diff --git a/ts/tests/numberingTest.ts b/ts/tests/numberingTest.ts
index 932b58b5d1..fef296f69d 100644
--- a/ts/tests/numberingTest.ts
+++ b/ts/tests/numberingTest.ts
@@ -1,17 +1,16 @@
 import { expect } from "chai";
+import { Formatter } from "../export/formatter";
 import { Numbering } from "../numbering";
 import { AbstractNumbering } from "../numbering/abstract-numbering";
 import { Num } from "../numbering/num";
-import { Formatter } from '../export/formatter';
 
-function jsonify(obj: Object) {
-    let stringifiedJson = JSON.stringify(obj);
-    return JSON.parse(stringifiedJson);
+function jsonify(obj: object) {
+    return JSON.parse(JSON.stringify(obj));
 }
 
 describe("Numbering", () => {
 
-    let numbering = new Numbering;
+    let numbering: Numbering;
     beforeEach(() => {
         numbering = new Numbering();
     });
@@ -19,31 +18,31 @@ describe("Numbering", () => {
     describe("#constructor", () => {
         it("creates a default numbering with one abstract and one concrete instance", () => {
             const tree = new Formatter().format(numbering);
-            expect(Object.keys(tree)).to.deep.equal(['w:numbering']);
-            const abstractNums = tree['w:numbering'].filter(el => el['w:abstractNum']);
+            expect(Object.keys(tree)).to.deep.equal(["w:numbering"]);
+            const abstractNums = tree["w:numbering"].filter((el) => el["w:abstractNum"]);
             expect(abstractNums).to.have.lengthOf(1);
-            expect(abstractNums[0]['w:abstractNum']).to.deep.include.members([
+            expect(abstractNums[0]["w:abstractNum"]).to.deep.include.members([
                 {_attr: {"w:abstractNumId": 0, "w15:restartNumberingAfterBreak": 0}},
-                {"w:multiLevelType": [{"_attr": {"w:val": "hybridMultilevel"}}]},
+                {"w:multiLevelType": [{_attr: {"w:val": "hybridMultilevel"}}]},
             ]);
 
-            abstractNums.filter(el => el['w:lvl']).forEach((el, ix) => {
+            abstractNums.filter((el) => el["w:lvl"]).forEach((el, ix) => {
                 expect(Object.keys(el)).to.have.lengthOf(1);
-                expect(Object.keys(el['w:lvl']).sort()).to.deep.equal([
-                    "_attr", "w:start", "w:lvlJc", "w:numFmt", "w:pPr", "w:rPr"
-                ])
-                expect(el['w:lvl']).to.have.deep.members([
-                    {"_attr": {"w:ilvl": ix, "w15:tentative": 1}},
-                    {"w:start": [{"_attr": {"w:val": 1}}]},
-                    {"w:lvlJc": [{"_attr": {"w:val": "left"}}]},
-                    {"w:numFmt": [{"_attr": {"w:val": "bullet"}}]},
+                expect(Object.keys(el["w:lvl"]).sort()).to.deep.equal([
+                    "_attr", "w:start", "w:lvlJc", "w:numFmt", "w:pPr", "w:rPr",
+                ]);
+                expect(el["w:lvl"]).to.have.deep.members([
+                    {_attr: {"w:ilvl": ix, "w15:tentative": 1}},
+                    {"w:start": [{_attr: {"w:val": 1}}]},
+                    {"w:lvlJc": [{_attr: {"w:val": "left"}}]},
+                    {"w:numFmt": [{_attr: {"w:val": "bullet"}}]},
                 ]);
                 // Once chai 4.0.0 lands and #644 is resolved, we can add the following to the test:
                 // {"w:lvlText": [{"_attr": {"w:val": "•"}}]},
                 // {"w:rPr": [{"w:rFonts": [{"_attr": {"w:ascii": "Symbol", "w:hAnsi": "Symbol", "w:hint": "default"}}]}]},
                 // {"w:pPr": [{"_attr": {}},
                 //            {"w:ind": [{"_attr": {"w:left": 720, "w:hanging": 360}}]}]},
-            })
+            });
         });
     });
 
@@ -83,4 +82,4 @@ describe("AbstractNumbering", () => {
         const abstractNumbering = new AbstractNumbering(5);
         expect(abstractNumbering.id).to.equal(5);
     });
-});
\ No newline at end of file
+});