fix(abstract-eth): return eip 191 encoded message as a hex string

Ticket: SC-1424

BREAKING CHANGE: messageEncoded is now encoded as a hex string

Author: sbplat

examples/js/send-message.js

@@ -16,21 +16,20 @@ const walletId = null;
 const walletPassphrase = '';
 
 Promise.coroutine(function* () {
-    bitgo.authenticateWithAccessToken({ accessToken: accessToken });
+  bitgo.authenticateWithAccessToken({ accessToken: accessToken });
 
-    const walletInstance = yield basecoin.wallets().get({ id: walletId });
+  const walletInstance = yield basecoin.wallets().get({ id: walletId });
 
-    const messageRaw = 'Shamir has too many secrets';
-    const messageEncoded = `\u0019Ethereum Signed Message:\n${messageRaw.length}${messageRaw}`;
+  const messageRaw = 'Shamir has too many secrets';
+  const messageEncoded = basecoin.encodeMessage(messageRaw);
 
-    const messageTxn = yield walletInstance.signMessage({
-        message: {
-            messageRaw,
-            messageEncoded,
-        },
-        walletPassphrase,
-    })
-
-    console.log(messageTxn);
+  const messageTxn = yield walletInstance.signMessage({
+    message: {
+      messageRaw,
+      messageEncoded,
+    },
+    walletPassphrase,
+  });
 
+  console.log(messageTxn);
 })();

modules/abstract-eth/src/abstractEthLikeNewCoins.ts

@@ -2430,11 +2430,11 @@ export abstract class AbstractEthLikeNewCoins extends AbstractEthLikeCoin {
   /**
    * Transform message to accommodate specific blockchain requirements.
    * @param {string} message - the message to prepare
-   * @return {string} the prepared message.
+   * @return {string} the prepared message as a hex encoded string.
    */
   encodeMessage(message: string): string {
     const prefix = `\u0019Ethereum Signed Message:\n${message.length}`;
-    return prefix.concat(message);
+    return Buffer.from(prefix.concat(message)).toString('hex');
   }
 
   /**

modules/bitgo/test/v2/unit/wallet.ts

@@ -3448,7 +3448,7 @@ describe('V2 Wallet:', function () {
         signature: txHash,
         messageRaw,
         coin: 'teth',
-        messageEncoded: '\u0019Ethereum Signed Message:\n4test',
+        messageEncoded: Buffer.from('\u0019Ethereum Signed Message:\n4test').toString('hex'),
       };
 
       beforeEach(async function () {
@@ -3499,7 +3499,7 @@ describe('V2 Wallet:', function () {
           signMessage.should.deepEqual(expectedWithCoinField);
           const actualArg = signMessageTssSpy.getCalls()[0].args[0] as WalletSignMessageOptions;
           actualArg.message?.messageEncoded?.should.equal(
-            `\u0019Ethereum Signed Message:\n${messageRaw.length}${messageRaw}`
+            Buffer.from(`\u0019Ethereum Signed Message:\n${messageRaw.length}${messageRaw}`).toString('hex')
           );
         });
 
@@ -3516,7 +3516,7 @@ describe('V2 Wallet:', function () {
           signMessage.should.deepEqual(expectedWithCoinField);
           const actualArg = signMessageTssSpy.getCalls()[0].args[0] as WalletSignMessageOptions;
           actualArg.message?.messageEncoded?.should.equal(
-            `\u0019Ethereum Signed Message:\n${messageRaw.length}${messageRaw}`
+            Buffer.from(`\u0019Ethereum Signed Message:\n${messageRaw.length}${messageRaw}`).toString('hex')
           );
         });
 
@@ -3532,7 +3532,7 @@ describe('V2 Wallet:', function () {
           signMessage.should.deepEqual(expectedWithCoinField);
           const actualArg = signMessageTssSpy.getCalls()[0].args[0] as WalletSignMessageOptions;
           actualArg.message?.messageEncoded?.should.equal(
-            `\u0019Ethereum Signed Message:\n${messageRaw.length}${messageRaw}`
+            Buffer.from(`\u0019Ethereum Signed Message:\n${messageRaw.length}${messageRaw}`).toString('hex')
           );
         });
 

modules/sdk-core/src/bitgo/wallet/wallet.ts

@@ -3497,7 +3497,7 @@ export class Wallet implements IWallet {
         reqId: params.reqId || new RequestTracer(),
         messageRaw: params.message.messageRaw,
         messageEncoded: params.message.messageEncoded,
-        bufferToSign: Buffer.from(params.message.messageEncoded ?? ''),
+        bufferToSign: Buffer.from(params.message.messageEncoded ?? '', 'hex'),
       });
       assert(signedMessageRequest.messages, 'Unable to find messages in signedMessageRequest');
       assert(