add test comparing new implementation with old to ensure account deri…

…vation is consistent

package.json

@@ -39,6 +39,7 @@
     "@metamask/eslint-config": "^8.0.0",
     "@metamask/eslint-config-jest": "^9.0.0",
     "@metamask/eslint-config-nodejs": "^8.0.0",
+    "@metamask/eth-hd-keyring": "4.0.2",
     "@types/jest": "^27.4.1",
     "eslint": "^7.32.0",
     "eslint-config-prettier": "^8.3.0",

test/index.js

@@ -9,6 +9,7 @@ const {
 const { wordlist } = require('@metamask/scure-bip39/dist/wordlists/english');
 const oldMMForkBIP39 = require('@metamask/bip39');
 const { isValidAddress } = require('@ethereumjs/util');
+const OldHdKeyring = require('@metamask/eth-hd-keyring');
 const HdKeyring = require('..');
 
 // Sample account:
@@ -26,6 +27,28 @@ describe('hd-keyring', () => {
     keyring = new HdKeyring();
   });
 
+  describe('compare old bip39 implementation with new', () => {
+    it('should derive the same accounts from the same mnemonics', () => {
+      const mnemonics = [];
+      for (let i = 0; i < 99; i++) {
+        mnemonics.push(oldMMForkBIP39.generateMnemonic());
+      }
+
+      mnemonics.forEach(async (mnemonic) => {
+        const newHDKeyring = new HdKeyring({ mnemonic, numberOfAccounts: 3 });
+        const oldHDKeyring = new OldHdKeyring({
+          mnemonic,
+          numberOfAccounts: 3,
+        });
+        const newAccounts = await newHDKeyring.getAccounts();
+        const oldAccounts = await oldHDKeyring.getAccounts();
+        expect(newAccounts[0]).toStrictEqual(oldAccounts[0]);
+        expect(newAccounts[1]).toStrictEqual(oldAccounts[1]);
+        expect(newAccounts[2]).toStrictEqual(oldAccounts[2]);
+      });
+    });
+  });
+
   describe('constructor', () => {
     it('constructs with a typeof string mnemonic', async () => {
       keyring = new HdKeyring({

yarn.lock

@@ -617,6 +617,17 @@
   resolved "https://registry.yarnpkg.com/@metamask/eslint-config/-/eslint-config-8.0.0.tgz#f4e3bcd6b37ec135b5a72902b0526cba2a6b5a4d"
   integrity sha512-ZO9B3ohNhjomrufNAkxnDXV46Kut7NKzri7itDxUzHJncNtI1of7ewWh6fKPl/hr6Al6Gd7WgjPdJZGFpzKPQw==
 
+"@metamask/eth-hd-keyring@4.0.2":
+  version "4.0.2"
+  resolved "https://registry.yarnpkg.com/@metamask/eth-hd-keyring/-/eth-hd-keyring-4.0.2.tgz#0a81556a556b361755c8d6fb5aced1ce5be0331c"
+  integrity sha512-v47VOTCCmZUZ6uxM5tQNoasQjLdrZADmgph2fhk4m7zKVUxDvYFU7FJT3Rm55fk8mg+dKSbEObDriqbdWeBbcA==
+  dependencies:
+    "@metamask/bip39" "^4.0.0"
+    "@metamask/eth-sig-util" "^4.0.0"
+    eth-simple-keyring "^4.2.0"
+    ethereumjs-util "^7.0.9"
+    ethereumjs-wallet "^1.0.1"
+
 "@metamask/eth-sig-util@^4.0.0":
   version "4.0.1"
   resolved "https://registry.yarnpkg.com/@metamask/eth-sig-util/-/eth-sig-util-4.0.1.tgz#3ad61f6ea9ad73ba5b19db780d40d9aae5157088"