From 016b8b18092443c5c0df9981c9ae9cbcc390bfb8 Mon Sep 17 00:00:00 2001
From: Jaco Greeff <jacogr@gmail.com>
Date: Sat, 13 Oct 2018 17:12:58 +0200
Subject: [PATCH] Warn on unexpected decoded prefix (#223)

---
 packages/keyring/src/address/decode.spec.js | 4 ++--
 packages/keyring/src/address/decode.ts      | 6 +++++-
 packages/keyring/src/address/defaults.ts    | 1 +
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/packages/keyring/src/address/decode.spec.js b/packages/keyring/src/address/decode.spec.js
index d9ce34dec..674d34997 100644
--- a/packages/keyring/src/address/decode.spec.js
+++ b/packages/keyring/src/address/decode.spec.js
@@ -63,9 +63,9 @@ describe('decode', () => {
     ).toEqual(new Uint8Array([42, 44, 10, 0, 0, 0, 0, 0]));
   });
 
-  it('fails when prefix is invalid', () => {
+  it('allows invalid prefix (in list)', () => {
     expect(
-      () => decode('BXHKtJjKdXjvbvTg6qK275sgcKKq8dnU38MQQAiR3LN2stP')
+      () => decode('6GfvWUvHvU8otbZ7sFhXH4eYeMcKdUkL61P3nFy52efEPVUx')
     ).toThrow(/address prefix/);
   });
 
diff --git a/packages/keyring/src/address/decode.ts b/packages/keyring/src/address/decode.ts
index afb19f813..ab6824144 100644
--- a/packages/keyring/src/address/decode.ts
+++ b/packages/keyring/src/address/decode.ts
@@ -26,9 +26,13 @@ export default function decode (encoded: string | Uint8Array, prefix: Prefix = d
   const error = (message: string) =>
     `Decoding ${encoded}: ${message}`;
 
-  assert(decoded[0] === prefix, error('Invalid decoded address prefix'));
+  assert(defaults.allowedPrefix.includes(decoded[0] as Prefix), error('Invalid decoded address prefix'));
   assert(defaults.allowedEncodedLengths.includes(decoded.length), error('Invalid decoded address length'));
 
+  if (decoded[0] !== prefix) {
+    console.log(`WARN: Expected ${prefix}, found ${decoded[0]}`);
+  }
+
   const isPublicKey = decoded.length === 35;
 
   // non-publicKeys has 1 byte checksums, else default to 2
diff --git a/packages/keyring/src/address/defaults.ts b/packages/keyring/src/address/defaults.ts
index 59cab5223..409c77c95 100644
--- a/packages/keyring/src/address/defaults.ts
+++ b/packages/keyring/src/address/defaults.ts
@@ -8,5 +8,6 @@ export default {
   allowedDecodedLengths: [1, 2, 4, 8, 32],
   // publicKey has prefix + 2 checksum bytes, short only prefix + 1 checksum byte
   allowedEncodedLengths: [3, 4, 6, 10, 35],
+  allowedPrefix: [0, 1, 42, 43, 68, 69] as Array<Prefix>,
   prefix: 42 as Prefix
 };