Merge branch 'juerg/cachedfail' into 'master'

@pytest.mark.datafiles(DATA_DIR)

@pytest.mark.parametrize("on_error", ("continue", "quit"))

def test_push_cached_fail(cli, tmpdir, datafiles, on_error):

    if on_error == 'quit':

        pytest.xfail('https://gitlab.com/BuildStream/buildstream/issues/534')

    project = os.path.join(datafiles.dirname, datafiles.basename)

    element_path = os.path.join(project, 'elements', 'element.bst')

    workspace = os.path.join(cli.directory, 'workspace')

    checkout = os.path.join(cli.directory, 'checkout')

    # Write out our test target

    element = {

        'config': {

            'commands': [

                'false',

                # Ensure unique cache key for different test variants

                'TEST="{}"'.format(os.environ.get('PYTEST_CURRENT_TEST')),

            ],

        },

    }