From 7eb53ea17c2bc450a7ef875122e7dd3a8ebc948d Mon Sep 17 00:00:00 2001
From: Simon Warta <simon@warta.it>
Date: Wed, 24 Mar 2021 10:11:35 +0100
Subject: [PATCH] Support explicit signer data in SigningStargateClient.sign

---
 .../signingstargateclient.multisig.spec.ts    | 10 +++----
 .../stargate/src/signingstargateclient.ts     | 26 +++++++++++++------
 2 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/packages/stargate/src/signingstargateclient.multisig.spec.ts b/packages/stargate/src/signingstargateclient.multisig.spec.ts
index 70b6d660..117ea680 100644
--- a/packages/stargate/src/signingstargateclient.multisig.spec.ts
+++ b/packages/stargate/src/signingstargateclient.multisig.spec.ts
@@ -127,19 +127,19 @@ describe("SigningStargateClient multisig", () => {
     const {
       bodyBytes,
       signatures: [signature0],
-    } = await client0.signAmino(faucet.address0, [msg], fee, memo, signerData);
+    } = await client0.sign(faucet.address0, [msg], fee, memo, signerData);
     const {
       signatures: [signature1],
-    } = await client1.signAmino(faucet.address1, [msg], fee, memo, signerData);
+    } = await client1.sign(faucet.address1, [msg], fee, memo, signerData);
     const {
       signatures: [signature2],
-    } = await client2.signAmino(faucet.address2, [msg], fee, memo, signerData);
+    } = await client2.sign(faucet.address2, [msg], fee, memo, signerData);
     const {
       signatures: [signature3],
-    } = await client3.signAmino(faucet.address3, [msg], fee, memo, signerData);
+    } = await client3.sign(faucet.address3, [msg], fee, memo, signerData);
     const {
       signatures: [signature4],
-    } = await client4.signAmino(faucet.address4, [msg], fee, memo, signerData);
+    } = await client4.sign(faucet.address4, [msg], fee, memo, signerData);
 
     const signatures = new Map<string, Uint8Array>([
       [address0, signature0],
diff --git a/packages/stargate/src/signingstargateclient.ts b/packages/stargate/src/signingstargateclient.ts
index 1c66ba19..c505b1f9 100644
--- a/packages/stargate/src/signingstargateclient.ts
+++ b/packages/stargate/src/signingstargateclient.ts
@@ -190,27 +190,37 @@ export class SigningStargateClient extends StargateClient {
    * creates a single signature and assembles the signed transaction.
    *
    * The sign mode (SIGN_MODE_DIRECT or SIGN_MODE_LEGACY_AMINO_JSON) is determined by this client's signer.
+   *
+   * You can pass signer data (account number, sequence and chain ID) explicitly instead of querying them
+   * from the chain. This is needed when signing for a multisig account, but it also allows for offline signing
+   * (which probably fails right now because in other places SigningStargateClient assumes you are online).
    */
   public async sign(
     signerAddress: string,
     messages: readonly EncodeObject[],
     fee: StdFee,
     memo: string,
+    explicitSignerData?: SignerData,
   ): Promise<TxRaw> {
-    const accountFromChain = await this.getAccountUnverified(signerAddress);
-    if (!accountFromChain) {
-      throw new Error("Account not found");
+    let signerData: SignerData;
+    if (explicitSignerData) {
+      signerData = explicitSignerData;
+    } else {
+      const accountFromChain = await this.getAccountUnverified(signerAddress);
+      if (!accountFromChain) {
+        throw new Error("Account not found");
+      }
+      const { accountNumber, sequence } = accountFromChain;
+      const chainId = await this.getChainId();
+      signerData = { accountNumber, sequence, chainId };
     }
-    const { accountNumber, sequence } = accountFromChain;
-    const chainId = await this.getChainId();
-    const signerData: SignerData = { accountNumber, sequence, chainId };
 
     return isOfflineDirectSigner(this.signer)
       ? this.signDirect(signerAddress, messages, fee, memo, signerData)
       : this.signAmino(signerAddress, messages, fee, memo, signerData);
   }
 
-  public async signAmino(
+  private async signAmino(
     signerAddress: string,
     messages: readonly EncodeObject[],
     fee: StdFee,
@@ -253,7 +263,7 @@ export class SigningStargateClient extends StargateClient {
     });
   }
 
-  public async signDirect(
+  private async signDirect(
     signerAddress: string,
     messages: readonly EncodeObject[],
     fee: StdFee,