storage/memory's UpdateMany should fail if versions are not higher

Signed-off-by: Ying Li <ying.li@docker.com>

server/storage/memory.go

@@ -66,7 +66,9 @@ func (st *MemStorage) UpdateCurrent(gun string, update MetaUpdate) error {
 // UpdateMany updates multiple TUF records
 func (st *MemStorage) UpdateMany(gun string, updates []MetaUpdate) error {
 	for _, u := range updates {
-		st.UpdateCurrent(gun, u)
+		if err := st.UpdateCurrent(gun, u); err != nil {
+			return err
+		}
 	}
 	return nil
 }

server/storage/memory_test.go

@@ -19,6 +19,28 @@ func TestUpdateCurrent(t *testing.T) {
 	require.Equal(t, []byte("test"), v.data, "Data was incorrect")
 }
 
+func TestUpdateMany(t *testing.T) {
+	s := NewMemStorage()
+	require.NoError(t, s.UpdateMany("gun", []MetaUpdate{
+		{"role1", 1, []byte("test1")},
+		{"role2", 1, []byte("test2")},
+	}))
+
+	_, d, err := s.GetCurrent("gun", "role1")
+	require.Nil(t, err, "Expected error to be nil")
+	require.Equal(t, []byte("test1"), d, "Data was incorrect")
+
+	_, d, err = s.GetCurrent("gun", "role2")
+	require.Nil(t, err, "Expected error to be nil")
+	require.Equal(t, []byte("test2"), d, "Data was incorrect")
+
+	// updating even one with an equal version fails
+	require.IsType(t, &ErrOldVersion{}, s.UpdateMany("gun", []MetaUpdate{
+		{"role1", 1, []byte("test1")},
+		{"role2", 2, []byte("test2")},
+	}))
+}
+
 func TestGetCurrent(t *testing.T) {
 	s := NewMemStorage()