fix: support custom tx config and sign modes

x/auth/tx/config.go

@@ -34,6 +34,26 @@ func NewTxConfig(protoCodec codec.ProtoCodecMarshaler, enabledSignModes []signin
 	}
 }
 
+// CustomTxConfig returns a new protobuf TxConfig using the provided ProtoCodec, sign modes, and (de/en)coders. The
+// first enabled sign mode will become the default sign mode.
+func CustomTxConfig(
+	handler signing.SignModeHandler,
+	decoder sdk.TxDecoder,
+	encoder sdk.TxEncoder,
+	jsonDecoder sdk.TxDecoder,
+	jsonEncoder sdk.TxEncoder,
+	protoCodec codec.ProtoCodecMarshaler,
+) client.TxConfig {
+	return &config{
+		handler:     handler,
+		decoder:     decoder,
+		encoder:     encoder,
+		jsonDecoder: jsonDecoder,
+		jsonEncoder: jsonEncoder,
+		protoCodec:  protoCodec,
+	}
+}
+
 func (g config) NewTxBuilder() client.TxBuilder {
 	return newBuilder(g.protoCodec)
 }

x/auth/tx/direct.go

@@ -10,11 +10,17 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/auth/signing"
 )
 
+var _ signing.SignModeHandler = signModeDirectHandler{}
+
+// NewSignModeDirectHandler creates a new Direct SignModeHandler
+// instance.
+func NewSignModeDirectHandler() signing.SignModeHandler {
+	return signModeDirectHandler{}
+}
+
 // signModeDirectHandler defines the SIGN_MODE_DIRECT SignModeHandler
 type signModeDirectHandler struct{}
 
-var _ signing.SignModeHandler = signModeDirectHandler{}
-
 // DefaultMode implements SignModeHandler.DefaultMode
 func (signModeDirectHandler) DefaultMode() signingtypes.SignMode {
 	return signingtypes.SignMode_SIGN_MODE_DIRECT

x/auth/tx/direct_aux.go

@@ -12,6 +12,12 @@ import (
 
 var _ signing.SignModeHandler = signModeDirectAuxHandler{}
 
+// NewSignModeDirectAuxHandler creates a new Direct Aux SignModeHandler
+// instance.
+func NewSignModeDirectAuxHandler() signing.SignModeHandler {
+	return signModeDirectAuxHandler{}
+}
+
 // signModeDirectAuxHandler defines the SIGN_MODE_DIRECT_AUX SignModeHandler
 type signModeDirectAuxHandler struct{}
 

x/auth/tx/legacy_amino_json.go

@@ -14,6 +14,12 @@ const aminoNonCriticalFieldsError = "protobuf transaction contains unknown non-c
 
 var _ signing.SignModeHandler = signModeLegacyAminoJSONHandler{}
 
+// NewSignModeLegacyAminoJSONHandler creates a new legacy Amino SignModeHandler
+// instance.
+func NewSignModeLegacyAminoJSONHandler() signing.SignModeHandler {
+	return signModeLegacyAminoJSONHandler{}
+}
+
 // signModeLegacyAminoJSONHandler defines the SIGN_MODE_LEGACY_AMINO_JSON
 // SignModeHandler.
 type signModeLegacyAminoJSONHandler struct{}

x/auth/tx/mode_handler.go

@@ -26,11 +26,11 @@ func makeSignModeHandler(modes []signingtypes.SignMode) signing.SignModeHandler
 	for i, mode := range modes {
 		switch mode {
 		case signingtypes.SignMode_SIGN_MODE_DIRECT:
-			handlers[i] = signModeDirectHandler{}
+			handlers[i] = NewSignModeDirectHandler()
 		case signingtypes.SignMode_SIGN_MODE_LEGACY_AMINO_JSON:
-			handlers[i] = signModeLegacyAminoJSONHandler{}
+			handlers[i] = NewSignModeLegacyAminoJSONHandler()
 		case signingtypes.SignMode_SIGN_MODE_DIRECT_AUX:
-			handlers[i] = signModeDirectAuxHandler{}
+			handlers[i] = NewSignModeDirectAuxHandler()
 		default:
 			panic(fmt.Errorf("unsupported sign mode %+v", mode))
 		}