@Test
    public void testAssignTensor() {
        roundtripSerializeJsonAndMatch(inputJson(
                "{",
                "    'update': 'DOCUMENT_ID',",
                "    'fields': {",
                "        'sparse_tensor': {",
                "            'assign': {",
                "                'type': 'tensor(x{},y{})',",
                "                'cells': [",
                "                    { 'address': { 'x': 'a', 'y': 'b' }, 'value': 2.0 },",
                "                    { 'address': { 'x': 'c', 'y': 'b' }, 'value': 3.0 }",
                "                ]",
                "            }",
                "        }",
                "    }",
                "}"
        ));
    }
Tests roundtrip serialization (JSON -> DocumentUpdate -> Buffer -> DocumentUpdate -> JSON) of document updates.

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