diff --git a/src/harness/fourslash.ts b/src/harness/fourslash.ts
index 84bf3bb1752..df870034270 100644
--- a/src/harness/fourslash.ts
+++ b/src/harness/fourslash.ts
@@ -1535,8 +1535,8 @@ Actual: ${stringify(fullActual)}`);
             const addSpanInfoString = () => {
                 if (previousSpanInfo) {
                     resultString += currentLine;
-                    let thisLineMarker = repeatString(startColumn, " ") + repeatString(length, "~");
-                    thisLineMarker += repeatString(this.alignmentForExtraInfo - thisLineMarker.length - prefixString.length + 1, " ");
+                    let thisLineMarker = ts.repeatString(" ", startColumn) + ts.repeatString("~", length);
+                    thisLineMarker += ts.repeatString(" ", this.alignmentForExtraInfo - thisLineMarker.length - prefixString.length + 1);
                     resultString += thisLineMarker;
                     resultString += "=> Pos: (" + (pos - length) + " to " + (pos - 1) + ") ";
                     resultString += " " + previousSpanInfo;
@@ -1551,7 +1551,7 @@ Actual: ${stringify(fullActual)}`);
                     if (resultString.length) {
                         resultString += "\n--------------------------------";
                     }
-                    currentLine = "\n" + nextLine.toString() + repeatString(3 - nextLine.toString().length, " ") + ">" + this.activeFile.content.substring(pos, fileLineMap[nextLine]) + "\n    ";
+                    currentLine = "\n" + nextLine.toString() + ts.repeatString(" ", 3 - nextLine.toString().length) + ">" + this.activeFile.content.substring(pos, fileLineMap[nextLine]) + "\n    ";
                     startColumn = 0;
                     length = 0;
                 }
@@ -2787,7 +2787,7 @@ Actual: ${stringify(fullActual)}`);
             const items = this.languageService.getNavigationBarItems(this.activeFile.fileName);
             Harness.IO.log(`Navigation bar (${items.length} items)`);
             for (const item of items) {
-                Harness.IO.log(`${repeatString(item.indent, " ")}name: ${item.text}, kind: ${item.kind}, childItems: ${item.childItems.map(child => child.text)}`);
+                Harness.IO.log(`${ts.repeatString(" ", item.indent)}name: ${item.text}, kind: ${item.kind}, childItems: ${item.childItems.map(child => child.text)}`);
             }
         }
 
@@ -3689,14 +3689,6 @@ ${code}
         };
     }
 
-    function repeatString(count: number, char: string) {
-        let result = "";
-        for (let i = 0; i < count; i++) {
-            result += char;
-        }
-        return result;
-    }
-
     function stringify(data: any, replacer?: (key: string, value: any) => any): string {
         return JSON.stringify(data, replacer, 2);
     }
diff --git a/src/services/formatting/formatting.ts b/src/services/formatting/formatting.ts
index 49fb1420db8..c020e638692 100644
--- a/src/services/formatting/formatting.ts
+++ b/src/services/formatting/formatting.ts
@@ -1277,13 +1277,13 @@ namespace ts.formatting {
             }
 
             if (internedTabsIndentation[tabs] === undefined) {
-                internedTabsIndentation[tabs] = tabString = repeat("\t", tabs);
+                internedTabsIndentation[tabs] = tabString = repeatString("\t", tabs);
             }
             else {
                 tabString = internedTabsIndentation[tabs];
             }
 
-            return spaces ? tabString + repeat(" ", spaces) : tabString;
+            return spaces ? tabString + repeatString(" ", spaces) : tabString;
         }
         else {
             let spacesString: string;
@@ -1294,23 +1294,14 @@ namespace ts.formatting {
             }
 
             if (internedSpacesIndentation[quotient] === undefined) {
-                spacesString = repeat(" ", options.indentSize * quotient);
+                spacesString = repeatString(" ", options.indentSize * quotient);
                 internedSpacesIndentation[quotient] = spacesString;
             }
             else {
                 spacesString = internedSpacesIndentation[quotient];
             }
 
-            return remainder ? spacesString + repeat(" ", remainder) : spacesString;
-        }
-
-        function repeat(value: string, count: number): string {
-            let s = "";
-            for (let i = 0; i < count; i++) {
-                s += value;
-            }
-
-            return s;
+            return remainder ? spacesString + repeatString(" ", remainder) : spacesString;
         }
     }
 }
diff --git a/src/services/utilities.ts b/src/services/utilities.ts
index abfe5a7a55d..344a44a9f18 100644
--- a/src/services/utilities.ts
+++ b/src/services/utilities.ts
@@ -1110,6 +1110,14 @@ namespace ts {
     export function getSnapshotText(snap: IScriptSnapshot): string {
         return snap.getText(0, snap.getLength());
     }
+
+    export function repeatString(str: string, count: number): string {
+        let result = "";
+        for (let i = 0; i < count; i++) {
+            result += str;
+        }
+        return result;
+    }
 }
 
 // Display-part writer helpers