From eb80a1a141c92fcaccd712d90bff59e30bb238a9 Mon Sep 17 00:00:00 2001
From: Matt Kocubinski <mkocubinski@gmail.com>
Date: Mon, 24 Apr 2023 20:50:42 -0500
Subject: [PATCH] feat(x/tx): API improvements (#15871)

---
 x/tx/signing/handler_map.go      | 19 ++++++++++--
 x/tx/signing/handler_map_test.go | 50 ++++++++++++++++++++++++++++++++
 x/tx/signing/textual/handler.go  | 10 ++++---
 3 files changed, 73 insertions(+), 6 deletions(-)
 create mode 100644 x/tx/signing/handler_map_test.go

diff --git a/x/tx/signing/handler_map.go b/x/tx/signing/handler_map.go
index 076a2166892c0..98238a51d047f 100644
--- a/x/tx/signing/handler_map.go
+++ b/x/tx/signing/handler_map.go
@@ -11,17 +11,27 @@ import (
 // based on sign mode.
 type HandlerMap struct {
 	signModeHandlers map[signingv1beta1.SignMode]SignModeHandler
+	defaultMode      signingv1beta1.SignMode
 	modes            []signingv1beta1.SignMode
 }
 
-// NewHandlerMap constructs a new sign mode handler map.
+// NewHandlerMap constructs a new sign mode handler map. The first handler is used as the default.
 func NewHandlerMap(handlers ...SignModeHandler) *HandlerMap {
+	if len(handlers) == 0 {
+		panic("no handlers")
+	}
 	res := &HandlerMap{
 		signModeHandlers: map[signingv1beta1.SignMode]SignModeHandler{},
 	}
 
-	for _, handler := range handlers {
+	for i, handler := range handlers {
+		if handler == nil {
+			panic("nil handler")
+		}
 		mode := handler.Mode()
+		if i == 0 {
+			res.defaultMode = mode
+		}
 		res.signModeHandlers[mode] = handler
 		res.modes = append(res.modes, mode)
 	}
@@ -34,6 +44,11 @@ func (h *HandlerMap) SupportedModes() []signingv1beta1.SignMode {
 	return h.modes
 }
 
+// DefaultMode returns the default mode for this handler map.
+func (h *HandlerMap) DefaultMode() signingv1beta1.SignMode {
+	return h.defaultMode
+}
+
 // GetSignBytes returns the sign bytes for the transaction for the requested mode.
 func (h *HandlerMap) GetSignBytes(ctx context.Context, signMode signingv1beta1.SignMode, signerData SignerData, txData TxData) ([]byte, error) {
 	handler, ok := h.signModeHandlers[signMode]
diff --git a/x/tx/signing/handler_map_test.go b/x/tx/signing/handler_map_test.go
new file mode 100644
index 0000000000000..a937ac643ee04
--- /dev/null
+++ b/x/tx/signing/handler_map_test.go
@@ -0,0 +1,50 @@
+package signing_test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	signingv1beta1 "cosmossdk.io/api/cosmos/tx/signing/v1beta1"
+	"cosmossdk.io/x/tx/signing"
+)
+
+var (
+	_ signing.SignModeHandler = directHandler{}
+	_ signing.SignModeHandler = aminoJSONHandler{}
+)
+
+type directHandler struct{}
+
+func (s directHandler) Mode() signingv1beta1.SignMode {
+	return signingv1beta1.SignMode_SIGN_MODE_DIRECT
+}
+
+func (s directHandler) GetSignBytes(_ context.Context, _ signing.SignerData, _ signing.TxData) ([]byte, error) {
+	panic("not implemented")
+}
+
+type aminoJSONHandler struct{}
+
+func (s aminoJSONHandler) Mode() signingv1beta1.SignMode {
+	return signingv1beta1.SignMode_SIGN_MODE_LEGACY_AMINO_JSON
+}
+
+func (s aminoJSONHandler) GetSignBytes(_ context.Context, _ signing.SignerData, _ signing.TxData) ([]byte, error) {
+	panic("not implemented")
+}
+
+func TestNewHandlerMap(t *testing.T) {
+	require.PanicsWithValue(t, "nil handler", func() {
+		signing.NewHandlerMap(nil)
+	})
+	require.PanicsWithValue(t, "no handlers", func() {
+		signing.NewHandlerMap()
+	})
+	dh := directHandler{}
+	ah := aminoJSONHandler{}
+	handlerMap := signing.NewHandlerMap(dh, aminoJSONHandler{})
+	require.Equal(t, dh.Mode(), handlerMap.DefaultMode())
+	require.NotEqual(t, ah.Mode(), handlerMap.DefaultMode())
+}
diff --git a/x/tx/signing/textual/handler.go b/x/tx/signing/textual/handler.go
index a6e8d12d02443..97b6e3a752df0 100644
--- a/x/tx/signing/textual/handler.go
+++ b/x/tx/signing/textual/handler.go
@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"reflect"
 
-	signingv1beta1 "cosmossdk.io/api/cosmos/tx/signing/v1beta1"
 	"google.golang.org/protobuf/proto"
 	"google.golang.org/protobuf/reflect/protoreflect"
 	"google.golang.org/protobuf/reflect/protoregistry"
@@ -14,9 +13,12 @@ import (
 	"google.golang.org/protobuf/types/known/durationpb"
 	"google.golang.org/protobuf/types/known/timestamppb"
 
+	signingv1beta1 "cosmossdk.io/api/cosmos/tx/signing/v1beta1"
+
+	cosmos_proto "github.com/cosmos/cosmos-proto"
+
 	bankv1beta1 "cosmossdk.io/api/cosmos/bank/v1beta1"
 	basev1beta1 "cosmossdk.io/api/cosmos/base/v1beta1"
-	cosmos_proto "github.com/cosmos/cosmos-proto"
 
 	"cosmossdk.io/x/tx/signing"
 	"cosmossdk.io/x/tx/signing/textual/internal/textualpb"
@@ -41,7 +43,7 @@ type SignModeOptions struct {
 
 	// FileResolver are the protobuf files to use for resolving message
 	// descriptors. If it is nil, the global protobuf registry will be used.
-	FileResolver *protoregistry.Files
+	FileResolver signing.ProtoFileResolver
 
 	// TypeResolver are the protobuf type resolvers to use for resolving message
 	// types. If it is nil, then a dynamicpb will be used on top of FileResolver.
@@ -51,7 +53,7 @@ type SignModeOptions struct {
 // SignModeHandler holds the configuration for dispatching
 // to specific value renderers for SIGN_MODE_TEXTUAL.
 type SignModeHandler struct {
-	fileResolver        *protoregistry.Files
+	fileResolver        signing.ProtoFileResolver
 	typeResolver        protoregistry.MessageTypeResolver
 	coinMetadataQuerier CoinMetadataQueryFn
 	// scalars defines a registry for Cosmos scalars.