Iterable equality within object

packages/expect/src/__tests__/utils.test.js

@@ -12,6 +12,7 @@ const {stringify} = require('jest-matcher-utils');
 const {
   emptyObject,
   getObjectSubset,
+  getObjectEntries,
   getPath,
   hasOwnProperty,
   subsetEquality,
@@ -166,6 +167,18 @@ describe('getObjectSubset()', () => {
   });
 });
 
+describe('getObjectEntries', () => {
+  test('returns an empty array when called with null', () => {
+    expect(getObjectEntries(null)).toEqual([]);
+  });
+  test('returns an empty array when called with undefined', () => {
+    expect(getObjectEntries(undefined)).toEqual([]);
+  });
+  test('returns object entries', () => {
+    expect(getObjectEntries({ a: 1, b: 2 })).toEqual([['a', 1], ['b', 2]]);
+  });
+})
+
 describe('emptyObject()', () => {
   test('matches an empty object', () => {
     expect(emptyObject({})).toBe(true);

packages/expect/src/utils.ts

@@ -133,6 +133,9 @@ export const getObjectSubset = (object: any, subset: any): any => {
   return object;
 };
 
+export const getObjectEntries = (object: any): Array<any> =>
+  object == null ? [] : Object.keys(object).map((key) => [key, object[key]])
+
 const IteratorSymbol = Symbol.iterator;
 
 const hasIterator = (object: any) =>
@@ -251,8 +254,8 @@ export const iterableEquality = (
     return false;
   }
 
-  const aEntries = Object.entries(a);
-  const bEntries = Object.entries(b);
+  const aEntries = getObjectEntries(a);
+  const bEntries = getObjectEntries(b);
   if (!equals(aEntries, bEntries)) {
     return false;
   }