@Test
    public void testAssignFieldPathUpdate() {
        roundtripSerializeJsonAndMatch(inputJson(
                "{",
                "   'update': 'DOCUMENT_ID',",
                "   'fields': {",
                "       'deep_map{my_field}': {",
                "           'assign': {",
                "               'my_key': 'my value',",
                "               'new_key': 'new value'",
                "           }",
                "       },",
                "       'map_struct{my_key}': {",
                "           'assign': {",
                "               'my_string_field': 'Some string',",
                "               'my_int_field': 5",
                "           }",
                "       },",
                "       'map_struct{my_key}.my_int_field': {",
                "           'assign': 10",
                "       }",
                "   }",
                "}"
        ));
    }
Tests roundtrip serialization (JSON -> DocumentUpdate -> Buffer -> DocumentUpdate -> JSON) of document updates.

@author Vegard Sjonfjell
document/src/test/java/com/yahoo/document/json/DocumentUpdateJsonSerializerTest.java