From d27736589dd39a239813cec1b8881b750af40649 Mon Sep 17 00:00:00 2001
From: Simon Warta <simon@warta.it>
Date: Sat, 7 Oct 2023 00:35:19 +0300
Subject: [PATCH] Add decodeOptionalPubkey and use it

---
 packages/proto-signing/src/index.ts  |  2 +-
 packages/proto-signing/src/pubkey.ts | 26 +++++++++++++++++++++++++-
 packages/stargate/src/accounts.ts    |  4 ++--
 3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/packages/proto-signing/src/index.ts b/packages/proto-signing/src/index.ts
index c34d0ff7..9c25e61a 100644
--- a/packages/proto-signing/src/index.ts
+++ b/packages/proto-signing/src/index.ts
@@ -8,7 +8,7 @@ export {
 } from "./directsecp256k1hdwallet";
 export { DirectSecp256k1Wallet } from "./directsecp256k1wallet";
 export { makeCosmoshubPath } from "./paths";
-export { anyToSinglePubkey, decodePubkey, encodePubkey } from "./pubkey";
+export { anyToSinglePubkey, decodeOptionalPubkey, decodePubkey, encodePubkey } from "./pubkey";
 export {
   DecodeObject,
   EncodeObject,
diff --git a/packages/proto-signing/src/pubkey.ts b/packages/proto-signing/src/pubkey.ts
index 8fc935f9..8ccaa943 100644
--- a/packages/proto-signing/src/pubkey.ts
+++ b/packages/proto-signing/src/pubkey.ts
@@ -97,6 +97,30 @@ export function decodePubkey(pubkey: Any): Pubkey {
       return out;
     }
     default:
-      throw new Error(`Pubkey type_url ${pubkey.typeUrl} not recognized`);
+      throw new Error(`Pubkey type URL '${pubkey.typeUrl}' not recognized`);
+  }
+}
+
+/**
+ * Decodes an optional pubkey from a protobuf `Any` into `Pubkey | null`.
+ * This supports single pubkeys such as Cosmos ed25519 and secp256k1 keys
+ * as well as multisig threshold pubkeys.
+ */
+export function decodeOptionalPubkey(pubkey: Any | null | undefined): Pubkey | null {
+  if (!pubkey) return null;
+  if (pubkey.typeUrl) {
+    if (pubkey.value.length) {
+      // both set
+      return decodePubkey(pubkey);
+    } else {
+      throw new Error(`Pubkey is an Any with type URL '${pubkey.typeUrl}' but an empty value`);
+    }
+  } else {
+    if (pubkey.value.length) {
+      throw new Error(`Pubkey is an Any with an empty type URL but a value set`);
+    } else {
+      // both unset, assuming this empty instance means null
+      return null;
+    }
   }
 }
diff --git a/packages/stargate/src/accounts.ts b/packages/stargate/src/accounts.ts
index a0cac7ca..95a765ab 100644
--- a/packages/stargate/src/accounts.ts
+++ b/packages/stargate/src/accounts.ts
@@ -1,6 +1,6 @@
 import { Pubkey } from "@cosmjs/amino";
 import { Uint64 } from "@cosmjs/math";
-import { decodePubkey } from "@cosmjs/proto-signing";
+import { decodeOptionalPubkey } from "@cosmjs/proto-signing";
 import { assert } from "@cosmjs/utils";
 import { BaseAccount, ModuleAccount } from "cosmjs-types/cosmos/auth/v1beta1/auth";
 import {
@@ -25,7 +25,7 @@ function uint64FromProto(input: number | bigint): Uint64 {
 
 function accountFromBaseAccount(input: BaseAccount): Account {
   const { address, pubKey, accountNumber, sequence } = input;
-  const pubkey = pubKey ? decodePubkey(pubKey) : null;
+  const pubkey = decodeOptionalPubkey(pubKey);
   return {
     address: address,
     pubkey: pubkey,