@Test
    public void testCreateIfNotExistFalse() {
        // NOTE: DocumentUpdateJsonSerializer only writes 'create' when true.
        roundtripSerializeJsonAndMatch(inputJson(
                "{",
                "    'update': 'DOCUMENT_ID',",
                "    'create': false,",
                "    'fields': {",
                "        'int_field': {",
                "            'assign': 42",
                "        }",
                "    }",
                "}"
        ), inputJson("{",
                "    'update': 'DOCUMENT_ID',",
                "    'fields': {",
                "        'int_field': {",
                "            'assign': 42",
                "        }",
                "    }",
                "}"));
    }
Tests roundtrip serialization (JSON -> DocumentUpdate -> Buffer -> DocumentUpdate -> JSON) of document updates.

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