diff --git a/tests/test_dynamodb2/test_dynamodb.py b/tests/test_dynamodb2/test_dynamodb.py index 180f460c..d36fdc7f 100644 --- a/tests/test_dynamodb2/test_dynamodb.py +++ b/tests/test_dynamodb2/test_dynamodb.py @@ -3634,6 +3634,31 @@ def test_update_supports_list_append_with_nested_if_not_exists_operation(): ) +@mock_dynamodb2 +def test_update_supports_list_append_with_nested_if_not_exists_operation_and_property_already_exists(): + dynamo = boto3.resource("dynamodb", region_name="us-west-1") + table_name = "test" + + dynamo.create_table( + TableName=table_name, + AttributeDefinitions=[{"AttributeName": "Id", "AttributeType": "S"}], + KeySchema=[{"AttributeName": "Id", "KeyType": "HASH"}], + ProvisionedThroughput={"ReadCapacityUnits": 20, "WriteCapacityUnits": 20}, + ) + + table = dynamo.Table(table_name) + + table.put_item(Item={"Id": "item-id", "event_history":["other_value"]}) + table.update_item( + Key={"Id": "item-id"}, + UpdateExpression="SET event_history = list_append(if_not_exists(event_history, :empty_list), :new_value)", + ExpressionAttributeValues={":empty_list": [], ":new_value": ["some_value"]}, + ) + table.get_item(Key={"Id": "item-id"})["Item"].should.equal( + {"Id": "item-id", "event_history": ["other_value", "some_value"]} + ) + + @mock_dynamodb2 def test_update_catches_invalid_list_append_operation(): client = boto3.client("dynamodb", region_name="us-east-1")