src/ui/lib/input_pipeline/src/testing_utilities.rs

// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#![cfg(test)]

use {
    crate::utils::Position,
    crate::{
        consumer_controls_binding, input_device, input_handler, keyboard_binding, mouse_binding,
        touch_binding,
    },
    assert_matches::assert_matches,
    fidl_fuchsia_input_report as fidl_input_report, fidl_fuchsia_ui_input as fidl_ui_input,
    fidl_fuchsia_ui_input3 as fidl_ui_input3, fidl_fuchsia_ui_pointerinjector as pointerinjector,
    fuchsia_zircon as zx,
    futures::FutureExt as _,
    maplit::hashmap,
    std::collections::HashMap,
    std::collections::HashSet,
};

/// Returns the current time as an i64 for InputReports and zx::Time for InputEvents.
pub fn event_times() -> (i64, zx::Time) {
    let event_time = zx::Time::get_monotonic();
    (event_time.into_nanos(), event_time)
}

/// Creates a [`fidl_input_report::InputReport`] with a keyboard report.
///
/// # Parameters
/// -`pressed_keys`: The input3 keys that will be added to the returned input report.
/// -`event_time`: The time in nanoseconds when the event was first recorded.
pub fn create_keyboard_input_report(
    pressed_keys: Vec<fidl_fuchsia_input::Key>,
    event_time: i64,
) -> fidl_input_report::InputReport {
    fidl_input_report::InputReport {
        event_time: Some(event_time),
        keyboard: Some(fidl_input_report::KeyboardInputReport {
            pressed_keys3: Some(pressed_keys),
            ..fidl_input_report::KeyboardInputReport::EMPTY
        }),
        mouse: None,
        touch: None,
        sensor: None,
        consumer_control: None,
        trace_id: None,
        ..fidl_input_report::InputReport::EMPTY
    }
}

/// Creates a new [input_device::InputEvent] from the provided components.
pub fn create_input_event(
    keyboard_event: keyboard_binding::KeyboardEvent,
    device_descriptor: &input_device::InputDeviceDescriptor,
    event_time: zx::Time,
    handled: input_device::Handled,
) -> input_device::InputEvent {
    input_device::InputEvent {
        device_event: input_device::InputDeviceEvent::Keyboard(keyboard_event),
        device_descriptor: device_descriptor.clone(),
        event_time,
        handled,
        trace_id: None,
    }
}

/// Creates a [`keyboard_binding::KeyboardEvent`] with the provided keys, meaning, and handled state.
///
/// # Parameters
/// - `key`: The input3 key which changed state.
/// - `event_type`: The input3 key event type (e.g. pressed, released).
/// - `modifiers`: The input3 modifiers that are to be included as pressed.
/// - `event_time`: The timestamp in nanoseconds when the event was recorded.
/// - `device_descriptor`: The device descriptor to add to the event.
/// - `handled`: Whether the event has been consumed by an upstream handler.
pub fn create_keyboard_event_with_handled(
    key: fidl_fuchsia_input::Key,
    event_type: fidl_fuchsia_ui_input3::KeyEventType,
    modifiers: Option<fidl_ui_input3::Modifiers>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
    keymap: Option<String>,
    key_meaning: Option<fidl_fuchsia_ui_input3::KeyMeaning>,
    handled: input_device::Handled,
) -> input_device::InputEvent {
    let keyboard_event = keyboard_binding::KeyboardEvent::new(key, event_type)
        .into_with_modifiers(modifiers)
        .into_with_keymap(keymap)
        .into_with_key_meaning(key_meaning);
    create_input_event(keyboard_event, device_descriptor, event_time, handled)
}

/// Creates a [`keyboard_binding::KeyboardEvent`] with the provided keys and meaning.
/// a repeat sequence.
///
/// # Parameters
/// - `key`: The input3 key which changed state.
/// - `event_type`: The input3 key event type (e.g. pressed, released).
/// - `modifiers`: The input3 modifiers that are to be included as pressed.
/// - `event_time`: The timestamp in nanoseconds when the event was recorded.
/// - `device_descriptor`: The device descriptor to add to the event.
/// - `repeat_sequence`: The sequence of this key event in the autorepeat process.
pub fn create_keyboard_event_with_key_meaning_and_repeat_sequence(
    key: fidl_fuchsia_input::Key,
    event_type: fidl_fuchsia_ui_input3::KeyEventType,
    modifiers: Option<fidl_ui_input3::Modifiers>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
    keymap: Option<String>,
    key_meaning: Option<fidl_fuchsia_ui_input3::KeyMeaning>,
    repeat_sequence: u32,
) -> input_device::InputEvent {
    let device_event = keyboard_binding::KeyboardEvent::new(key, event_type)
        .into_with_modifiers(modifiers)
        .into_with_key_meaning(key_meaning)
        .into_with_keymap(keymap)
        .into_with_repeat_sequence(repeat_sequence);
    create_input_event(device_event, device_descriptor, event_time, input_device::Handled::No)
}

/// Creates a [`keyboard_binding::KeyboardEvent`] with the provided keys and meaning.
///
/// # Parameters
/// - `key`: The input3 key which changed state.
/// - `event_type`: The input3 key event type (e.g. pressed, released).
/// - `modifiers`: The input3 modifiers that are to be included as pressed.
/// - `event_time`: The timestamp in nanoseconds when the event was recorded.
/// - `device_descriptor`: The device descriptor to add to the event.
pub fn create_keyboard_event_with_key_meaning(
    key: fidl_fuchsia_input::Key,
    event_type: fidl_fuchsia_ui_input3::KeyEventType,
    modifiers: Option<fidl_ui_input3::Modifiers>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
    keymap: Option<String>,
    key_meaning: Option<fidl_fuchsia_ui_input3::KeyMeaning>,
) -> input_device::InputEvent {
    create_keyboard_event_with_key_meaning_and_repeat_sequence(
        key,
        event_type,
        modifiers,
        event_time,
        device_descriptor,
        keymap,
        key_meaning,
        0,
    )
}

/// Creates a [`keyboard_binding::KeyboardEvent`] with the provided keys.
///
/// # Parameters
/// - `key`: The input3 key which changed state.
/// - `event_type`: The input3 key event type (e.g. pressed, released).
/// - `modifiers`: The input3 modifiers that are to be included as pressed.
/// - `event_time`: The timestamp in nanoseconds when the event was recorded.
/// - `device_descriptor`: The device descriptor to add to the event.
pub fn create_keyboard_event(
    key: fidl_fuchsia_input::Key,
    event_type: fidl_fuchsia_ui_input3::KeyEventType,
    modifiers: Option<fidl_ui_input3::Modifiers>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
    keymap: Option<String>,
) -> input_device::InputEvent {
    create_keyboard_event_with_key_meaning(
        key,
        event_type,
        modifiers,
        event_time,
        device_descriptor,
        keymap,
        None,
    )
}

/// Creates a fake input event with the given event time.  Please do not
/// read into other event fields.
pub fn create_fake_input_event(event_time: zx::Time) -> input_device::InputEvent {
    input_device::InputEvent {
        event_time,
        device_event: input_device::InputDeviceEvent::Fake,
        device_descriptor: input_device::InputDeviceDescriptor::Fake,
        handled: input_device::Handled::No,
        trace_id: None,
    }
}

/// Creates a fake handled input event with the given event time.  Please do not
/// read into other event fields.
pub fn create_fake_handled_input_event(event_time: zx::Time) -> input_device::InputEvent {
    input_device::InputEvent {
        event_time,
        device_event: input_device::InputDeviceEvent::Fake,
        device_descriptor: input_device::InputDeviceDescriptor::Fake,
        handled: input_device::Handled::Yes,
        trace_id: None,
    }
}

/// Creates an [`input_device::InputDeviceDescriptor`] for a consumer controls device.
pub fn consumer_controls_device_descriptor() -> input_device::InputDeviceDescriptor {
    input_device::InputDeviceDescriptor::ConsumerControls(
        consumer_controls_binding::ConsumerControlsDeviceDescriptor {
            buttons: vec![
                fidl_input_report::ConsumerControlButton::CameraDisable,
                fidl_input_report::ConsumerControlButton::FactoryReset,
                fidl_input_report::ConsumerControlButton::MicMute,
                fidl_input_report::ConsumerControlButton::Pause,
                fidl_input_report::ConsumerControlButton::VolumeDown,
                fidl_input_report::ConsumerControlButton::VolumeUp,
            ],
        },
    )
}

/// Creates a [`fidl_input_report::InputReport`] with a consumer control report.
///
/// # Parameters
/// - `buttons`: The buttons in the consumer control report.
/// - `event_time`: The time of event.
pub fn create_consumer_control_input_report(
    buttons: Vec<fidl_input_report::ConsumerControlButton>,
    event_time: i64,
) -> fidl_input_report::InputReport {
    fidl_input_report::InputReport {
        event_time: Some(event_time),
        keyboard: None,
        mouse: None,
        touch: None,
        sensor: None,
        consumer_control: Some(fidl_input_report::ConsumerControlInputReport {
            pressed_buttons: Some(buttons),
            ..fidl_input_report::ConsumerControlInputReport::EMPTY
        }),
        trace_id: None,
        ..fidl_input_report::InputReport::EMPTY
    }
}

/// Creates a [`consumer_controls_binding::ConsumerControlsEvent`] with the provided parameters.
///
/// # Parameters
/// - `pressed_buttons`: The buttons to report in the event.
/// - `event_time`: The time of event.
/// - `device_descriptor`: The device descriptor to add to the event.
/// - `handled`: Whether the event has been consumed.
pub fn create_consumer_controls_event_with_handled(
    pressed_buttons: Vec<fidl_input_report::ConsumerControlButton>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
    handled: input_device::Handled,
) -> input_device::InputEvent {
    input_device::InputEvent {
        device_event: input_device::InputDeviceEvent::ConsumerControls(
            consumer_controls_binding::ConsumerControlsEvent::new(pressed_buttons),
        ),
        device_descriptor: device_descriptor.clone(),
        event_time,
        handled,
        trace_id: None,
    }
}

/// Creates a [`consumer_controls_binding::ConsumerControlsEvent`] with the provided parameters.
///
/// # Parameters
/// - `pressed_buttons`: The buttons to report in the event.
/// - `event_time`: The time of event.
/// - `device_descriptor`: The device descriptor to add to the event.
pub fn create_consumer_controls_event(
    pressed_buttons: Vec<fidl_input_report::ConsumerControlButton>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
) -> input_device::InputEvent {
    create_consumer_controls_event_with_handled(
        pressed_buttons,
        event_time,
        device_descriptor,
        input_device::Handled::No,
    )
}

/// Creates a [`fidl_input_report::InputReport`] with a mouse report.
///
/// # Parameters
/// - `location`: The movement or position of the mouse report, in input device coordinates.
///     [`MouseLocation::Relative`] represents movement, and
///     [`MouseLocation::Absolute`] represents position.
/// - `wheel_delta_v`: The wheel delta in vertical.
/// - `wheel_delta_h`: The wheel delta in horizontal.
/// - `buttons`: The buttons to report as pressed in the mouse report.
/// - `event_time`: The time of event.
pub fn create_mouse_input_report(
    location: mouse_binding::MouseLocation,
    scroll_v: Option<i64>,
    scroll_h: Option<i64>,
    buttons: Vec<u8>,
    event_time: i64,
) -> fidl_input_report::InputReport {
    fidl_input_report::InputReport {
        event_time: Some(event_time),
        keyboard: None,
        mouse: Some(fidl_input_report::MouseInputReport {
            movement_x: match location {
                mouse_binding::MouseLocation::Relative(mouse_binding::RelativeLocation {
                    counts: Position { x, .. },
                    millimeters: Position { .. },
                }) => Some(x as i64),
                _ => None,
            },
            movement_y: match location {
                mouse_binding::MouseLocation::Relative(mouse_binding::RelativeLocation {
                    counts: Position { y, .. },
                    millimeters: Position { .. },
                }) => Some(y as i64),
                _ => None,
            },
            position_x: match location {
                mouse_binding::MouseLocation::Absolute(Position { x, .. }) => Some(x as i64),
                _ => None,
            },
            position_y: match location {
                mouse_binding::MouseLocation::Absolute(Position { y, .. }) => Some(y as i64),
                _ => None,
            },
            scroll_v: scroll_v,
            scroll_h: scroll_h,
            pressed_buttons: Some(buttons),
            ..fidl_input_report::MouseInputReport::EMPTY
        }),
        touch: None,
        sensor: None,
        consumer_control: None,
        trace_id: None,
        ..fidl_input_report::InputReport::EMPTY
    }
}

/// Creates a [`mouse_binding::MouseEvent`] with the provided parameters.
///
/// # Parameters
/// - `location`: The mouse location to report in the event.
/// - `wheel_delta_v`: The wheel delta in vertical.
/// - `wheel_delta_h`: The wheel delta in horizontal.
/// - `phase`: The phase of the buttons in the event.
/// - `buttons`: The buttons to report in the event.
/// - `event_time`: The time of event.
/// - `device_descriptor`: The device descriptor to add to the event.
pub fn create_mouse_event_with_handled(
    location: mouse_binding::MouseLocation,
    wheel_delta_v: Option<i64>,
    wheel_delta_h: Option<i64>,
    phase: mouse_binding::MousePhase,
    affected_buttons: HashSet<mouse_binding::MouseButton>,
    pressed_buttons: HashSet<mouse_binding::MouseButton>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
    handled: input_device::Handled,
) -> input_device::InputEvent {
    input_device::InputEvent {
        device_event: input_device::InputDeviceEvent::Mouse(mouse_binding::MouseEvent::new(
            location,
            wheel_delta_v,
            wheel_delta_h,
            phase,
            affected_buttons,
            pressed_buttons,
        )),
        device_descriptor: device_descriptor.clone(),
        event_time,
        handled,
        trace_id: None,
    }
}

/// Creates a [`mouse_binding::MouseEvent`] with the provided parameters.
///
/// # Parameters
/// - `location`: The mouse location to report in the event.
/// - `phase`: The phase of the buttons in the event.
/// - `buttons`: The buttons to report in the event.
/// - `event_time`: The time of event.
/// - `device_descriptor`: The device descriptor to add to the event.
pub fn create_mouse_event(
    location: mouse_binding::MouseLocation,
    wheel_delta_v: Option<i64>,
    wheel_delta_h: Option<i64>,
    phase: mouse_binding::MousePhase,
    affected_buttons: HashSet<mouse_binding::MouseButton>,
    pressed_buttons: HashSet<mouse_binding::MouseButton>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
) -> input_device::InputEvent {
    create_mouse_event_with_handled(
        location,
        wheel_delta_v,
        wheel_delta_h,
        phase,
        affected_buttons,
        pressed_buttons,
        event_time,
        device_descriptor,
        input_device::Handled::No,
    )
}

/// Creates a [`pointerinjector::Event`] representing a mouse event.
///
/// # Parameters
/// - `phase`: The phase of the touch contact.
/// - `contact`: The touch contact to create the event for.
/// - `position`: The position of the contact in the viewport space.
/// - `relative_motion`: The relative motion fopr the event.
/// - `wheel_delta_v`: The wheel delta in vertical.
/// - `wheel_delta_h`: The wheel delta in horizontal.
/// - `event_time`: The time in nanoseconds when the event was first recorded.
pub fn create_mouse_pointer_sample_event(
    phase: pointerinjector::EventPhase,
    buttons: Vec<mouse_binding::MouseButton>,
    position: crate::utils::Position,
    relative_motion: Option<[f32; 2]>,
    wheel_delta_v: Option<i64>,
    wheel_delta_h: Option<i64>,
    event_time: zx::Time,
) -> pointerinjector::Event {
    let pointer_sample = pointerinjector::PointerSample {
        pointer_id: Some(0),
        phase: Some(phase),
        position_in_viewport: Some([position.x, position.y]),
        scroll_v: wheel_delta_v,
        scroll_h: wheel_delta_h,
        pressed_buttons: Some(buttons),
        relative_motion,
        ..pointerinjector::PointerSample::EMPTY
    };
    let data = pointerinjector::Data::PointerSample(pointer_sample);

    pointerinjector::Event {
        timestamp: Some(event_time.into_nanos()),
        data: Some(data),
        ..pointerinjector::Event::EMPTY
    }
}

/// Creates a [`fidl_input_report::InputReport`] with a touch report.
///
/// # Parameters
/// - `contacts`: The contacts in the touch report.
/// - `event_time`: The time of event.
pub fn create_touch_input_report(
    contacts: Vec<fidl_input_report::ContactInputReport>,
    event_time: i64,
) -> fidl_input_report::InputReport {
    fidl_input_report::InputReport {
        event_time: Some(event_time),
        keyboard: None,
        mouse: None,
        touch: Some(fidl_input_report::TouchInputReport {
            contacts: Some(contacts),
            pressed_buttons: None,
            ..fidl_input_report::TouchInputReport::EMPTY
        }),
        sensor: None,
        consumer_control: None,
        trace_id: None,
        ..fidl_input_report::InputReport::EMPTY
    }
}

pub fn create_touch_contact(id: u32, position: Position) -> touch_binding::TouchContact {
    touch_binding::TouchContact { id, position, pressure: None, contact_size: None }
}

/// Creates a [`touch_binding::TouchEvent`] with the provided parameters.
///
/// # Parameters
/// - `contacts`: The contacts in the touch report.
/// - `event_time`: The time of event.
/// - `device_descriptor`: The device descriptor to add to the event.
/// - `handled`: Whether the event has been consumed.
pub fn create_touch_event_with_handled(
    mut contacts: HashMap<fidl_ui_input::PointerEventPhase, Vec<touch_binding::TouchContact>>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
    handled: input_device::Handled,
) -> input_device::InputEvent {
    contacts.entry(fidl_ui_input::PointerEventPhase::Add).or_insert(vec![]);
    contacts.entry(fidl_ui_input::PointerEventPhase::Down).or_insert(vec![]);
    contacts.entry(fidl_ui_input::PointerEventPhase::Move).or_insert(vec![]);
    contacts.entry(fidl_ui_input::PointerEventPhase::Up).or_insert(vec![]);
    contacts.entry(fidl_ui_input::PointerEventPhase::Remove).or_insert(vec![]);

    let injector_contacts = hashmap! {
        pointerinjector::EventPhase::Add =>
        contacts.get(&fidl_ui_input::PointerEventPhase::Add).unwrap().clone(),
        pointerinjector::EventPhase::Change =>
        contacts.get(&fidl_ui_input::PointerEventPhase::Move).unwrap().clone(),
        pointerinjector::EventPhase::Remove =>
        contacts.get(&fidl_ui_input::PointerEventPhase::Remove).unwrap().clone(),
    };
    input_device::InputEvent {
        device_event: input_device::InputDeviceEvent::Touch(touch_binding::TouchEvent {
            contacts,
            injector_contacts,
        }),
        device_descriptor: device_descriptor.clone(),
        event_time,
        handled: handled,
        trace_id: None,
    }
}

/// Creates a [`touch_binding::TouchEvent`] with the provided parameters.
///
/// # Parameters
/// - `contacts`: The contacts in the touch report.
/// - `event_time`: The time of event.
/// - `device_descriptor`: The device descriptor to add to the event.
pub fn create_touch_event(
    contacts: HashMap<fidl_ui_input::PointerEventPhase, Vec<touch_binding::TouchContact>>,
    event_time: zx::Time,
    device_descriptor: &input_device::InputDeviceDescriptor,
) -> input_device::InputEvent {
    create_touch_event_with_handled(
        contacts,
        event_time,
        device_descriptor,
        input_device::Handled::No,
    )
}

/// Creates a [`fidl_ui_scenic::Command`] representing the given touch contact.
///
/// # Parameters
/// - `phase`: The phase of the touch contact.
/// - `contact`: The touch contact to create the event for.
/// - `position`: The position of the contact in the viewport space.
/// - `event_time`: The time in nanoseconds when the event was first recorded.
pub fn create_touch_pointer_sample_event(
    phase: pointerinjector::EventPhase,
    contact: &touch_binding::TouchContact,
    position: crate::utils::Position,
    event_time: zx::Time,
) -> pointerinjector::Event {
    let pointer_sample = pointerinjector::PointerSample {
        pointer_id: Some(contact.id),
        phase: Some(phase),
        position_in_viewport: Some([position.x, position.y]),
        scroll_v: None,
        scroll_h: None,
        pressed_buttons: None,
        ..pointerinjector::PointerSample::EMPTY
    };
    let data = pointerinjector::Data::PointerSample(pointer_sample);

    pointerinjector::Event {
        timestamp: Some(event_time.into_nanos()),
        data: Some(data),
        trace_flow_id: Some(fuchsia_trace::generate_nonce()),
        ..pointerinjector::Event::EMPTY
    }
}

/// Asserts that the given sequence of input reports generates the provided input events
/// when the reports are processed by the given device type.
#[macro_export]
macro_rules! assert_input_report_sequence_generates_events {
    (
        // The input reports to process.
        input_reports: $input_reports:expr,
        // The events which are expected.
        expected_events: $expected_events:expr,
        // The descriptor for the device that is sent to the input processor.
        device_descriptor: $device_descriptor:expr,
        // The type of device generating the events.
        device_type: $DeviceType:ty,
    ) => {
        let mut previous_report: Option<fidl_fuchsia_input_report::InputReport> = None;
        let (event_sender, mut event_receiver) = futures::channel::mpsc::channel(std::cmp::max(
            $input_reports.len(),
            $expected_events.len(),
        ));

        // Send all the reports prior to verifying the received events.
        for report in $input_reports {
            previous_report = <$DeviceType>::process_reports(
                report,
                previous_report,
                &$device_descriptor,
                &mut event_sender.clone(),
            );
        }

        for expected_event in $expected_events {
            let input_event = event_receiver.next().await;
            match input_event {
                Some(mut received_event) => {
                    // The trace_id field is set to a nonce value by process_reports(), so a naive
                    // comparison to an expected event will not match. Here, we set it to None to
                    // allow comparing against an expected event, but we ensure trace_id is set
                    // properly with another test.
                    received_event.trace_id = None;
                    pretty_assertions::assert_eq!(expected_event, received_event)
                }
                _ => assert!(false),
            };
        }
    };
}

/// Asserts that the given sequence of input events generates the provided Scenic commands when the
/// events are processed by the given input handler.
#[macro_export]
macro_rules! assert_input_event_sequence_generates_scenic_events {
    (
        // The input handler that will handle input events.
        input_handler: $input_handler:expr,
        // The InputEvents to handle.
        input_events: $input_events:expr,
        // The commands the Scenic session should receive.
        expected_commands: $expected_commands:expr,
        // The Scenic session request stream.
        scenic_session_request_stream: $scenic_session_request_stream:expr,
        // A function to validate the Scenic commands.
        assert_command: $assert_command:expr,
    ) => {
        for input_event in $input_events {
            assert_matches!(
                $input_handler.clone().handle_input_event(input_event).await.as_slice(),
                [input_device::InputEvent { handled: input_device::Handled::Yes, .. }]
            );
        }

        let mut expected_command_iter = $expected_commands.into_iter().peekable();
        while let Some(request) = $scenic_session_request_stream.next().await {
            match request {
                Ok(fidl_ui_scenic::SessionRequest::Enqueue { cmds, control_handle: _ }) => {
                    let mut command_iter = cmds.into_iter().peekable();
                    while let Some(command) = command_iter.next() {
                        let expected_command = expected_command_iter.next().unwrap();
                        $assert_command(command, expected_command);

                        // All the expected events have been received, so make sure no more events
                        // are present before returning.
                        if expected_command_iter.peek().is_none() {
                            assert!(command_iter.peek().is_none());
                            return;
                        }
                    }
                }
                _ => {
                    assert!(false);
                }
            }
        }
    };
}

/// Asserts that the given sequence of input events generates the provided media buttons events when
/// the input events are processed by the given input handler.
#[macro_export]
macro_rules! assert_input_event_sequence_generates_media_buttons_events {
    (
        // The input handler that will handle input events.
        input_handler: $input_handler:expr,
        // The InputEvents to handle.
        input_events: $input_events:expr,
        // The events the listeners should receive.
        expected_events: $expected_events:expr,
        // The media buttons listener request stream(s).
        media_buttons_listener_request_stream: $media_buttons_listener_request_stream:expr,
    ) => {
        fasync::Task::local(async move {
            for input_event in $input_events {
                assert_matches!(
                    $input_handler.clone().handle_input_event(input_event).await.as_slice(),
                    [input_device::InputEvent { handled: input_device::Handled::Yes, .. }]
                );
            }
        })
        .detach();

        for mut stream in $media_buttons_listener_request_stream {
            let mut expected_command_iter = $expected_events.clone().into_iter().peekable();
            while let Some(request) = stream.next().await {
                match request {
                    Ok(fidl_ui_policy::MediaButtonsListenerRequest::OnEvent {
                        event,
                        responder,
                    }) => {
                        let expected_command = expected_command_iter.next().unwrap();
                        pretty_assertions::assert_eq!(event, expected_command);
                        let _ = responder.send();

                        // All the expected events have been received, so make sure no more
                        // events are present before continuing to the next stream.
                        if expected_command_iter.peek().is_none() {
                            break;
                        }
                    }
                    _ => assert!(false),
                }
            }
        }
    };
}

/// Asserts that the given sequence of input events are ignored by the provided handler and request stream.
pub async fn assert_handler_ignores_input_event_sequence(
    // The handler processing events.
    input_handler: std::rc::Rc<dyn input_handler::InputHandler>,
    // The InputEvents to handle.
    input_events: Vec<input_device::InputEvent>,
    // The listener request stream.
    mut request_stream: impl futures::StreamExt + std::marker::Unpin,
) {
    for input_event in input_events {
        assert_matches!(
            input_handler.clone().handle_input_event(input_event).await.as_slice(),
            [input_device::InputEvent { handled: input_device::Handled::Yes, .. }]
        );
    }

    // The request stream should not receive any events.
    assert!(request_stream.next().now_or_never().is_none());
}