Run tests with mocha instead of jest

__tests__/helpers/assets.test.ts

@@ -2,6 +2,8 @@
  * Unit tests for helpers/assets.
  */
 
+import expect from 'expect';
+
 import {
   ASSET_ID_MAP,
   COLLATERAL_ASSET_ID,

__tests__/helpers/crypto.test.ts

@@ -2,6 +2,8 @@
  * Unit tests for helpers/crypto.
  */
 
+import expect from 'expect';
+
 import { KeyPair } from '../../src/types';
 
 // Module under test.

__tests__/helpers/misc.test.ts

@@ -2,6 +2,8 @@
  * Unit tests for helpers/misc.
  */
 
+import expect from 'expect';
+
 // Module under test.
 import {
   nonceFromClientId,

__tests__/keys.test.ts

@@ -2,6 +2,8 @@
  * Unit tests for keys.ts.
  */
 
+import expect from 'expect';
+
 import {
   KeyPair,
 } from '../src/types';

__tests__/signable/api-request.test.ts

@@ -2,6 +2,8 @@
  * Unit tests for signable/api-request.ts.
  */
 
+import expect from 'expect';
+
 import {
   ApiMethod,
   ApiRequestParams,

__tests__/signable/oracle-price.test.ts

@@ -2,6 +2,8 @@
  * Unit tests for signable/oracle-price.ts.
  */
 
+import expect from 'expect';
+
 import {
   KeyPair,
   OraclePriceWithAssetId,

__tests__/signable/order.test.ts

@@ -3,6 +3,7 @@
  */
 
 import Big, { RoundingMode } from 'big.js';
+import expect from 'expect';
 
 import {
   OrderWithClientId,
@@ -189,7 +190,7 @@ describe('SignableOrder', () => {
 
   it('end-to-end', () => {
     // Repeat some number of times.
-    for (let i = 0; i < 1; i++) {
+    for (let i = 0; i < 3; i++) {
       const keyPair: KeyPair = generateKeyPairUnsafe();
       const signableOrder = SignableOrder.fromOrder(mockOrder);
       const signature = signableOrder.sign(keyPair.privateKey);

__tests__/signable/withdrawal.test.ts

@@ -2,6 +2,8 @@
  * Unit tests for signable/withdrawals.ts.
  */
 
+import expect from 'expect';
+
 import {
   KeyPair,
   StarkwareWithdrawal,
@@ -119,7 +121,7 @@ describe('SignableWithdrawal', () => {
 
   it('end-to-end', () => {
     // Repeat some number of times.
-    for (let i = 0; i < 1; i++) {
+    for (let i = 0; i < 3; i++) {
       const keyPair: KeyPair = generateKeyPairUnsafe();
       const signableWithdrawal = SignableWithdrawal.fromWithdrawal(mockWithdrawal);
       const signature = signableWithdrawal.sign(keyPair.privateKey);

__tests__/util.test.ts

@@ -2,6 +2,8 @@
  * Unit tests for util.ts.
  */
 
+import expect from 'expect';
+
 // Module under test.
 import {
   normalizeHex32,