fix: add old supply offset functions

CHANGELOG.md

@@ -64,6 +64,9 @@ This v0.50.x branch was created at the [bd886bb4b03fdfc52bdc1fa2f98e960316604f89
 
 ### Osmosis Specific PRs (should not upstream)
 
+* Fix Supply Offsets
+    * [#629](https://github.com/osmosis-labs/cosmos-sdk/pull/629) fix: add old supply offset functions
+
 * Slashing
     * [0609929](https://github.com/osmosis-labs/cosmos-sdk/commit/0609929d2ddfd845aebfe53622176660f8392fcb) Osmosis specific key migration slashing changes, due to implementing it early in v0.47.x
 

x/bank/keeper/supply_offset_old.go

@@ -0,0 +1,69 @@
+package keeper
+
+import (
+	"context"
+	"fmt"
+
+	"cosmossdk.io/math"
+	"cosmossdk.io/store/prefix"
+
+	"github.com/cosmos/cosmos-sdk/runtime"
+	"github.com/cosmos/cosmos-sdk/x/bank/types"
+)
+
+// NOTE: All these functions should only be used in the v27 migration
+// this file should be removed completely after the migration
+
+// GetSupplyOffset retrieves the SupplyOffset from store for a specific denom using the pre v26 (old) key
+// TODO: Remove after v27 migration
+func (k BaseViewKeeper) GetSupplyOffsetOld(ctx context.Context, denom string) math.Int {
+	store := runtime.KVStoreAdapter(k.storeService.OpenKVStore(ctx))
+	supplyOffsetStore := prefix.NewStore(store, types.SupplyOffsetKeyOld)
+
+	bz := supplyOffsetStore.Get([]byte(denom))
+	if bz == nil {
+		return math.NewInt(0)
+	}
+
+	var amount math.Int
+	err := amount.Unmarshal(bz)
+	if err != nil {
+		panic(fmt.Errorf("unable to unmarshal supply offset value %v", err))
+	}
+
+	return amount
+}
+
+// RemoveOldSupplyOffset removes the old supply offset key
+// TODO: Remove after v27 migration
+func (k BaseViewKeeper) RemoveOldSupplyOffset(ctx context.Context, denom string) {
+	store := runtime.KVStoreAdapter(k.storeService.OpenKVStore(ctx))
+	supplyOffsetStore := prefix.NewStore(store, types.SupplyOffsetKeyOld)
+
+	supplyOffsetStore.Delete([]byte(denom))
+}
+
+// setSupplyOffsetOld sets the supply offset for the given denom using the pre v26 (old) key
+// TODO: Remove after v27 migration
+func (k BaseKeeper) setSupplyOffsetOld(ctx context.Context, denom string, offsetAmount math.Int) {
+	intBytes, err := offsetAmount.Marshal()
+	if err != nil {
+		panic(fmt.Errorf("unable to marshal amount value %v", err))
+	}
+
+	store := runtime.KVStoreAdapter(k.storeService.OpenKVStore(ctx))
+	supplyOffsetStore := prefix.NewStore(store, types.SupplyOffsetKeyOld)
+
+	// Bank invariants and IBC requires to remove zero coins.
+	if offsetAmount.IsZero() {
+		supplyOffsetStore.Delete([]byte(denom))
+	} else {
+		supplyOffsetStore.Set([]byte(denom), intBytes)
+	}
+}
+
+// AddSupplyOffsetOld adjusts the current supply offset of a denom by the inputted offsetAmount using the pre v26 (old) key
+// TODO: Remove after v27 migration
+func (k BaseKeeper) AddSupplyOffsetOld(ctx context.Context, denom string, offsetAmount math.Int) {
+	k.setSupplyOffsetOld(ctx, denom, k.GetSupplyOffsetOld(ctx, denom).Add(offsetAmount))
+}

x/bank/types/keys.go

@@ -33,7 +33,12 @@ var (
 	// ParamsKey is the prefix for x/bank parameters
 	ParamsKey = collections.NewPrefix(5)
 
+	// SupplyOffKey is a Osmosis specific key that handles supply offsets
 	SupplyOffsetKey = collections.NewPrefix(88)
+
+	// SupplyOffKeyOld is a Osmosis specific key that handles supply offsets pre v0.50
+	// TODO: Remove in the v28 upgrade
+	SupplyOffsetKeyOld = []byte{0x88}
 )
 
 // BalanceValueCodec is a codec for encoding bank balances in a backwards compatible way.