from bonobo.constants import NOT_MODIFIED
from bonobo.util.testing import BufferingNodeExecutionContext


def useless(*args, **kwargs):
    return NOT_MODIFIED


def test_not_modified():
    input_messages = [
        ('foo', 'bar'),
        ('foo', 'baz'),
    ]

    with BufferingNodeExecutionContext(useless) as context:
        context.write_sync(*input_messages)

    assert context.get_buffer() == input_messages