim');
+verify.memberListCount(20);
+        
\ No newline at end of file