fix: remove stores from renamed/deleted store upgrades (#9409)

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## Description

<!-- Add a description of the changes that this PR introduces and the files that
are the most critical to review.
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- stores that were renamed are now properly deleted
- deleted/renamed and renamed stores are no longer added to `CommitInfo`
- deleted/renamed stores are now properly removed from rootmulti store's memory

ref: #7991 
closes: N/A

---

Before we can merge this PR, please make sure that all the following items have been
checked off. If any of the checklist items are not applicable, please leave them but
write a little note why.

- [x] Targeted PR against correct branch (see [CONTRIBUTING.md](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [x] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
- [x] Code follows the [module structure standards](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules/structure.md).
- [ ] Wrote unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] Updated relevant documentation (`docs/`) or specification (`x/<module>/spec/`)
- [ ] Added relevant `godoc` [comments](https://blog.golang.org/godoc-documenting-go-code).
- [ ] Added a relevant changelog entry to the `Unreleased` section in `CHANGELOG.md`
- [x] Re-reviewed `Files changed` in the Github PR explorer
- [x] Review `Codecov Report` in the comment section below once CI passes

store/rootmulti/store.go

@@ -54,6 +54,7 @@ type Store struct {
 	lazyLoading    bool
 	pruneHeights   []int64
 	initialVersion int64
+	removalMap     map[types.StoreKey]bool
 
 	traceWriter  io.Writer
 	traceContext types.TraceContext
@@ -81,6 +82,7 @@ func NewStore(db dbm.DB) *Store {
 		keysByName:   make(map[string]types.StoreKey),
 		pruneHeights: make([]int64, 0),
 		listeners:    make(map[types.StoreKey][]types.WriteListener),
+		removalMap:   make(map[types.StoreKey]bool),
 	}
 }
 
@@ -210,9 +212,10 @@ func (rs *Store) loadVersion(ver int64, upgrades *types.StoreUpgrades) error {
 			if err := deleteKVStore(store.(types.KVStore)); err != nil {
 				return errors.Wrapf(err, "failed to delete store %s", key.Name())
 			}
+			rs.removalMap[key] = true
 		} else if oldName := upgrades.RenamedFrom(key.Name()); oldName != "" {
 			// handle renames specially
-			// make an unregistered key to satify loadCommitStore params
+			// make an unregistered key to satisfy loadCommitStore params
 			oldKey := types.NewKVStoreKey(oldName)
 			oldParams := storeParams
 			oldParams.key = oldKey
@@ -227,6 +230,11 @@ func (rs *Store) loadVersion(ver int64, upgrades *types.StoreUpgrades) error {
 			if err := moveKVStoreData(oldStore.(types.KVStore), store.(types.KVStore)); err != nil {
 				return errors.Wrapf(err, "failed to move store %s -> %s", oldName, key.Name())
 			}
+
+			// add the old key so its deletion is committed
+			newStores[oldKey] = oldStore
+			// this will ensure it's not perpetually stored in commitInfo
+			rs.removalMap[oldKey] = true
 		}
 	}
 
@@ -361,8 +369,19 @@ func (rs *Store) Commit() types.CommitID {
 		previousHeight = rs.lastCommitInfo.GetVersion()
 		version = previousHeight + 1
 	}
+	rs.lastCommitInfo = commitStores(version, rs.stores, rs.removalMap)
 
-	rs.lastCommitInfo = commitStores(version, rs.stores)
+	// remove remnants of removed stores
+	for sk := range rs.removalMap {
+		if _, ok := rs.stores[sk]; ok {
+			delete(rs.stores, sk)
+			delete(rs.storesParams, sk)
+			delete(rs.keysByName, sk.Name())
+		}
+	}
+
+	// reset the removalMap
+	rs.removalMap = make(map[types.StoreKey]bool)
 
 	// Determine if pruneHeight height needs to be added to the list of heights to
 	// be pruned, where pruneHeight = (commitHeight - 1) - KeepRecent.
@@ -944,7 +963,7 @@ func getLatestVersion(db dbm.DB) int64 {
 }
 
 // Commits each store and returns a new commitInfo.
-func commitStores(version int64, storeMap map[types.StoreKey]types.CommitKVStore) *types.CommitInfo {
+func commitStores(version int64, storeMap map[types.StoreKey]types.CommitKVStore, removalMap map[types.StoreKey]bool) *types.CommitInfo {
 	storeInfos := make([]types.StoreInfo, 0, len(storeMap))
 
 	for key, store := range storeMap {
@@ -954,10 +973,12 @@ func commitStores(version int64, storeMap map[types.StoreKey]types.CommitKVStore
 			continue
 		}
 
-		si := types.StoreInfo{}
+		if !removalMap[key] {
-		si.Name = key.Name()
+			si := types.StoreInfo{}
-		si.CommitId = commitID
+			si.Name = key.Name()
-		storeInfos = append(storeInfos, si)
+			si.CommitId = commitID
+			storeInfos = append(storeInfos, si)
+		}
 	}
 
 	return &types.CommitInfo{

store/rootmulti/store_test.go

@@ -300,8 +300,8 @@ func TestMultistoreLoadWithUpgrade(t *testing.T) {
 	ci, err = getCommitInfo(db, 2)
 	require.NoError(t, err)
 	require.Equal(t, int64(2), ci.Version)
-	require.Equal(t, 4, len(ci.StoreInfos), ci.StoreInfos)
+	require.Equal(t, 3, len(ci.StoreInfos), ci.StoreInfos)
-	checkContains(t, ci.StoreInfos, []string{"store1", "restore2", "store3", "store4"})
+	checkContains(t, ci.StoreInfos, []string{"store1", "restore2", "store4"})
 }
 
 func TestParsePath(t *testing.T) {

x/upgrade/types/storeloader_test.go

@@ -90,6 +90,7 @@ func TestSetLoader(t *testing.T) {
 		loadStoreKey string
 	}{
 		"don't set loader": {
+			setLoader:    nil,
 			origStoreKey: "foo",
 			loadStoreKey: "foo",
 		},
@@ -145,9 +146,13 @@ func TestSetLoader(t *testing.T) {
 			res := app.Commit()
 			require.NotNil(t, res.Data)
 
+			// checking the case of the store being renamed
+			if tc.setLoader != nil {
+				checkStore(t, db, upgradeHeight, tc.origStoreKey, k, nil)
+			}
+
 			// check db is properly updated
 			checkStore(t, db, upgradeHeight, tc.loadStoreKey, k, v)
-			checkStore(t, db, upgradeHeight, tc.loadStoreKey, []byte("foo"), nil)
 		})
 	}
 }