fix: working hash with initial version (cosmos#943)

mutable_tree.go

@@ -140,7 +140,7 @@ func (tree *MutableTree) Hash() []byte {
 
 // WorkingHash returns the hash of the current working tree.
 func (tree *MutableTree) WorkingHash() []byte {
-	return tree.ImmutableTree.Hash()
+	return tree.root.hashWithCount(tree.WorkingVersion())
 }
 
 func (tree *MutableTree) WorkingVersion() int64 {

tree_test.go

@@ -1920,3 +1920,37 @@ func TestReferenceRoot(t *testing.T) {
 	_, err = tree.Set([]byte("key1"), []byte("value2"))
 	require.NoError(t, err)
 }
+
+func TestWorkingHashWithInitialVersion(t *testing.T) {
+	db, err := dbm.NewDB("test", "memdb", "")
+	require.NoError(t, err)
+	defer db.Close()
+
+	initialVersion := int64(100)
+	tree := NewMutableTree(db, 0, false, log.NewNopLogger())
+	tree.SetInitialVersion(uint64(initialVersion))
+
+	v := tree.WorkingVersion()
+	require.Equal(t, initialVersion, v)
+
+	_, err = tree.Set([]byte("key1"), []byte("value1"))
+	require.NoError(t, err)
+
+	workingHash := tree.WorkingHash()
+	commitHash, _, err := tree.SaveVersion()
+	require.NoError(t, err)
+	require.Equal(t, commitHash, workingHash)
+
+	db, err = dbm.NewDB("test", "memdb", "")
+	require.NoError(t, err)
+
+	// without WorkingHash
+	tree = NewMutableTree(db, 0, false, log.NewNopLogger(), InitialVersionOption(uint64(initialVersion)))
+
+	_, err = tree.Set([]byte("key1"), []byte("value1"))
+	require.NoError(t, err)
+
+	commitHash1, _, err := tree.SaveVersion()
+	require.NoError(t, err)
+	require.Equal(t, commitHash1, commitHash)
+}