GasKVStore WIP

store/gaskvstore.go

@@ -0,0 +1,80 @@
+package store
+
+import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
+
+// gasKVStore applies gas tracking to an underlying kvstore
+type gasKVStore struct {
+	gasMeter sdk.GasMeter
+	parent   KVStore
+}
+
+// nolint
+func NewGasKVStore(gasMeter sdk.GasMeter, parent KVStore) *gasKVStore {
+	kvs := &gasKVStore{
+		gasMeter: gasMeter,
+		parent:   parent,
+	}
+	return kvs
+}
+
+// Implements Store.
+func (gi *gasKVStore) GetStoreType() StoreType {
+	return gi.parent.GetStoreType()
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) Get(key []byte) (value []byte) {
+	return gi.parent.Get(key)
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) Set(key []byte, value []byte) {
+	gi.parent.Set(key, value)
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) Has(key []byte) bool {
+	return gi.parent.Has(key)
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) Delete(key []byte) {
+	gi.parent.Delete(key)
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) Iterator(start, end []byte) Iterator {
+	return gi.iterator(start, end, true)
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) ReverseIterator(start, end []byte) Iterator {
+	return gi.iterator(start, end, false)
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) SubspaceIterator(prefix []byte) Iterator {
+	return gi.iterator(prefix, sdk.PrefixEndBytes(prefix), true)
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) ReverseSubspaceIterator(prefix []byte) Iterator {
+	return gi.iterator(prefix, sdk.PrefixEndBytes(prefix), false)
+}
+
+// Implements KVStore.
+func (gi *gasKVStore) CacheWrap() CacheWrap {
+	return gi.parent.CacheWrap() // TODO
+}
+
+func (gi *gasKVStore) iterator(start, end []byte, ascending bool) Iterator {
+	var parent Iterator
+	if ascending {
+		parent = gi.parent.Iterator(start, end)
+	} else {
+		parent = gi.parent.ReverseIterator(start, end)
+	}
+	return parent // TODO
+}

store/gaskvstore_test.go

@@ -0,0 +1,27 @@
+package store
+
+import (
+	"testing"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/stretchr/testify/require"
+	dbm "github.com/tendermint/tmlibs/db"
+)
+
+func newGasKVStore() KVStore {
+	meter := sdk.NewGasMeter(1000)
+	mem := dbStoreAdapter{dbm.NewMemDB()}
+	return NewGasKVStore(meter, mem)
+}
+
+func TestGasKVStore(t *testing.T) {
+	mem := dbStoreAdapter{dbm.NewMemDB()}
+	meter := sdk.NewGasMeter(1000)
+	st := NewGasKVStore(meter, mem)
+
+	require.Empty(t, st.Get(keyFmt(1)), "Expected `key1` to be empty")
+
+	mem.Set(keyFmt(1), valFmt(1))
+	st.Set(keyFmt(1), valFmt(1))
+	require.Equal(t, valFmt(1), st.Get(keyFmt(1)))
+}