feat(core/coretesting): make memDB satisfy db.Db interface

core/testing/memdb.go

@@ -258,7 +258,9 @@ func (mi *memIterator) assertValid() {
 	}
 }
 
-var _ store.KVStoreWithBatch = (*MemDB)(nil)
+var (
+	_ store.KVStoreWithBatch = (*MemDB)(nil)
+)
 
 // MemDB is a simple in-memory key-value store with Batch support.
 type MemDB struct {
@@ -291,12 +293,20 @@ func (bt *MemDB) Set(key, value []byte) error {
 	return bt.kv.Set(key, value)
 }
 
+func (bt *MemDB) SetSync(key, value []byte) error {
+	return bt.Set(key, value)
+}
+
 func (bt *MemDB) Delete(key []byte) error {
 	bt.mtx.Lock()
 	defer bt.mtx.Unlock()
 	return bt.kv.Delete(key)
 }
 
+func (bt *MemDB) DeleteSync(key []byte) error {
+	return bt.Delete(key)
+}
+
 func (bt *MemDB) Iterator(start, end []byte) (store.Iterator, error) {
 	return bt.kv.Iterator(start, end)
 }
@@ -305,6 +315,27 @@ func (bt *MemDB) ReverseIterator(start, end []byte) (store.Iterator, error) {
 	return bt.kv.ReverseIterator(start, end)
 }
 
+func (db *MemDB) Print() error {
+	db.mtx.RLock()
+	defer db.mtx.RUnlock()
+
+	db.kv.tree.Ascend(item{}, func(i item) bool {
+		fmt.Printf("[%X]:\t[%X]\n", i.key, i.value)
+		return true
+	})
+	return nil
+}
+
+func (db *MemDB) Stats() map[string]string {
+	db.mtx.RLock()
+	defer db.mtx.RUnlock()
+
+	stats := make(map[string]string)
+	stats["database.type"] = "memDB"
+	stats["database.size"] = fmt.Sprintf("%d", db.kv.tree.Len())
+	return stats
+}
+
 // Close closes the MemDB, releasing any resources held.
 func (db *MemDB) Close() error {
 	return nil

tests/integration/type_check.go

@@ -0,0 +1,14 @@
+package integration
+
+import (
+	coretesting "cosmossdk.io/core/testing"
+
+	db "github.com/cosmos/cosmos-db"
+)
+
+// This file contains a list of type checks that are used to ensure that implementations
+// matches the interface. We do not do those type checks directly in the components to
+// avoid to bring in more dependencies than needed.
+var (
+	_ db.DB = (*coretesting.MemDB)(nil)
+)