@Test
    public void tensor_modify_update_on_non_tensor_field_throws() {
        try {
            JsonReader reader = createReader("""
                                             {
                                               "update": "id:unittest:smoke::doc1",
                                               "fields": {
                                                 "something": {
                                                   "modify": {}
                                                 }
                                               }
                                             }
                                             """);
            reader.readSingleDocument(DocumentOperationType.UPDATE, "id:unittest:smoke::doc1");
            fail("Expected exception");
        }
        catch (IllegalArgumentException e) {
            assertEquals("Error in 'something': A modify update can only be applied to tensor fields. Field 'something' is of type 'string'",
                         Exceptions.toMessageString(e));
        }
    }
Tests parsing of various tensor values set at the root, i.e. no 'cells', 'blocks' or 'values'
document/src/test/java/com/yahoo/document/json/JsonReaderTestCase.java