fix: bank store migration (backport #13821) (#13829)

* fix: bank store migration (#13821)

(cherry picked from commit d314a12)

# Conflicts:
#	x/bank/migrations/v3/store.go
#	x/bank/migrations/v3/store_test.go

* updates

Co-authored-by: billy rennekamp <billy.rennekamp@gmail.com>
Co-authored-by: Julien Robert <julien@rbrt.fr>

CHANGELOG.md

@@ -43,6 +43,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Bug Fixes
 
+* (x/bank) [#13821](https://github.com/cosmos/cosmos-sdk/pull/13821) Fix bank store migration of coin metadata.
 * (x/group) [#13808](https://github.com/cosmos/cosmos-sdk/pull/13808) Fix propagation of message events to the current context in `EndBlocker`.
 * (x/gov) [#13728](https://github.com/cosmos/cosmos-sdk/pull/13728) Fix propagation of message events to the current context in `EndBlocker`.
 * (store) [#13803](https://github.com/cosmos/cosmos-sdk/pull/13803) Add an error log if iavl set operation failed.

x/bank/migrations/v046/store.go

@@ -80,7 +80,7 @@ func migrateDenomMetadata(store sdk.KVStore) error {
 
 	for ; oldDenomMetaDataIter.Valid(); oldDenomMetaDataIter.Next() {
 		oldKey := oldDenomMetaDataIter.Key()
-		l := len(oldKey)/2 + 1
+		l := len(oldKey) / 2
 
 		newKey := make([]byte, len(types.DenomMetadataPrefix)+l)
 		// old key: prefix_bytes | denom_bytes | denom_bytes

x/bank/migrations/v046/store_test.go

@@ -87,8 +87,8 @@ func TestMigrateDenomMetaData(t *testing.T) {
 	denomMetadataStore := prefix.NewStore(store, v043.DenomMetadataPrefix)
 
 	for i := range []int{0, 1} {
-		key := append(v043.DenomMetadataPrefix, []byte(metaData[i].Base)...)
 		// keys before 0.45 had denom two times in the key
+		key := append([]byte{}, []byte(metaData[i].Base)...)
 		key = append(key, []byte(metaData[i].Base)...)
 		bz, err := encCfg.Codec.Marshal(&metaData[i])
 		require.NoError(t, err)
@@ -105,11 +105,11 @@ func TestMigrateDenomMetaData(t *testing.T) {
 		newKey := denomMetadataIter.Key()
 
 		// make sure old entry is deleted
-		oldKey := append(newKey, newKey[1:]...)
+		oldKey := append(newKey, newKey[0:]...)
 		bz := denomMetadataStore.Get(oldKey)
 		require.Nil(t, bz)
 
-		require.Equal(t, string(newKey)[1:], metaData[i].Base, "idx: %d", i)
+		require.Equal(t, string(newKey), metaData[i].Base, "idx: %d", i)
 		bz = denomMetadataStore.Get(denomMetadataIter.Key())
 		require.NotNil(t, bz)
 		err := encCfg.Codec.Unmarshal(bz, &result)