Macro driver 

macro_rules! driver {
    ($plugin:ty $(,)?) => { ... };
}

Construct a PluginDriver for the given plugin type, with manifest_dir wired to the calling crate’s CARGO_MANIFEST_DIR. That lets .state_file("test_states/foo.pluginstate") resolve against the crate’s own directory regardless of where cargo test was launched.

truce_test::driver!(MyPlugin)
    .duration(Duration::from_millis(100))
    .state_file("test_states/preset.pluginstate")
    .run();