Add simple iterator test - all asc/desc

go.mod

@@ -21,6 +21,7 @@ require (
 	github.com/spf13/viper v1.6.3
 	github.com/stretchr/testify v1.6.1
 	github.com/tendermint/go-amino v0.15.1
+	github.com/tendermint/iavl v0.14.0
 	github.com/tendermint/tendermint v0.33.6
 	github.com/tendermint/tm-db v0.5.1
 	go.etcd.io/bbolt v1.3.4 // indirect

x/wasm/internal/types/iavl_range_test.go

@@ -0,0 +1,59 @@
+package types
+
+import (
+	"github.com/cosmos/cosmos-sdk/store"
+	"github.com/cosmos/cosmos-sdk/store/iavl"
+	"github.com/magiconair/properties/assert"
+	"github.com/stretchr/testify/require"
+	iavl2 "github.com/tendermint/iavl"
+	dbm "github.com/tendermint/tm-db"
+	"testing"
+)
+
+// This is modeled close to
+// https://github.com/CosmWasm/cosmwasm-plus/blob/f97a7de44b6a930fd1d5179ee6f95b786a532f32/packages/storage-plus/src/prefix.rs#L183
+// and designed to ensure the IAVL store handles bounds the same way as the mock storage we use in Rust contract tests
+func TestIavlRangeBounds(t *testing.T) {
+	db := dbm.NewMemDB()
+	tree, err := iavl2.NewMutableTree(db, 50)
+	require.NoError(t, err)
+	store := iavl.UnsafeNewStore(tree)
+
+	expected := []KV{
+		{[]byte("bar"), []byte("1")},
+		{[]byte("ra"), []byte("2")},
+		{[]byte("zi"), []byte("3")},
+	}
+	reversed := []KV{
+		{[]byte("zi"), []byte("3")},
+		{[]byte("ra"), []byte("2")},
+		{[]byte("bar"), []byte("1")},
+	}
+
+	// set up test cases, like `ensure_proper_range_bounds` in `cw-storage-plus`
+	for _, kv := range expected {
+		store.Set(kv.Key, kv.Value)
+	}
+
+	ascAll := store.Iterator(nil, nil)
+	assert.Equal(t, expected, consume(ascAll))
+
+	descAll := store.ReverseIterator(nil, nil)
+	assert.Equal(t, reversed, consume(descAll))
+}
+
+type KV struct {
+	Key []byte
+	Value []byte
+}
+
+func consume(itr store.Iterator) []KV {
+	defer itr.Close()
+
+	var res []KV
+	for ; itr.Valid(); itr.Next() {
+		k, v := itr.Key(), itr.Value()
+		res = append(res, KV{k, v})
+	}
+	return res
+}