How to use the tmuxp.config.trickle function in tmuxp

def test_in_session_scope():
    sconfig = load_yaml(fixtures.shell_command_before_session.before)

    config.validate_schema(sconfig)

    assert config.expand(sconfig) == sconfig
    assert config.expand(config.trickle(sconfig)) == load_yaml(
        fixtures.shell_command_before_session.expected
    )

def test_before_load_true_if_test_passes_with_args(server):
    config_script_completes = loadfixture(
        "workspacebuilder/config_script_completes.yaml"
    )

    assert os.path.exists(os.path.join(fixtures_dir, 'script_complete.sh'))
    sconfig = kaptan.Kaptan(handler='yaml')
    yaml = config_script_completes.format(
        fixtures_dir=fixtures_dir,
        script_complete=os.path.join(fixtures_dir, 'script_complete.sh') + ' -v',
    )

    sconfig = sconfig.import_config(yaml).get()
    sconfig = config.expand(sconfig)
    sconfig = config.trickle(sconfig)

    builder = WorkspaceBuilder(sconf=sconfig)

    with temp_session(server) as session:
        builder.build(session=session)

def test_before_load_true_if_test_passes(server):
    config_script_completes = loadfixture(
        "workspacebuilder/config_script_completes.yaml"
    )
    assert os.path.exists(os.path.join(fixtures_dir, 'script_complete.sh'))
    sconfig = kaptan.Kaptan(handler='yaml')
    yaml = config_script_completes.format(
        fixtures_dir=fixtures_dir,
        script_complete=os.path.join(fixtures_dir, 'script_complete.sh'),
    )

    sconfig = sconfig.import_config(yaml).get()
    sconfig = config.expand(sconfig)
    sconfig = config.trickle(sconfig)

    builder = WorkspaceBuilder(sconf=sconfig)

    with temp_session(server) as session:
        builder.build(session=session)

HOME=os.path.realpath(os.path.expanduser('~'))
    )

    # test order of `panes` (and pane_index) above aganist pane_dirs
    pane_paths = [
        '/usr/bin',
        '/usr',
        '/usr/sbin',
        os.path.realpath(os.path.expanduser('~')),
    ]

    s = session
    sconfig = kaptan.Kaptan(handler='yaml')
    sconfig = sconfig.import_config(yaml_config).get()
    sconfig = config.expand(sconfig)
    sconfig = config.trickle(sconfig)

    builder = WorkspaceBuilder(sconf=sconfig)

    window_count = len(session._windows)  # current window count
    assert len(s._windows) == window_count
    for w, wconf in builder.iter_create_windows(s):
        for p in builder.iter_create_panes(w, wconf):
            w.select_layout('tiled')  # fix glitch with pane size
            p = p
            assert len(s._windows) == window_count

        assert isinstance(w, Window)

        assert len(s._windows) == window_count
        window_count += 1

def test_before_load_throw_error_if_file_not_exists(server):
    config_script_not_exists = loadfixture(
        "workspacebuilder/config_script_not_exists.yaml"
    )
    sconfig = kaptan.Kaptan(handler='yaml')
    yaml = config_script_not_exists.format(
        fixtures_dir=fixtures_dir,
        script_not_exists=os.path.join(fixtures_dir, 'script_not_exists.sh'),
    )
    sconfig = sconfig.import_config(yaml).get()
    sconfig = config.expand(sconfig)
    sconfig = config.trickle(sconfig)

    builder = WorkspaceBuilder(sconf=sconfig)

    with temp_session(server) as sess:
        session_name = sess.name
        temp_session_exists = server.has_session(sess.name)
        assert temp_session_exists
        with pytest.raises((exc.BeforeLoadScriptNotExists, OSError)) as excinfo:
            builder.build(session=sess)
            excinfo.match(r'No such file or directory')
        result = server.has_session(session_name)
        assert not result, "Kills session if before_script doesn't exist"

def test_before_load_throw_error_if_retcode_error(server):
    config_script_fails = loadfixture("workspacebuilder/config_script_fails.yaml")
    sconfig = kaptan.Kaptan(handler='yaml')
    yaml = config_script_fails.format(
        fixtures_dir=fixtures_dir,
        script_failed=os.path.join(fixtures_dir, 'script_failed.sh'),
    )

    sconfig = sconfig.import_config(yaml).get()
    sconfig = config.expand(sconfig)
    sconfig = config.trickle(sconfig)

    builder = WorkspaceBuilder(sconf=sconfig)

    with temp_session(server) as sess:
        session_name = sess.name

        with pytest.raises(exc.BeforeLoadScriptError):
            builder.build(session=sess)

        result = server.has_session(session_name)
        assert not result, "Kills session if before_script exits with errcode"

def test_shell_command_before():
    """Config inheritance for the nested 'start_command'."""
    test_config = fixtures.shell_command_before.config_unexpanded
    test_config = config.expand(test_config)

    assert test_config == fixtures.shell_command_before.config_expanded

    test_config = config.trickle(test_config)
    assert test_config == fixtures.shell_command_before.config_after