refactor(x/auth): allow empty public keys for GetSignBytesAdapter (backport #19651) (#19675)

Co-authored-by: mmsqe <mavis@crypto.com>
Co-authored-by: Julien Robert <julien@rbrt.fr>

CHANGELOG.md

@@ -40,6 +40,10 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ## [v0.50.5](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.50.5) - 2024-XX-XX
 
+### Improvements
+
+* (x/auth) [#19651](https://github.com/cosmos/cosmos-sdk/pull/19651) Allow empty public keys in `GetSignBytesAdapter`.
+
 ### Bug Fixes
 
 * (x/auth) [#19549](https://github.com/cosmos/cosmos-sdk/pull/19549) Accept custom get signers when injecting `x/auth/tx`.

x/auth/signing/adapter.go

@@ -41,20 +41,24 @@ func GetSignBytesAdapter(
 		return nil, err
 	}
 
-	anyPk, err := codectypes.NewAnyWithValue(signerData.PubKey)
-	if err != nil {
-		return nil, err
-	}
+	var pubKey *anypb.Any
+	if signerData.PubKey != nil {
+		anyPk, err := codectypes.NewAnyWithValue(signerData.PubKey)
+		if err != nil {
+			return nil, err
+		}
 
+		pubKey = &anypb.Any{
+			TypeUrl: anyPk.TypeUrl,
+			Value:   anyPk.Value,
+		}
+	}
 	txSignerData := txsigning.SignerData{
 		ChainID:       signerData.ChainID,
 		AccountNumber: signerData.AccountNumber,
 		Sequence:      signerData.Sequence,
 		Address:       signerData.Address,
-		PubKey: &anypb.Any{
-			TypeUrl: anyPk.TypeUrl,
-			Value:   anyPk.Value,
-		},
+		PubKey:        pubKey,
 	}
 	// Generate the bytes to be signed.
 	return handlerMap.GetSignBytes(ctx, txSignMode, txSignerData, txData)

x/auth/signing/adapter_test.go

@@ -0,0 +1,33 @@
+package signing_test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/cosmos/cosmos-sdk/testutil/testdata"
+	moduletestutil "github.com/cosmos/cosmos-sdk/types/module/testutil"
+	"github.com/cosmos/cosmos-sdk/types/tx/signing"
+	authsign "github.com/cosmos/cosmos-sdk/x/auth/signing"
+)
+
+func TestGetSignBytesAdapterNoPublicKey(t *testing.T) {
+	encodingConfig := moduletestutil.MakeTestEncodingConfig()
+	txConfig := encodingConfig.TxConfig
+	_, _, addr := testdata.KeyTestPubAddr()
+	signerData := authsign.SignerData{
+		Address:       addr.String(),
+		ChainID:       "test-chain",
+		AccountNumber: 11,
+		Sequence:      15,
+	}
+	w := txConfig.NewTxBuilder()
+	_, err := authsign.GetSignBytesAdapter(
+		context.Background(),
+		txConfig.SignModeHandler(),
+		signing.SignMode_SIGN_MODE_DIRECT,
+		signerData,
+		w.GetTx())
+	require.NoError(t, err)
+}