Jestify app/scripts/lib/**/*.test.js (#12890)

* Jestify app/scripts/lib/*.test.js

* Mocha config on mocha test script

* Add app/scripts/lib to include subdirs

.eslintrc.js

@@ -138,6 +138,7 @@ module.exports = {
         'development/**/*.test.js',
         'app/scripts/migrations/*.test.js',
         'app/scripts/platforms/*.test.js',
+        'app/scripts/lib/**/*.test.js',
       ],
       extends: ['@metamask/eslint-config-mocha'],
       rules: {
@@ -162,6 +163,7 @@ module.exports = {
         'development/**/*.test.js',
         'app/scripts/migrations/*.test.js',
         'app/scripts/platforms/*.test.js',
+        'app/scripts/lib/**/*.test.js',
       ],
       extends: ['@metamask/eslint-config-jest'],
       rules: {

.mocharc.js

@@ -1,7 +1,11 @@
 module.exports = {
   // TODO: Remove the `exit` setting, it can hide broken tests.
   exit: true,
-  ignore: ['./app/scripts/migrations/*.test.js', './app/scripts/platforms/*.test.js'],
+  ignore: [
+    './app/scripts/migrations/*.test.js',
+    './app/scripts/platforms/*.test.js',
+    './app/scripts/lib/**/*.test.js',
+  ],
   recursive: true,
   require: ['test/env.js', 'test/setup.js'],
 }

app/scripts/lib/ComposableObservableStore.test.js

@@ -1,4 +1,3 @@
-import { strict as assert } from 'assert';
 import { ObservableStore } from '@metamask/obs-store';
 import {
   BaseController,
@@ -48,17 +47,17 @@ class ExampleController extends BaseControllerV2 {
   }
 }
 
-describe('ComposableObservableStore', function () {
+describe('ComposableObservableStore', () => {
-  it('should register initial state', function () {
+  it('should register initial state', () => {
     const controllerMessenger = new ControllerMessenger();
     const store = new ComposableObservableStore({
       controllerMessenger,
       state: 'state',
     });
-    assert.strictEqual(store.getState(), 'state');
+    expect(store.getState()).toStrictEqual('state');
   });
 
-  it('should register initial structure', function () {
+  it('should register initial structure', () => {
     const controllerMessenger = new ControllerMessenger();
     const testStore = new ObservableStore();
     const store = new ComposableObservableStore({
@@ -66,28 +65,28 @@ describe('ComposableObservableStore', function () {
       controllerMessenger,
     });
     testStore.putState('state');
-    assert.deepEqual(store.getState(), { TestStore: 'state' });
+    expect(store.getState()).toStrictEqual({ TestStore: 'state' });
   });
 
-  it('should update structure with observable store', function () {
+  it('should update structure with observable store', () => {
     const controllerMessenger = new ControllerMessenger();
     const testStore = new ObservableStore();
     const store = new ComposableObservableStore({ controllerMessenger });
     store.updateStructure({ TestStore: testStore });
     testStore.putState('state');
-    assert.deepEqual(store.getState(), { TestStore: 'state' });
+    expect(store.getState()).toStrictEqual({ TestStore: 'state' });
   });
 
-  it('should update structure with BaseController-based controller', function () {
+  it('should update structure with BaseController-based controller', () => {
     const controllerMessenger = new ControllerMessenger();
     const oldExampleController = new OldExampleController();
     const store = new ComposableObservableStore({ controllerMessenger });
     store.updateStructure({ OldExample: oldExampleController });
     oldExampleController.updateBaz('state');
-    assert.deepEqual(store.getState(), { OldExample: { baz: 'state' } });
+    expect(store.getState()).toStrictEqual({ OldExample: { baz: 'state' } });
   });
 
-  it('should update structure with BaseControllerV2-based controller', function () {
+  it('should update structure with BaseControllerV2-based controller', () => {
     const controllerMessenger = new ControllerMessenger();
     const exampleController = new ExampleController({
       messenger: controllerMessenger,
@@ -95,11 +94,10 @@ describe('ComposableObservableStore', function () {
     const store = new ComposableObservableStore({ controllerMessenger });
     store.updateStructure({ Example: exampleController });
     exampleController.updateBar('state');
-    console.log(exampleController.state);
+    expect(store.getState()).toStrictEqual({ Example: { bar: 'state' } });
-    assert.deepEqual(store.getState(), { Example: { bar: 'state' } });
   });
 
-  it('should update structure with all three types of stores', function () {
+  it('should update structure with all three types of stores', () => {
     const controllerMessenger = new ControllerMessenger();
     const exampleStore = new ObservableStore();
     const exampleController = new ExampleController({
@@ -115,14 +113,14 @@ describe('ComposableObservableStore', function () {
     exampleStore.putState('state');
     exampleController.updateBar('state');
     oldExampleController.updateBaz('state');
-    assert.deepEqual(store.getState(), {
+    expect(store.getState()).toStrictEqual({
       Example: { bar: 'state' },
       OldExample: { baz: 'state' },
       Store: 'state',
     });
   });
 
-  it('should return flattened state', function () {
+  it('should return flattened state', () => {
     const controllerMessenger = new ControllerMessenger();
     const fooStore = new ObservableStore({ foo: 'foo' });
     const barController = new ExampleController({
@@ -142,46 +140,48 @@ describe('ComposableObservableStore', function () {
         BazStore: bazController.state,
       },
     });
-    assert.deepEqual(store.getFlatState(), {
+    expect(store.getFlatState()).toStrictEqual({
       foo: 'foo',
       bar: 'bar',
       baz: 'baz',
     });
   });
 
-  it('should return empty flattened state when not configured', function () {
+  it('should return empty flattened state when not configured', () => {
     const controllerMessenger = new ControllerMessenger();
     const store = new ComposableObservableStore({ controllerMessenger });
-    assert.deepEqual(store.getFlatState(), {});
+    expect(store.getFlatState()).toStrictEqual({});
   });
 
-  it('should throw if the controller messenger is omitted and the config includes a BaseControllerV2 controller', function () {
+  it('should throw if the controller messenger is omitted and the config includes a BaseControllerV2 controller', () => {
     const controllerMessenger = new ControllerMessenger();
     const exampleController = new ExampleController({
       messenger: controllerMessenger,
     });
-    assert.throws(
+    expect(
       () =>
         new ComposableObservableStore({
           config: {
             Example: exampleController,
           },
         }),
-    );
+    ).toThrow(`Cannot read property 'subscribe' of undefined`);
   });
 
-  it('should throw if the controller messenger is omitted and updateStructure called with a BaseControllerV2 controller', function () {
+  it('should throw if the controller messenger is omitted and updateStructure called with a BaseControllerV2 controller', () => {
     const controllerMessenger = new ControllerMessenger();
     const exampleController = new ExampleController({
       messenger: controllerMessenger,
     });
     const store = new ComposableObservableStore({});
-    assert.throws(() => store.updateStructure({ Example: exampleController }));
+    expect(() => store.updateStructure({ Example: exampleController })).toThrow(
+      `Cannot read property 'subscribe' of undefined`,
+    );
   });
 
-  it('should throw if initialized with undefined config entry', function () {
+  it('should throw if initialized with undefined config entry', () => {
     const controllerMessenger = new ControllerMessenger();
-    assert.throws(
+    expect(
       () =>
         new ComposableObservableStore({
           config: {
@@ -189,6 +189,6 @@ describe('ComposableObservableStore', function () {
           },
           controllerMessenger,
         }),
-    );
+    ).toThrow(`Undefined 'Example'`);
   });
 });

app/scripts/lib/buy-eth-url.test.js

@@ -1,4 +1,3 @@
-import { strict as assert } from 'assert';
 import nock from 'nock';
 import {
   KOVAN_CHAIN_ID,
@@ -27,8 +26,8 @@ const KOVAN = {
   chainId: KOVAN_CHAIN_ID,
 };
 
-describe('buy-eth-url', function () {
+describe('buy-eth-url', () => {
-  it('returns Wyre url with an ETH address for Ethereum mainnet', async function () {
+  it('returns Wyre url with an ETH address for Ethereum mainnet', async () => {
     nock(SWAPS_API_V2_BASE_URL)
       .get(
         `/networks/1/fiatOnRampUrl?serviceName=wyre&destinationAddress=${ETH_ADDRESS}`,
@@ -37,43 +36,40 @@ describe('buy-eth-url', function () {
         url: `https://pay.sendwyre.com/purchase?accountId=${WYRE_ACCOUNT_ID}&utm_campaign=${WYRE_ACCOUNT_ID}&destCurrency=ETH&utm_medium=widget&paymentMethod=debit-card&reservation=MLZVUF8FMXZUMARJC23B&dest=ethereum%3A${ETH_ADDRESS}&utm_source=checkout`,
       });
     const wyreUrl = await getBuyEthUrl(MAINNET);
-    assert.equal(
+    expect(wyreUrl).toStrictEqual(
-      wyreUrl,
       `https://pay.sendwyre.com/purchase?accountId=${WYRE_ACCOUNT_ID}&utm_campaign=${WYRE_ACCOUNT_ID}&destCurrency=ETH&utm_medium=widget&paymentMethod=debit-card&reservation=MLZVUF8FMXZUMARJC23B&dest=ethereum%3A${ETH_ADDRESS}&utm_source=checkout`,
     );
     nock.cleanAll();
   });
 
-  it('returns a fallback Wyre url if /orders/reserve API call fails', async function () {
+  it('returns a fallback Wyre url if /orders/reserve API call fails', async () => {
     const wyreUrl = await getBuyEthUrl(MAINNET);
 
-    assert.equal(
+    expect(wyreUrl).toStrictEqual(
-      wyreUrl,
       `https://pay.sendwyre.com/purchase?dest=ethereum:${ETH_ADDRESS}&destCurrency=ETH&accountId=${WYRE_ACCOUNT_ID}&paymentMethod=debit-card`,
     );
   });
 
-  it('returns Transak url with an ETH address for Ethereum mainnet', async function () {
+  it('returns Transak url with an ETH address for Ethereum mainnet', async () => {
     const transakUrl = await getBuyEthUrl({ ...MAINNET, service: 'transak' });
 
-    assert.equal(
+    expect(transakUrl).toStrictEqual(
-      transakUrl,
       `https://global.transak.com/?apiKey=${TRANSAK_API_KEY}&hostURL=https%3A%2F%2Fmetamask.io&defaultCryptoCurrency=ETH&walletAddress=${ETH_ADDRESS}`,
     );
   });
 
-  it('returns metamask ropsten faucet for network 3', async function () {
+  it('returns metamask ropsten faucet for network 3', async () => {
     const ropstenUrl = await getBuyEthUrl(ROPSTEN);
-    assert.equal(ropstenUrl, 'https://faucet.metamask.io/');
+    expect(ropstenUrl).toStrictEqual('https://faucet.metamask.io/');
   });
 
-  it('returns rinkeby dapp for network 4', async function () {
+  it('returns rinkeby dapp for network 4', async () => {
     const rinkebyUrl = await getBuyEthUrl(RINKEBY);
-    assert.equal(rinkebyUrl, 'https://www.rinkeby.io/');
+    expect(rinkebyUrl).toStrictEqual('https://www.rinkeby.io/');
   });
 
-  it('returns kovan github test faucet for network 42', async function () {
+  it('returns kovan github test faucet for network 42', async () => {
     const kovanUrl = await getBuyEthUrl(KOVAN);
-    assert.equal(kovanUrl, 'https://github.com/kovan-testnet/faucet');
+    expect(kovanUrl).toStrictEqual('https://github.com/kovan-testnet/faucet');
   });
 });

app/scripts/lib/cleanErrorStack.test.js

@@ -1,34 +1,36 @@
-import { strict as assert } from 'assert';
 import cleanErrorStack from './cleanErrorStack';
 
-describe('Clean Error Stack', function () {
+describe('Clean Error Stack', () => {
   const testMessage = 'Test Message';
   const testError = new Error(testMessage);
   const undefinedErrorName = new Error(testMessage);
   const blankErrorName = new Error(testMessage);
   const blankMsgError = new Error();
 
-  beforeEach(function () {
+  beforeEach(() => {
     undefinedErrorName.name = undefined;
     blankErrorName.name = '';
   });
 
-  it('tests error with message', function () {
+  it('tests error with message', () => {
-    assert.equal(cleanErrorStack(testError).toString(), 'Error: Test Message');
+    expect(cleanErrorStack(testError).toString()).toStrictEqual(
-  });
-
-  it('tests error with undefined name', function () {
-    assert.equal(
-      cleanErrorStack(undefinedErrorName).toString(),
       'Error: Test Message',
     );
   });
 
-  it('tests error with blank name', function () {
+  it('tests error with undefined name', () => {
-    assert.equal(cleanErrorStack(blankErrorName).toString(), 'Test Message');
+    expect(cleanErrorStack(undefinedErrorName).toString()).toStrictEqual(
+      'Error: Test Message',
+    );
   });
 
-  it('tests error with blank message', function () {
+  it('tests error with blank name', () => {
-    assert.equal(cleanErrorStack(blankMsgError).toString(), 'Error');
+    expect(cleanErrorStack(blankErrorName).toString()).toStrictEqual(
+      'Test Message',
+    );
+  });
+
+  it('tests error with blank message', () => {
+    expect(cleanErrorStack(blankMsgError).toString()).toStrictEqual('Error');
   });
 });

app/scripts/lib/createMetaRPCHandler.test.js

@@ -1,13 +1,11 @@
-import { strict as assert } from 'assert';
 import { obj as createThoughStream } from 'through2';
 import createMetaRPCHandler from './createMetaRPCHandler';
 
-describe('createMetaRPCHandler', function () {
+describe('createMetaRPCHandler', () => {
-  it('can call the api when handler receives a JSON-RPC request', function (done) {
+  it('can call the api when handler receives a JSON-RPC request', () => {
     const api = {
       foo: (param1) => {
-        assert.strictEqual(param1, 'bar');
+        expect(param1).toStrictEqual('bar');
-        done();
       },
     };
     const streamTest = createThoughStream();
@@ -18,10 +16,10 @@ describe('createMetaRPCHandler', function () {
       params: ['bar'],
     });
   });
-  it('can write the response to the outstream when api callback is called', function (done) {
+  it('can write the response to the outstream when api callback is called', () => {
     const api = {
       foo: (param1, cb) => {
-        assert.strictEqual(param1, 'bar');
+        expect(param1).toStrictEqual('bar');
         cb(null, 'foobarbaz');
       },
     };
@@ -33,15 +31,14 @@ describe('createMetaRPCHandler', function () {
       params: ['bar'],
     });
     streamTest.on('data', (data) => {
-      assert.strictEqual(data.result, 'foobarbaz');
+      expect(data.result).toStrictEqual('foobarbaz');
       streamTest.end();
-      done();
     });
   });
-  it('can write the error to the outstream when api callback is called with an error', function (done) {
+  it('can write the error to the outstream when api callback is called with an error', () => {
     const api = {
       foo: (param1, cb) => {
-        assert.strictEqual(param1, 'bar');
+        expect(param1).toStrictEqual('bar');
         cb(new Error('foo-error'));
       },
     };
@@ -53,32 +50,32 @@ describe('createMetaRPCHandler', function () {
       params: ['bar'],
     });
     streamTest.on('data', (data) => {
-      assert.strictEqual(data.error.message, 'foo-error');
+      expect(data.error.message).toStrictEqual('foo-error');
       streamTest.end();
-      done();
     });
   });
-  it('can not throw an error for writing an error after end', function (done) {
+  it('can not throw an error for writing an error after end', () => {
     const api = {
       foo: (param1, cb) => {
-        assert.strictEqual(param1, 'bar');
+        expect(param1).toStrictEqual('bar');
         cb(new Error('foo-error'));
       },
     };
     const streamTest = createThoughStream();
     const handler = createMetaRPCHandler(api, streamTest);
     streamTest.end();
-    handler({
+    expect(() => {
-      id: 1,
+      handler({
-      method: 'foo',
+        id: 1,
-      params: ['bar'],
+        method: 'foo',
-    });
+        params: ['bar'],
-    done();
+      });
+    }).not.toThrow();
   });
-  it('can not throw an error for write after end', function (done) {
+  it('can not throw an error for write after end', () => {
     const api = {
       foo: (param1, cb) => {
-        assert.strictEqual(param1, 'bar');
+        expect(param1).toStrictEqual('bar');
         cb(undefined, {
           foo: 'bar',
         });
@@ -87,11 +84,12 @@ describe('createMetaRPCHandler', function () {
     const streamTest = createThoughStream();
     const handler = createMetaRPCHandler(api, streamTest);
     streamTest.end();
-    handler({
+    expect(() => {
-      id: 1,
+      handler({
-      method: 'foo',
+        id: 1,
-      params: ['bar'],
+        method: 'foo',
-    });
+        params: ['bar'],
-    done();
+      });
+    }).not.toThrow();
   });
 });

app/scripts/lib/message-manager.test.js

@@ -1,27 +1,25 @@
-import { strict as assert } from 'assert';
-import sinon from 'sinon';
 import { TRANSACTION_STATUSES } from '../../../shared/constants/transaction';
 import MessageManager from './message-manager';
 
-describe('Message Manager', function () {
+describe('Message Manager', () => {
   let messageManager;
 
-  beforeEach(function () {
+  beforeEach(() => {
     messageManager = new MessageManager({
-      metricsEvent: sinon.fake(),
+      metricsEvent: jest.fn(),
     });
   });
 
-  describe('#getMsgList', function () {
+  describe('#getMsgList', () => {
-    it('when new should return empty array', function () {
+    it('when new should return empty array', () => {
       const result = messageManager.messages;
-      assert.ok(Array.isArray(result));
+      expect(Array.isArray(result)).toStrictEqual(true);
-      assert.equal(result.length, 0);
+      expect(result).toHaveLength(0);
     });
   });
 
-  describe('#addMsg', function () {
+  describe('#addMsg', () => {
-    it('adds a Msg returned in getMsgList', function () {
+    it('adds a Msg returned in getMsgList', () => {
       const Msg = {
         id: 1,
         status: TRANSACTION_STATUSES.APPROVED,
@@ -29,14 +27,14 @@ describe('Message Manager', function () {
       };
       messageManager.addMsg(Msg);
       const result = messageManager.messages;
-      assert.ok(Array.isArray(result));
+      expect(Array.isArray(result)).toStrictEqual(true);
-      assert.equal(result.length, 1);
+      expect(result).toHaveLength(1);
-      assert.equal(result[0].id, 1);
+      expect(result[0].id).toStrictEqual(1);
     });
   });
 
-  describe('#setMsgStatusApproved', function () {
+  describe('#setMsgStatusApproved', () => {
-    it('sets the Msg status to approved', function () {
+    it('sets the Msg status to approved', () => {
       const Msg = {
         id: 1,
         status: 'unapproved',
@@ -45,14 +43,14 @@ describe('Message Manager', function () {
       messageManager.addMsg(Msg);
       messageManager.setMsgStatusApproved(1);
       const result = messageManager.messages;
-      assert.ok(Array.isArray(result));
+      expect(Array.isArray(result)).toStrictEqual(true);
-      assert.equal(result.length, 1);
+      expect(result).toHaveLength(1);
-      assert.equal(result[0].status, TRANSACTION_STATUSES.APPROVED);
+      expect(result[0].status).toStrictEqual(TRANSACTION_STATUSES.APPROVED);
     });
   });
 
-  describe('#rejectMsg', function () {
+  describe('#rejectMsg', () => {
-    it('sets the Msg status to rejected', function () {
+    it('sets the Msg status to rejected', () => {
       const Msg = {
         id: 1,
         status: 'unapproved',
@@ -61,14 +59,14 @@ describe('Message Manager', function () {
       messageManager.addMsg(Msg);
       messageManager.rejectMsg(1);
       const result = messageManager.messages;
-      assert.ok(Array.isArray(result));
+      expect(Array.isArray(result)).toStrictEqual(true);
-      assert.equal(result.length, 1);
+      expect(result).toHaveLength(1);
-      assert.equal(result[0].status, TRANSACTION_STATUSES.REJECTED);
+      expect(result[0].status).toStrictEqual(TRANSACTION_STATUSES.REJECTED);
     });
   });
 
-  describe('#_updateMsg', function () {
+  describe('#_updateMsg', () => {
-    it('replaces the Msg with the same id', function () {
+    it('replaces the Msg with the same id', () => {
       messageManager.addMsg({
         id: '1',
         status: 'unapproved',
@@ -86,12 +84,12 @@ describe('Message Manager', function () {
         metamaskNetworkId: 'unit test',
       });
       const result = messageManager.getMsg('1');
-      assert.equal(result.hash, 'foo');
+      expect(result.hash).toStrictEqual('foo');
     });
   });
 
-  describe('#getUnapprovedMsgs', function () {
+  describe('#getUnapprovedMsgs', () => {
-    it('returns unapproved Msgs in a hash', function () {
+    it('returns unapproved Msgs in a hash', () => {
       messageManager.addMsg({
         id: '1',
         status: 'unapproved',
@@ -103,14 +101,14 @@ describe('Message Manager', function () {
         metamaskNetworkId: 'unit test',
       });
       const result = messageManager.getUnapprovedMsgs();
-      assert.equal(typeof result, 'object');
+      expect(typeof result).toStrictEqual('object');
-      assert.equal(result['1'].status, 'unapproved');
+      expect(result['1'].status).toStrictEqual('unapproved');
-      assert.equal(result['2'], undefined);
+      expect(result['2']).toBeUndefined();
     });
   });
 
-  describe('#getMsg', function () {
+  describe('#getMsg', () => {
-    it('returns a Msg with the requested id', function () {
+    it('returns a Msg with the requested id', () => {
       messageManager.addMsg({
         id: '1',
         status: 'unapproved',
@@ -121,9 +119,8 @@ describe('Message Manager', function () {
         status: TRANSACTION_STATUSES.APPROVED,
         metamaskNetworkId: 'unit test',
       });
-      assert.equal(messageManager.getMsg('1').status, 'unapproved');
+      expect(messageManager.getMsg('1').status).toStrictEqual('unapproved');
-      assert.equal(
+      expect(messageManager.getMsg('2').status).toStrictEqual(
-        messageManager.getMsg('2').status,
         TRANSACTION_STATUSES.APPROVED,
       );
     });

app/scripts/lib/metaRPCClientFactory.test.js

@@ -1,24 +1,21 @@
-import { strict as assert } from 'assert';
 import { obj as createThoughStream } from 'through2';
 import metaRPCClientFactory from './metaRPCClientFactory';
 
-describe('metaRPCClientFactory', function () {
+describe('metaRPCClientFactory', () => {
-  it('should be able to make an rpc request with the method', function (done) {
+  it('should be able to make an rpc request with the method', () => {
     const streamTest = createThoughStream((chunk) => {
-      assert.strictEqual(chunk.method, 'foo');
+      expect(chunk.method).toStrictEqual('foo');
-      done();
     });
     const metaRPCClient = metaRPCClientFactory(streamTest);
     metaRPCClient.foo();
   });
-  it('should be able to make an rpc request/response with the method and params and node-style callback', function (done) {
+  it('should be able to make an rpc request/response with the method and params and node-style callback', () => {
     const streamTest = createThoughStream();
     const metaRPCClient = metaRPCClientFactory(streamTest);
 
     // make a "foo" method call
     metaRPCClient.foo('bar', (_, result) => {
-      assert.strictEqual(result, 'foobarbaz');
+      expect(result).toStrictEqual('foobarbaz');
-      done();
     });
 
     // fake a response
@@ -30,15 +27,14 @@ describe('metaRPCClientFactory', function () {
       });
     });
   });
-  it('should be able to make an rpc request/error with the method and params and node-style callback', function (done) {
+  it('should be able to make an rpc request/error with the method and params and node-style callback', () => {
     const streamTest = createThoughStream();
     const metaRPCClient = metaRPCClientFactory(streamTest);
 
     // make a "foo" method call
     metaRPCClient.foo('bar', (err) => {
-      assert.strictEqual(err.message, 'foo-message');
+      expect(err.message).toStrictEqual('foo-message');
-      assert.strictEqual(err.code, 1);
+      expect(err.code).toStrictEqual(1);
-      done();
     });
 
     metaRPCClient.requests.forEach((_, key) => {
@@ -53,17 +49,16 @@ describe('metaRPCClientFactory', function () {
     });
   });
 
-  it('should be able to make an rpc request/response with the method and params and node-style callback with multiple instances of metaRPCClientFactory and the same connectionStream', function (done) {
+  it('should be able to make an rpc request/response with the method and params and node-style callback with multiple instances of metaRPCClientFactory and the same connectionStream', () => {
     const streamTest = createThoughStream();
     const metaRPCClient = metaRPCClientFactory(streamTest);
     const metaRPCClient2 = metaRPCClientFactory(streamTest);
 
     // make a "foo" method call, followed by "baz" call on metaRPCClient2
     metaRPCClient.foo('bar', (_, result) => {
-      assert.strictEqual(result, 'foobarbaz');
+      expect(result).toStrictEqual('foobarbaz');
       metaRPCClient2.baz('bar', (err) => {
-        assert.strictEqual(err, null);
+        expect(err).toBeNull();
-        done();
       });
     });
 
@@ -86,13 +81,12 @@ describe('metaRPCClientFactory', function () {
     });
   });
 
-  it('should be able to handle notifications', function (done) {
+  it('should be able to handle notifications', () => {
     const streamTest = createThoughStream();
     const metaRPCClient = metaRPCClientFactory(streamTest);
 
     metaRPCClient.onNotification((notification) => {
-      assert(notification.method, 'foobarbaz');
+      expect(notification.method).toStrictEqual('foobarbaz');
-      done();
     });
 
     // send a notification
@@ -103,13 +97,12 @@ describe('metaRPCClientFactory', function () {
     });
   });
 
-  it('should be able to handle errors with no id', function (done) {
+  it('should be able to handle errors with no id', () => {
     const streamTest = createThoughStream();
     const metaRPCClient = metaRPCClientFactory(streamTest);
 
     metaRPCClient.onUncaughtError((error) => {
-      assert(error.code, 1);
+      expect(error.code).toStrictEqual(1);
-      done();
     });
 
     streamTest.write({
@@ -121,13 +114,12 @@ describe('metaRPCClientFactory', function () {
     });
   });
 
-  it('should be able to handle errors with null id', function (done) {
+  it('should be able to handle errors with null id', () => {
     const streamTest = createThoughStream();
     const metaRPCClient = metaRPCClientFactory(streamTest);
 
     metaRPCClient.onUncaughtError((error) => {
-      assert(error.code, 1);
+      expect(error.code).toStrictEqual(1);
-      done();
     });
 
     streamTest.write({

app/scripts/lib/migrator/index.test.js

@@ -1,5 +1,5 @@
+/* eslint-disable jest/no-conditional-expect */
 import fs from 'fs';
-import { strict as assert } from 'assert';
 import { cloneDeep } from 'lodash';
 import liveMigrations from '../../migrations';
 import data from '../../first-time-state';
@@ -39,11 +39,11 @@ const firstTimeState = {
   data,
 };
 
-describe('migrations', function () {
+describe('migrations', () => {
-  describe('liveMigrations require list', function () {
+  describe('liveMigrations require list', () => {
     let migrationNumbers;
 
-    before(function () {
+    beforeAll(() => {
       const fileNames = fs.readdirSync('./app/scripts/migrations/');
       migrationNumbers = fileNames
         .reduce((acc, filename) => {
@@ -56,21 +56,19 @@ describe('migrations', function () {
         .map((num) => parseInt(num, 10));
     });
 
-    it('should include all migrations', function () {
+    it('should include all migrations', () => {
       migrationNumbers.forEach((num) => {
         const migration = liveMigrations.find((m) => m.version === num);
-        assert(
+        expect(migration.version).toStrictEqual(num);
-          migration,
-          `migration not included in 'migrations/index.js': ${num}`,
-        );
       });
     });
 
-    it('should have tests for all migrations', function () {
+    it('should have tests for all migrations', () => {
       const fileNames = fs.readdirSync('./app/scripts/migrations/');
       const testNumbers = fileNames
         .reduce((acc, filename) => {
           const name = filename.split('.test.')[0];
+          // eslint-disable-next-line jest/no-if
           if (/^\d+$/u.test(name)) {
             acc.push(name);
           }
@@ -80,30 +78,31 @@ describe('migrations', function () {
 
       migrationNumbers.forEach((num) => {
         if (num >= 33) {
-          assert.ok(
+          expect(testNumbers).toContain(num);
-            testNumbers.includes(num),
-            `no test found for migration: ${num}`,
-          );
         }
       });
     });
   });
 
-  describe('Migrator', function () {
+  describe('Migrator', () => {
-    it('migratedData version should be version 3', async function () {
+    it('migratedData version should be version 3', async () => {
       const migrator = new Migrator({ migrations: stubMigrations });
       const migratedData = await migrator.migrateData(versionedData);
-      assert.equal(migratedData.meta.version, stubMigrations[2].version);
+      expect(migratedData.meta.version).toStrictEqual(
+        stubMigrations[2].version,
+      );
     });
 
-    it('should match the last version in live migrations', async function () {
+    it('should match the last version in live migrations', async () => {
       const migrator = new Migrator({ migrations: liveMigrations });
       const migratedData = await migrator.migrateData(firstTimeState);
       const last = liveMigrations.length - 1;
-      assert.equal(migratedData.meta.version, liveMigrations[last].version);
+      expect(migratedData.meta.version).toStrictEqual(
+        liveMigrations[last].version,
+      );
     });
 
-    it('should emit an error', async function () {
+    it('should emit an error', async () => {
       const migrator = new Migrator({
         migrations: [
           {
@@ -114,7 +113,9 @@ describe('migrations', function () {
           },
         ],
       });
-      await assert.rejects(migrator.migrateData({ meta: { version: 0 } }));
+      await expect(async () => {
+        await migrator.migrateData({ meta: { version: 0 } });
+      }).rejects.toThrow('Error: MetaMask Migration Error #1: test');
     });
   });
 });

app/scripts/lib/nodeify.test.js

@@ -1,7 +1,6 @@
-import { strict as assert } from 'assert';
 import nodeify from './nodeify';
 
-describe('nodeify', function () {
+describe('nodeify', () => {
   const obj = {
     foo: 'bar',
     promiseFunc(a) {
@@ -10,65 +9,33 @@ describe('nodeify', function () {
     },
   };
 
-  it('should retain original context', function (done) {
+  it('should retain original context', () => {
     const nodified = nodeify(obj.promiseFunc, obj);
-    nodified('baz', (err, res) => {
+    nodified('baz', (_, res) => {
-      if (!err) {
+      expect(res).toStrictEqual('barbaz');
-        assert.equal(res, 'barbaz');
-        done();
-        return;
-      }
-
-      done(new Error(err.toString()));
     });
   });
 
-  it('no callback - should allow the last argument to not be a function', function (done) {
+  it('no callback - should allow the last argument to not be a function', async () => {
     const nodified = nodeify(obj.promiseFunc, obj);
-    try {
+    await expect(() => {
       nodified('baz');
-      done();
+    }).not.toThrow();
-    } catch (err) {
-      done(
-        new Error(
-          'should not have thrown if the last argument is not a function',
-        ),
-      );
-    }
   });
 
-  it('sync functions - returns value', function (done) {
+  it('sync functions - returns value', async () => {
     const nodified = nodeify(() => 42);
-    try {
+    nodified((_, result) => {
-      nodified((err, result) => {
+      expect(42).toStrictEqual(result);
-        if (err) {
+    });
-          done(new Error(`should not have thrown any error: ${err.message}`));
-          return;
-        }
-        assert.equal(42, result, 'got expected result');
-      });
-      done();
-    } catch (err) {
-      done(new Error(`should not have thrown any error: ${err.message}`));
-    }
   });
 
-  it('sync functions - handles errors', function (done) {
+  it('sync functions - handles errors', () => {
     const nodified = nodeify(() => {
       throw new Error('boom!');
     });
-    try {
+    nodified((err, _) => {
-      nodified((err, result) => {
+      expect(err.message).toStrictEqual('boom!');
-        if (result) {
+    });
-          done(new Error('should not have returned any result'));
-          return;
-        }
-        assert.ok(err, 'got expected error');
-        assert.ok(err.message.includes('boom!'), 'got expected error message');
-      });
-      done();
-    } catch (err) {
-      done(new Error(`should not have thrown any error: ${err.message}`));
-    }
   });
 });

app/scripts/lib/personal-message-manager.test.js

@@ -1,25 +1,25 @@
-import { strict as assert } from 'assert';
-import sinon from 'sinon';
 import { TRANSACTION_STATUSES } from '../../../shared/constants/transaction';
 import PersonalMessageManager from './personal-message-manager';
 
-describe('Personal Message Manager', function () {
+describe('Personal Message Manager', () => {
   let messageManager;
 
-  beforeEach(function () {
+  beforeEach(() => {
-    messageManager = new PersonalMessageManager({ metricsEvent: sinon.fake() });
+    messageManager = new PersonalMessageManager({
-  });
+      metricsEvent: jest.fn(),
-
-  describe('#getMsgList', function () {
-    it('when new should return empty array', function () {
-      const result = messageManager.messages;
-      assert.ok(Array.isArray(result));
-      assert.equal(result.length, 0);
     });
   });
 
-  describe('#addMsg', function () {
+  describe('#getMsgList', () => {
-    it('adds a Msg returned in getMsgList', function () {
+    it('when new should return empty array', () => {
+      const result = messageManager.messages;
+      expect(Array.isArray(result)).toStrictEqual(true);
+      expect(result).toHaveLength(0);
+    });
+  });
+
+  describe('#addMsg', () => {
+    it('adds a Msg returned in getMsgList', () => {
       const Msg = {
         id: 1,
         status: TRANSACTION_STATUSES.APPROVED,
@@ -27,14 +27,14 @@ describe('Personal Message Manager', function () {
       };
       messageManager.addMsg(Msg);
       const result = messageManager.messages;
-      assert.ok(Array.isArray(result));
+      expect(Array.isArray(result)).toStrictEqual(true);
-      assert.equal(result.length, 1);
+      expect(result).toHaveLength(1);
-      assert.equal(result[0].id, 1);
+      expect(result[0].id).toStrictEqual(1);
     });
   });
 
-  describe('#setMsgStatusApproved', function () {
+  describe('#setMsgStatusApproved', () => {
-    it('sets the Msg status to approved', function () {
+    it('sets the Msg status to approved', () => {
       const Msg = {
         id: 1,
         status: TRANSACTION_STATUSES.UNAPPROVED,
@@ -43,14 +43,14 @@ describe('Personal Message Manager', function () {
       messageManager.addMsg(Msg);
       messageManager.setMsgStatusApproved(1);
       const result = messageManager.messages;
-      assert.ok(Array.isArray(result));
+      expect(Array.isArray(result)).toStrictEqual(true);
-      assert.equal(result.length, 1);
+      expect(result).toHaveLength(1);
-      assert.equal(result[0].status, TRANSACTION_STATUSES.APPROVED);
+      expect(result[0].status).toStrictEqual(TRANSACTION_STATUSES.APPROVED);
     });
   });
 
-  describe('#rejectMsg', function () {
+  describe('#rejectMsg', () => {
-    it('sets the Msg status to rejected', function () {
+    it('sets the Msg status to rejected', () => {
       const Msg = {
         id: 1,
         status: TRANSACTION_STATUSES.UNAPPROVED,
@@ -59,14 +59,14 @@ describe('Personal Message Manager', function () {
       messageManager.addMsg(Msg);
       messageManager.rejectMsg(1);
       const result = messageManager.messages;
-      assert.ok(Array.isArray(result));
+      expect(Array.isArray(result)).toStrictEqual(true);
-      assert.equal(result.length, 1);
+      expect(result).toHaveLength(1);
-      assert.equal(result[0].status, TRANSACTION_STATUSES.REJECTED);
+      expect(result[0].status).toStrictEqual(TRANSACTION_STATUSES.REJECTED);
     });
   });
 
-  describe('#_updateMsg', function () {
+  describe('#_updateMsg', () => {
-    it('replaces the Msg with the same id', function () {
+    it('replaces the Msg with the same id', () => {
       messageManager.addMsg({
         id: '1',
         status: TRANSACTION_STATUSES.UNAPPROVED,
@@ -84,12 +84,12 @@ describe('Personal Message Manager', function () {
         metamaskNetworkId: 'unit test',
       });
       const result = messageManager.getMsg('1');
-      assert.equal(result.hash, 'foo');
+      expect(result.hash).toStrictEqual('foo');
     });
   });
 
-  describe('#getUnapprovedMsgs', function () {
+  describe('#getUnapprovedMsgs', () => {
-    it('returns unapproved Msgs in a hash', function () {
+    it('returns unapproved Msgs in a hash', () => {
       messageManager.addMsg({
         id: '1',
         status: TRANSACTION_STATUSES.UNAPPROVED,
@@ -101,14 +101,14 @@ describe('Personal Message Manager', function () {
         metamaskNetworkId: 'unit test',
       });
       const result = messageManager.getUnapprovedMsgs();
-      assert.equal(typeof result, 'object');
+      expect(typeof result).toStrictEqual('object');
-      assert.equal(result['1'].status, TRANSACTION_STATUSES.UNAPPROVED);
+      expect(result['1'].status).toStrictEqual(TRANSACTION_STATUSES.UNAPPROVED);
-      assert.equal(result['2'], undefined);
+      expect(result['2']).toBeUndefined();
     });
   });
 
-  describe('#getMsg', function () {
+  describe('#getMsg', () => {
-    it('returns a Msg with the requested id', function () {
+    it('returns a Msg with the requested id', () => {
       messageManager.addMsg({
         id: '1',
         status: TRANSACTION_STATUSES.UNAPPROVED,
@@ -119,34 +119,32 @@ describe('Personal Message Manager', function () {
         status: TRANSACTION_STATUSES.APPROVED,
         metamaskNetworkId: 'unit test',
       });
-      assert.equal(
+      expect(messageManager.getMsg('1').status).toStrictEqual(
-        messageManager.getMsg('1').status,
         TRANSACTION_STATUSES.UNAPPROVED,
       );
-      assert.equal(
+      expect(messageManager.getMsg('2').status).toStrictEqual(
-        messageManager.getMsg('2').status,
         TRANSACTION_STATUSES.APPROVED,
       );
     });
   });
 
-  describe('#normalizeMsgData', function () {
+  describe('#normalizeMsgData', () => {
-    it('converts text to a utf8 hex string', function () {
+    it('converts text to a utf8 hex string', () => {
       const input = 'hello';
       const output = messageManager.normalizeMsgData(input);
-      assert.equal(output, '0x68656c6c6f', 'predictably hex encoded');
+      expect(output).toStrictEqual('0x68656c6c6f');
     });
 
-    it('tolerates a hex prefix', function () {
+    it('tolerates a hex prefix', () => {
       const input = '0x12';
       const output = messageManager.normalizeMsgData(input);
-      assert.equal(output, '0x12', 'un modified');
+      expect(output).toStrictEqual('0x12');
     });
 
-    it('tolerates normal hex', function () {
+    it('tolerates normal hex', () => {
       const input = '12';
       const output = messageManager.normalizeMsgData(input);
-      assert.equal(output, '0x12', 'adds prefix');
+      expect(output).toStrictEqual('0x12');
     });
   });
 });

app/scripts/lib/seed-phrase-verifier.test.js

@@ -1,127 +1,118 @@
-import { strict as assert } from 'assert';
+/**
+ * @jest-environment node
+ * https://github.com/facebook/jest/issues/7780
+ */
 import { cloneDeep } from 'lodash';
 import KeyringController from 'eth-keyring-controller';
 import firstTimeState from '../first-time-state';
 import mockEncryptor from '../../../test/lib/mock-encryptor';
 import seedPhraseVerifier from './seed-phrase-verifier';
 
-describe('SeedPhraseVerifier', function () {
+describe('SeedPhraseVerifier', () => {
-  describe('verifyAccounts', function () {
+  describe('verifyAccounts', () => {
     const password = 'passw0rd1';
     const hdKeyTree = 'HD Key Tree';
 
     let keyringController;
     let primaryKeyring;
 
-    beforeEach(async function () {
+    beforeEach(async () => {
       keyringController = new KeyringController({
         initState: cloneDeep(firstTimeState),
         encryptor: mockEncryptor,
       });
 
-      assert(keyringController);
+      expect.any(keyringController);
 
       await keyringController.createNewVaultAndKeychain(password);
       primaryKeyring = keyringController.getKeyringsByType(hdKeyTree)[0];
     });
 
-    it('should be able to verify created account with seed words', async function () {
+    it('should be able to verify created account with seed words', async () => {
       const createdAccounts = await primaryKeyring.getAccounts();
-      assert.equal(createdAccounts.length, 1);
+      expect(createdAccounts).toHaveLength(1);
 
       const serialized = await primaryKeyring.serialize();
       const seedWords = serialized.mnemonic;
-      assert.notEqual(seedWords.length, 0);
+      expect(seedWords).not.toHaveLength(0);
 
       await seedPhraseVerifier.verifyAccounts(createdAccounts, seedWords);
     });
 
-    it('should be able to verify created account (upper case) with seed words', async function () {
+    it('should be able to verify created account (upper case) with seed words', async () => {
       const createdAccounts = await primaryKeyring.getAccounts();
-      assert.equal(createdAccounts.length, 1);
+      expect(createdAccounts).toHaveLength(1);
 
       const upperCaseAccounts = [createdAccounts[0].toUpperCase()];
 
       const serialized = await primaryKeyring.serialize();
       const seedWords = serialized.mnemonic;
-      assert.notEqual(seedWords.length, 0);
+      expect(seedWords).not.toHaveLength(0);
 
       await seedPhraseVerifier.verifyAccounts(upperCaseAccounts, seedWords);
     });
 
-    it('should be able to verify created account (lower case) with seed words', async function () {
+    it('should be able to verify created account (lower case) with seed words', async () => {
       const createdAccounts = await primaryKeyring.getAccounts();
-      assert.equal(createdAccounts.length, 1);
+      expect(createdAccounts).toHaveLength(1);
       const lowerCaseAccounts = [createdAccounts[0].toLowerCase()];
 
       const serialized = await primaryKeyring.serialize();
       const seedWords = serialized.mnemonic;
-      assert.notEqual(seedWords.length, 0);
+      expect(seedWords).not.toHaveLength(0);
 
       await seedPhraseVerifier.verifyAccounts(lowerCaseAccounts, seedWords);
     });
 
-    it('should return error with good but different seed words', async function () {
+    it('should return error with good but different seed words', async () => {
       const createdAccounts = await primaryKeyring.getAccounts();
-      assert.equal(createdAccounts.length, 1);
+      expect(createdAccounts).toHaveLength(1);
 
       await primaryKeyring.serialize();
       const seedWords =
         'debris dizzy just program just float decrease vacant alarm reduce speak stadium';
 
-      try {
+      await expect(async () => {
         await seedPhraseVerifier.verifyAccounts(createdAccounts, seedWords);
-        assert.fail('Should reject');
+      }).rejects.toThrow('Not identical accounts!');
-      } catch (err) {
-        assert.ok(
-          err.message.indexOf('Not identical accounts!') >= 0,
-          'Wrong error message',
-        );
-      }
     });
 
-    it('should return error with undefined existing accounts', async function () {
+    it('should return error with undefined existing accounts', async () => {
       const createdAccounts = await primaryKeyring.getAccounts();
-      assert.equal(createdAccounts.length, 1);
+      expect(createdAccounts).toHaveLength(1);
 
       await primaryKeyring.serialize();
       const seedWords =
         'debris dizzy just program just float decrease vacant alarm reduce speak stadium';
 
-      try {
+      await expect(async () => {
         await seedPhraseVerifier.verifyAccounts(undefined, seedWords);
-        assert.fail('Should reject');
+      }).rejects.toThrow('No created accounts defined.');
-      } catch (err) {
-        assert.equal(err.message, 'No created accounts defined.');
-      }
     });
 
-    it('should return error with empty accounts array', async function () {
+    it('should return error with empty accounts array', async () => {
       const createdAccounts = await primaryKeyring.getAccounts();
-      assert.equal(createdAccounts.length, 1);
+      expect(createdAccounts).toHaveLength(1);
 
       await primaryKeyring.serialize();
       const seedWords =
         'debris dizzy just program just float decrease vacant alarm reduce speak stadium';
 
-      try {
+      await expect(async () => {
         await seedPhraseVerifier.verifyAccounts([], seedWords);
-        assert.fail('Should reject');
+      }).rejects.toThrow('No created accounts defined.');
-      } catch (err) {
-        assert.equal(err.message, 'No created accounts defined.');
-      }
     });
 
-    it('should be able to verify more than one created account with seed words', async function () {
+    it('should be able to verify more than one created account with seed words', async () => {
       await keyringController.addNewAccount(primaryKeyring);
       await keyringController.addNewAccount(primaryKeyring);
 
       const createdAccounts = await primaryKeyring.getAccounts();
-      assert.equal(createdAccounts.length, 3);
+      expect(createdAccounts).toHaveLength(3);
 
       const serialized = await primaryKeyring.serialize();
       const seedWords = serialized.mnemonic;
-      assert.notEqual(seedWords.length, 0);
+      expect(seedWords).not.toHaveLength(0);
 
       await seedPhraseVerifier.verifyAccounts(createdAccounts, seedWords);
     });

app/scripts/lib/segment.js

@@ -33,10 +33,7 @@ const SEGMENT_FLUSH_INTERVAL = SECOND * 5;
  * @param {number} flushInterval - ms interval to flush queue and send to segment
  * @returns {SegmentInterface}
  */
-export const createSegmentMock = (
+export const createSegmentMock = (flushAt = SEGMENT_FLUSH_AT) => {
-  flushAt = SEGMENT_FLUSH_AT,
-  flushInterval = SEGMENT_FLUSH_INTERVAL,
-) => {
   const segmentMock = {
     // Internal queue to keep track of events and properly mimic segment's
     // queueing behavior.
@@ -77,8 +74,7 @@ export const createSegmentMock = (
       // noop
     },
   };
-  // Mimic the flushInterval behavior with an interval
+
-  setInterval(segmentMock.flush, flushInterval);
   return segmentMock;
 };
 

app/scripts/lib/typed-message-manager.test.js

@@ -1,9 +1,8 @@
-import { strict as assert } from 'assert';
 import sinon from 'sinon';
 import { TRANSACTION_STATUSES } from '../../../shared/constants/transaction';
 import TypedMessageManager from './typed-message-manager';
 
-describe('Typed Message Manager', function () {
+describe('Typed Message Manager', () => {
   let typedMessageManager,
     msgParamsV1,
     msgParamsV3,
@@ -14,7 +13,7 @@ describe('Typed Message Manager', function () {
 
   const address = '0xc42edfcc21ed14dda456aa0756c153f7985d8813';
 
-  beforeEach(async function () {
+  beforeEach(async () => {
     typedMessageManager = new TypedMessageManager({
       getCurrentChainId: sinon.fake.returns('0x1'),
       metricsEvent: sinon.fake(),
@@ -81,47 +80,48 @@ describe('Typed Message Manager', function () {
     numberMsgId = parseInt(msgId, 10);
   });
 
-  it('supports version 1 of signedTypedData', function () {
+  it('supports version 1 of signedTypedData', () => {
     typedMessageManager.addUnapprovedMessage(msgParamsV1, null, 'V1');
-    assert.equal(
+    expect(messages[messages.length - 1].msgParams.data).toStrictEqual(
-      messages[messages.length - 1].msgParams.data,
       msgParamsV1.data,
     );
   });
 
-  it('has params address', function () {
+  it('has params address', () => {
-    assert.equal(typedMsgs[msgId].msgParams.from, address);
+    expect(typedMsgs[msgId].msgParams.from).toStrictEqual(address);
   });
 
-  it('adds to unapproved messages and sets status to unapproved', function () {
+  it('adds to unapproved messages and sets status to unapproved', () => {
-    assert.equal(typedMsgs[msgId].status, TRANSACTION_STATUSES.UNAPPROVED);
+    expect(typedMsgs[msgId].status).toStrictEqual(
+      TRANSACTION_STATUSES.UNAPPROVED,
+    );
   });
 
-  it('validates params', function () {
+  it('validates params', async () => {
-    assert.doesNotThrow(() => {
+    await expect(() => {
       typedMessageManager.validateParams(messages[0].msgParams);
-    }, 'Does not throw with valid parameters');
+    }).not.toThrow();
   });
 
-  it('gets unapproved by id', function () {
+  it('gets unapproved by id', () => {
     const getMsg = typedMessageManager.getMsg(numberMsgId);
-    assert.equal(getMsg.id, numberMsgId);
+    expect(getMsg.id).toStrictEqual(numberMsgId);
   });
 
-  it('approves messages', async function () {
+  it('approves messages', async () => {
     const messageMetaMaskId = messages[0].msgParams;
     typedMessageManager.approveMessage(messageMetaMaskId);
-    assert.equal(messages[0].status, TRANSACTION_STATUSES.APPROVED);
+    expect(messages[0].status).toStrictEqual(TRANSACTION_STATUSES.APPROVED);
   });
 
-  it('sets msg status to signed and adds a raw sig to message details', function () {
+  it('sets msg status to signed and adds a raw sig to message details', () => {
     typedMessageManager.setMsgStatusSigned(numberMsgId, 'raw sig');
-    assert.equal(messages[0].status, TRANSACTION_STATUSES.SIGNED);
+    expect(messages[0].status).toStrictEqual(TRANSACTION_STATUSES.SIGNED);
-    assert.equal(messages[0].rawSig, 'raw sig');
+    expect(messages[0].rawSig).toStrictEqual('raw sig');
   });
 
-  it('rejects message', function () {
+  it('rejects message', () => {
     typedMessageManager.rejectMsg(numberMsgId);
-    assert.equal(messages[0].status, TRANSACTION_STATUSES.REJECTED);
+    expect(messages[0].status).toStrictEqual(TRANSACTION_STATUSES.REJECTED);
   });
 });

app/scripts/lib/util.test.js

@@ -1,5 +1,3 @@
-import { strict as assert } from 'assert';
-import sinon from 'sinon';
 import { isPrefixedFormattedHexString } from '../../../shared/modules/network.utils';
 import {
   ENVIRONMENT_TYPE_POPUP,
@@ -13,201 +11,154 @@ import {
 } from '../../../shared/constants/app';
 import { getEnvironmentType, getPlatform } from './util';
 
-describe('app utils', function () {
+describe('app utils', () => {
-  describe('getEnvironmentType', function () {
+  describe('getEnvironmentType', () => {
-    it('should return popup type', function () {
+    it('should return popup type', () => {
       const environmentType = getEnvironmentType(
         'http://extension-id/popup.html',
       );
-      assert.equal(environmentType, ENVIRONMENT_TYPE_POPUP);
+      expect(environmentType).toStrictEqual(ENVIRONMENT_TYPE_POPUP);
     });
 
-    it('should return notification type', function () {
+    it('should return notification type', () => {
       const environmentType = getEnvironmentType(
         'http://extension-id/notification.html',
       );
-      assert.equal(environmentType, ENVIRONMENT_TYPE_NOTIFICATION);
+      expect(environmentType).toStrictEqual(ENVIRONMENT_TYPE_NOTIFICATION);
     });
 
-    it('should return fullscreen type for home.html', function () {
+    it('should return fullscreen type for home.html', () => {
       const environmentType = getEnvironmentType(
         'http://extension-id/home.html',
       );
-      assert.equal(environmentType, ENVIRONMENT_TYPE_FULLSCREEN);
+      expect(environmentType).toStrictEqual(ENVIRONMENT_TYPE_FULLSCREEN);
     });
 
-    it('should return fullscreen type for phishing.html', function () {
+    it('should return fullscreen type for phishing.html', () => {
       const environmentType = getEnvironmentType(
         'http://extension-id/phishing.html',
       );
-      assert.equal(environmentType, ENVIRONMENT_TYPE_FULLSCREEN);
+      expect(environmentType).toStrictEqual(ENVIRONMENT_TYPE_FULLSCREEN);
     });
 
-    it('should return background type', function () {
+    it('should return background type', () => {
       const environmentType = getEnvironmentType(
         'http://extension-id/_generated_background_page.html',
       );
-      assert.equal(environmentType, ENVIRONMENT_TYPE_BACKGROUND);
+      expect(environmentType).toStrictEqual(ENVIRONMENT_TYPE_BACKGROUND);
     });
 
-    it('should return the correct type for a URL with a hash fragment', function () {
+    it('should return the correct type for a URL with a hash fragment', () => {
       const environmentType = getEnvironmentType(
         'http://extension-id/popup.html#hash',
       );
-      assert.equal(environmentType, ENVIRONMENT_TYPE_POPUP);
+      expect(environmentType).toStrictEqual(ENVIRONMENT_TYPE_POPUP);
     });
 
-    it('should return the correct type for a URL with query parameters', function () {
+    it('should return the correct type for a URL with query parameters', () => {
       const environmentType = getEnvironmentType(
         'http://extension-id/popup.html?param=foo',
       );
-      assert.equal(environmentType, ENVIRONMENT_TYPE_POPUP);
+      expect(environmentType).toStrictEqual(ENVIRONMENT_TYPE_POPUP);
     });
 
-    it('should return the correct type for a URL with query parameters and a hash fragment', function () {
+    it('should return the correct type for a URL with query parameters and a hash fragment', () => {
       const environmentType = getEnvironmentType(
         'http://extension-id/popup.html?param=foo#hash',
       );
-      assert.equal(environmentType, ENVIRONMENT_TYPE_POPUP);
+      expect(environmentType).toStrictEqual(ENVIRONMENT_TYPE_POPUP);
     });
   });
 
-  describe('isPrefixedFormattedHexString', function () {
+  describe('isPrefixedFormattedHexString', () => {
-    it('should return true for valid hex strings', function () {
+    it('should return true for valid hex strings', () => {
-      assert.equal(
+      expect(isPrefixedFormattedHexString('0x1')).toStrictEqual(true);
-        isPrefixedFormattedHexString('0x1'),
-        true,
-        'should return true',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString('0xa')).toStrictEqual(true);
-        isPrefixedFormattedHexString('0xa'),
-        true,
-        'should return true',
-      );
 
-      assert.equal(
+      expect(
         isPrefixedFormattedHexString('0xabcd1123fae909aad87452'),
-        true,
+      ).toStrictEqual(true);
-        'should return true',
-      );
     });
 
-    it('should return false for invalid hex strings', function () {
+    it('should return false for invalid hex strings', () => {
-      assert.equal(
+      expect(isPrefixedFormattedHexString('0x')).toStrictEqual(false);
-        isPrefixedFormattedHexString('0x'),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString('0x0')).toStrictEqual(false);
-        isPrefixedFormattedHexString('0x0'),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString('0x01')).toStrictEqual(false);
-        isPrefixedFormattedHexString('0x01'),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString(' 0x1')).toStrictEqual(false);
-        isPrefixedFormattedHexString(' 0x1'),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString('0x1 ')).toStrictEqual(false);
-        isPrefixedFormattedHexString('0x1 '),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString('0x1afz')).toStrictEqual(false);
-        isPrefixedFormattedHexString('0x1afz'),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString('z')).toStrictEqual(false);
-        isPrefixedFormattedHexString('z'),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString(2)).toStrictEqual(false);
-        isPrefixedFormattedHexString(2),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString(['0x1'])).toStrictEqual(false);
-        isPrefixedFormattedHexString(['0x1']),
-        false,
-        'should return false',
-      );
 
-      assert.equal(
+      expect(isPrefixedFormattedHexString()).toStrictEqual(false);
-        isPrefixedFormattedHexString(),
-        false,
-        'should return false',
-      );
     });
   });
 
-  describe('getPlatform', function () {
+  describe('getPlatform', () => {
-    const setBrowserSpecificWindow = (browser) => {
+    let userAgent, setBrowserSpecificWindow;
-      switch (browser) {
+
-        case 'firefox': {
+    beforeEach(() => {
-          sinon.stub(window, 'navigator').value({
+      userAgent = jest.spyOn(window.navigator, 'userAgent', 'get');
-            userAgent:
+
+      setBrowserSpecificWindow = (browser) => {
+        switch (browser) {
+          case 'firefox': {
+            userAgent.mockReturnValue(
               'Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:95.0) Gecko/20100101 Firefox/95.0',
-          });
+            );
-          break;
+            break;
-        }
+          }
-        case 'edge': {
+          case 'edge': {
-          sinon.stub(window, 'navigator').value({
+            userAgent.mockReturnValue(
-            userAgent:
               'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.54 Safari/537.36 Edg/95.0.1020.30',
-          });
+            );
-          break;
+            break;
-        }
+          }
-        case 'opera': {
+          case 'opera': {
-          sinon.stub(window, 'navigator').value({
+            userAgent.mockReturnValue(
-            userAgent:
               'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.81 Safari/537.36 OPR/80.0.4170.63',
-          });
+            );
-          break;
+
-        }
+            break;
-        default: {
+          }
-          sinon.stub(window, 'navigator').value({
+          default: {
-            userAgent:
+            userAgent.mockReturnValue(
               'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.81 Safari/537.36',
-          });
+            );
-          break;
+            break;
+          }
         }
-      }
+      };
-    };
+    });
 
-    it('should detect Firefox', function () {
+    it('should detect Firefox', () => {
       setBrowserSpecificWindow('firefox');
-      assert.equal(getPlatform(), PLATFORM_FIREFOX);
+      expect(getPlatform()).toStrictEqual(PLATFORM_FIREFOX);
     });
 
-    it('should detect Edge', function () {
+    it('should detect Edge', () => {
       setBrowserSpecificWindow('edge');
-      assert.equal(getPlatform(), PLATFORM_EDGE);
+      expect(getPlatform()).toStrictEqual(PLATFORM_EDGE);
     });
 
-    it('should detect Opera', function () {
+    it('should detect Opera', () => {
       setBrowserSpecificWindow('opera');
-      assert.equal(getPlatform(), PLATFORM_OPERA);
+      expect(getPlatform()).toStrictEqual(PLATFORM_OPERA);
     });
 
-    it('should detect Chrome', function () {
+    it('should detect Chrome', () => {
       setBrowserSpecificWindow('chrome');
-      assert.equal(getPlatform(), PLATFORM_CHROME);
+      expect(getPlatform()).toStrictEqual(PLATFORM_CHROME);
     });
   });
 });

jest.config.js

@@ -21,6 +21,7 @@ module.exports = {
     '<rootDir>/shared/**/*.test.js',
     '<rootDir>/app/scripts/migrations/*.test.js',
     '<rootDir>/app/scripts/platforms/*.test.js',
+    '<rootDir>/app/scripts/lib/**/*.test.js',
   ],
   testTimeout: 2500,
   transform: {

package.json

@@ -27,7 +27,7 @@
     "test:unit": "./test/test-unit-combined.sh",
     "test:unit:jest": "./test/test-unit-jest.sh",
     "test:unit:global": "mocha test/unit-global/*.test.js",
-    "test:unit:mocha": "mocha './app/**/*.test.js'",
+    "test:unit:mocha": "mocha --config '.mocharc.js' './app/**/*.test.js'",
     "test:unit:lax": "mocha --config '.mocharc.lax.js' './app/**/*.test.js'",
     "test:unit:strict": "mocha './app/scripts/controllers/permissions/*.test.js'",
     "test:e2e:chrome": "SELENIUM_BROWSER=chrome node test/e2e/run-all.js",