fix(gov): Fix v3 votes migrations (#14214)

Co-authored-by: Julien Robert <julien@rbrt.fr>
Co-authored-by: atheeshp <59333759+atheeshp@users.noreply.github.com>
Co-authored-by: Aleksandr Bezobchuk <alexanderbez@users.noreply.github.com>

CHANGELOG.md

@@ -105,6 +105,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### State Machine Breaking
 
+* (x/gov) [#14214](https://github.com/cosmos/cosmos-sdk/pull/14214) Fix gov v0.46 migration to v1 votes.
 * (x/group) [#13742](https://github.com/cosmos/cosmos-sdk/pull/13742) Migrate group policy account from module accounts to base account.
 * (x/group) [#14071](https://github.com/cosmos/cosmos-sdk/pull/14071) Don't re-tally proposal after voting period end if they have been marked as ACCEPTED or REJECTED.
 * (codec) [#13307](https://github.com/cosmos/cosmos-sdk/pull/13307) Register all modules' `Msg`s with group's ModuleCdc so that Amino sign bytes are correctly generated.

x/gov/migrations/v3/json_test.go

@@ -20,6 +20,8 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/gov/types/v1beta1"
 )
 
+var voter = sdk.MustAccAddressFromBech32("cosmos1fl48vsnmsdzcv85q5d2q4z5ajdha8yu34mf0eh")
+
 func TestMigrateJSON(t *testing.T) {
 	encodingConfig := moduletestutil.MakeTestEncodingConfig(gov.AppModuleBasic{})
 	clientCtx := client.Context{}.
@@ -27,9 +29,6 @@ func TestMigrateJSON(t *testing.T) {
 		WithTxConfig(encodingConfig.TxConfig).
 		WithCodec(encodingConfig.Codec)
 
-	voter, err := sdk.AccAddressFromBech32("cosmos1fl48vsnmsdzcv85q5d2q4z5ajdha8yu34mf0eh")
-	require.NoError(t, err)
-
 	govGenState := v1beta1.DefaultGenesisState()
 	propTime := time.Unix(1e9, 0)
 	contentAny, err := codectypes.NewAnyWithValue(v1beta1.NewTextProposal("my title", "my desc").(proto.Message))

x/gov/migrations/v3/store.go

@@ -6,7 +6,8 @@ import (
 	storetypes "github.com/cosmos/cosmos-sdk/store/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	v1 "github.com/cosmos/cosmos-sdk/x/gov/migrations/v1"
-	"github.com/cosmos/cosmos-sdk/x/gov/types/v1beta1"
+	govv1 "github.com/cosmos/cosmos-sdk/x/gov/types/v1"
+	govv1beta1 "github.com/cosmos/cosmos-sdk/x/gov/types/v1beta1"
 )
 
 // migrateProposals migrates all legacy proposals into MsgExecLegacyContent
@@ -18,7 +19,7 @@ func migrateProposals(store sdk.KVStore, cdc codec.BinaryCodec) error {
 	defer iter.Close()
 
 	for ; iter.Valid(); iter.Next() {
-		var oldProp v1beta1.Proposal
+		var oldProp govv1beta1.Proposal
 		err := cdc.Unmarshal(iter.Value(), &oldProp)
 		if err != nil {
 			return err
@@ -40,6 +41,45 @@ func migrateProposals(store sdk.KVStore, cdc codec.BinaryCodec) error {
 	return nil
 }
 
+// migrateVotes migrates all v1beta1 weighted votes (with sdk.Dec as weight)
+// to v1 weighted votes (with string as weight)
+func migrateVotes(store sdk.KVStore, cdc codec.BinaryCodec) error {
+	votesStore := prefix.NewStore(store, v1.VotesKeyPrefix)
+
+	iter := votesStore.Iterator(nil, nil)
+	defer iter.Close()
+
+	for ; iter.Valid(); iter.Next() {
+		var oldVote govv1beta1.Vote
+		err := cdc.Unmarshal(iter.Value(), &oldVote)
+		if err != nil {
+			return err
+		}
+
+		newVote := govv1.Vote{
+			ProposalId: oldVote.ProposalId,
+			Voter:      oldVote.Voter,
+		}
+		newOptions := make([]*govv1.WeightedVoteOption, len(oldVote.Options))
+		for i, o := range oldVote.Options {
+			newOptions[i] = &govv1.WeightedVoteOption{
+				Option: govv1.VoteOption(o.Option),
+				Weight: o.Weight.String(), // Convert to decimal string
+			}
+		}
+		newVote.Options = newOptions
+		bz, err := cdc.Marshal(&newVote)
+		if err != nil {
+			return err
+		}
+
+		// Set new value on store.
+		votesStore.Set(iter.Key(), bz)
+	}
+
+	return nil
+}
+
 // MigrateStore performs in-place store migrations from v2 (v0.43) to v3 (v0.46). The
 // migration includes:
 //
@@ -47,5 +87,9 @@ func migrateProposals(store sdk.KVStore, cdc codec.BinaryCodec) error {
 func MigrateStore(ctx sdk.Context, storeKey storetypes.StoreKey, cdc codec.BinaryCodec) error {
 	store := ctx.KVStore(storeKey)
 
+	if err := migrateVotes(store, cdc); err != nil {
+		return err
+	}
+
 	return migrateProposals(store, cdc)
 }

x/gov/migrations/v3/store_test.go

@@ -41,6 +41,15 @@ func TestMigrateStore(t *testing.T) {
 	store.Set(v1gov.ProposalKey(prop1.ProposalId), prop1Bz)
 	store.Set(v1gov.ProposalKey(prop2.ProposalId), prop2Bz)
 
+	// Vote on prop 1
+	options := []v1beta1.WeightedVoteOption{
+		{Option: v1beta1.OptionNo, Weight: sdk.MustNewDecFromStr("0.3")},
+		{Option: v1beta1.OptionYes, Weight: sdk.MustNewDecFromStr("0.7")},
+	}
+	vote1 := v1beta1.NewVote(1, voter, options)
+	vote1Bz := cdc.MustMarshal(&vote1)
+	store.Set(v1gov.VoteKey(1, voter), vote1Bz)
+
 	// Run migrations.
 	err = v3gov.MigrateStore(ctx, govKey, cdc)
 	require.NoError(t, err)
@@ -54,6 +63,14 @@ func TestMigrateStore(t *testing.T) {
 	err = cdc.Unmarshal(store.Get(v1gov.ProposalKey(prop2.ProposalId)), &newProp2)
 	require.NoError(t, err)
 	compareProps(t, prop2, newProp2)
+
+	var newVote1 v1.Vote
+	err = cdc.Unmarshal(store.Get(v1gov.VoteKey(prop1.ProposalId, voter)), &newVote1)
+	require.NoError(t, err)
+	// Without the votes migration, we would have 300000000000000000 in state,
+	// because of how sdk.Dec stores itself in state.
+	require.Equal(t, "0.300000000000000000", newVote1.Options[0].Weight)
+	require.Equal(t, "0.700000000000000000", newVote1.Options[1].Weight)
 }
 
 func compareProps(t *testing.T, oldProp v1beta1.Proposal, newProp v1.Proposal) {