Iterable equality within object

CHANGELOG.md

@@ -19,6 +19,7 @@
 - `[jest-haste-map]` Fix the `mapper` option which was incorrectly ignored ([#8299](https://github.com/facebook/jest/pull/8299))
 - `[jest-jasmine2]` Fix describe return value warning being shown if the describe function throws ([#8335](https://github.com/facebook/jest/pull/8335))
 - `[jest-environment-jsdom]` Re-declare global prototype of JSDOMEnvironment ([#8352](https://github.com/facebook/jest/pull/8352))
+- `[expect]` Fix `iterableEquality` ignores other properties ([#8359](https://github.com/facebook/jest/pull/8359))
 
 ### Chore & Maintenance
 

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);
@@ -271,6 +284,49 @@ describe('iterableEquality', () => {
     ).toBe(false);
   });
 
+  test('returns true when given iterator within equal objects', () => {
+    const a = {
+      [Symbol.iterator]: () => ({next: () => ({done: true})}),
+      a: [],
+    };
+    const b = {
+      [Symbol.iterator]: () => ({next: () => ({done: true})}),
+      a: [],
+    };
+
+    expect(iterableEquality(a, b)).toBe(true);
+  });
+
+  test('returns false when given iterator within inequal objects', () => {
+    const a = {
+      [Symbol.iterator]: () => ({next: () => ({done: true})}),
+      a: [1],
+    };
+    const b = {
+      [Symbol.iterator]: () => ({next: () => ({done: true})}),
+      a: [],
+    };
+
+    expect(iterableEquality(a, b)).toBe(false);
+  });
+
+  test('returns false when given iterator within inequal nested objects', () => {
+    const a = {
+      [Symbol.iterator]: () => ({next: () => ({done: true})}),
+      a: {
+        b: [1],
+      },
+    };
+    const b = {
+      [Symbol.iterator]: () => ({next: () => ({done: true})}),
+      a: {
+        b: [],
+      },
+    };
+
+    expect(iterableEquality(a, b)).toBe(false);
+  });
+
   test('returns true when given circular Set shape', () => {
     const a1 = new Set();
     const a2 = new Set();

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) =>
@@ -251,6 +254,12 @@ export const iterableEquality = (
     return false;
   }
 
+  const aEntries = getObjectEntries(a);
+  const bEntries = getObjectEntries(b);
+  if (!equals(aEntries, bEntries)) {
+    return false;
+  }
+
   // Remove the first value from the stack of traversed values.
   aStack.pop();
   bStack.pop();