mod parallel_scope; use core::{marker::PhantomData, panic::Location}; use super::{ Deferred, IntoObserverSystem, IntoSystem, RegisterSystem, Resource, RunSystemCachedWith, UnregisterSystem, }; use crate::{ self as bevy_ecs, bundle::{Bundle, InsertMode}, change_detection::Mut, component::{Component, ComponentId, ComponentInfo, Mutable}, entity::{Entities, Entity, EntityCloneBuilder}, event::{Event, SendEvent}, observer::{Observer, TriggerEvent, TriggerTargets}, schedule::ScheduleLabel, system::{input::SystemInput, RunSystemWithInput, SystemId}, world::{ command_queue::RawCommandQueue, unsafe_world_cell::UnsafeWorldCell, Command, CommandQueue, EntityWorldMut, FromWorld, SpawnBatchIter, World, }, }; use bevy_ptr::OwningPtr; use bevy_utils::tracing::{error, info}; pub use parallel_scope::*; /// A [`Command`] queue to perform structural changes to the [`World`]. /// /// Since each command requires exclusive access to the `World`, /// all queued commands are automatically applied in sequence /// when the `ApplyDeferred` system runs (see [`ApplyDeferred`] documentation for more details). /// /// Each command can be used to modify the [`World`] in arbitrary ways: /// * spawning or despawning entities /// * inserting components on new or existing entities /// * inserting resources /// * etc. /// /// For a version of [`Commands`] that works in parallel contexts (such as /// within [`Query::par_iter`](crate::system::Query::par_iter)) see /// [`ParallelCommands`] /// /// # Usage /// /// Add `mut commands: Commands` as a function argument to your system to get a /// copy of this struct that will be applied the next time a copy of [`ApplyDeferred`] runs. /// Commands are almost always used as a [`SystemParam`](crate::system::SystemParam). /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// fn my_system(mut commands: Commands) { /// // ... /// } /// # bevy_ecs::system::assert_is_system(my_system); /// ``` /// /// # Implementing /// /// Each built-in command is implemented as a separate method, e.g. [`Commands::spawn`]. /// In addition to the pre-defined command methods, you can add commands with any arbitrary /// behavior using [`Commands::queue`], which accepts any type implementing [`Command`]. /// /// Since closures and other functions implement this trait automatically, this allows one-shot, /// anonymous custom commands. /// /// ``` /// # use bevy_ecs::prelude::*; /// # fn foo(mut commands: Commands) { /// // NOTE: type inference fails here, so annotations are required on the closure. /// commands.queue(|w: &mut World| { /// // Mutate the world however you want... /// # todo!(); /// }); /// # } /// ``` /// /// [`ApplyDeferred`]: crate::schedule::ApplyDeferred pub struct Commands<'w, 's> { queue: InternalQueue<'s>, entities: &'w Entities, } // SAFETY: All commands [`Command`] implement [`Send`] unsafe impl Send for Commands<'_, '_> {} // SAFETY: `Commands` never gives access to the inner commands. unsafe impl Sync for Commands<'_, '_> {} const _: () = { type __StructFieldsAlias<'w, 's> = (Deferred<'s, CommandQueue>, &'w Entities); #[doc(hidden)] pub struct FetchState { state: <__StructFieldsAlias<'static, 'static> as bevy_ecs::system::SystemParam>::State, } // SAFETY: Only reads Entities unsafe impl bevy_ecs::system::SystemParam for Commands<'_, '_> { type State = FetchState; type Item<'w, 's> = Commands<'w, 's>; fn init_state( world: &mut World, system_meta: &mut bevy_ecs::system::SystemMeta, ) -> Self::State { FetchState { state: <__StructFieldsAlias<'_, '_> as bevy_ecs::system::SystemParam>::init_state( world, system_meta, ), } } unsafe fn new_archetype( state: &mut Self::State, archetype: &bevy_ecs::archetype::Archetype, system_meta: &mut bevy_ecs::system::SystemMeta, ) { // SAFETY: Caller guarantees the archetype is from the world used in `init_state` unsafe { <__StructFieldsAlias<'_, '_> as bevy_ecs::system::SystemParam>::new_archetype( &mut state.state, archetype, system_meta, ); }; } fn apply( state: &mut Self::State, system_meta: &bevy_ecs::system::SystemMeta, world: &mut World, ) { <__StructFieldsAlias<'_, '_> as bevy_ecs::system::SystemParam>::apply( &mut state.state, system_meta, world, ); } fn queue( state: &mut Self::State, system_meta: &bevy_ecs::system::SystemMeta, world: bevy_ecs::world::DeferredWorld, ) { <__StructFieldsAlias<'_, '_> as bevy_ecs::system::SystemParam>::queue( &mut state.state, system_meta, world, ); } #[inline] unsafe fn validate_param( state: &Self::State, system_meta: &bevy_ecs::system::SystemMeta, world: UnsafeWorldCell, ) -> bool { <(Deferred, &Entities) as bevy_ecs::system::SystemParam>::validate_param( &state.state, system_meta, world, ) } #[inline] unsafe fn get_param<'w, 's>( state: &'s mut Self::State, system_meta: &bevy_ecs::system::SystemMeta, world: UnsafeWorldCell<'w>, change_tick: bevy_ecs::component::Tick, ) -> Self::Item<'w, 's> { let(f0, f1) = <(Deferred<'s, CommandQueue>, &'w Entities) as bevy_ecs::system::SystemParam>::get_param(&mut state.state, system_meta, world, change_tick); Commands { queue: InternalQueue::CommandQueue(f0), entities: f1, } } } // SAFETY: Only reads Entities unsafe impl<'w, 's> bevy_ecs::system::ReadOnlySystemParam for Commands<'w, 's> where Deferred<'s, CommandQueue>: bevy_ecs::system::ReadOnlySystemParam, &'w Entities: bevy_ecs::system::ReadOnlySystemParam, { } }; enum InternalQueue<'s> { CommandQueue(Deferred<'s, CommandQueue>), RawCommandQueue(RawCommandQueue), } impl<'w, 's> Commands<'w, 's> { /// Returns a new `Commands` instance from a [`CommandQueue`] and a [`World`]. /// /// It is not required to call this constructor when using `Commands` as a [system parameter]. /// /// [system parameter]: crate::system::SystemParam pub fn new(queue: &'s mut CommandQueue, world: &'w World) -> Self { Self::new_from_entities(queue, &world.entities) } /// Returns a new `Commands` instance from a [`CommandQueue`] and an [`Entities`] reference. /// /// It is not required to call this constructor when using `Commands` as a [system parameter]. /// /// [system parameter]: crate::system::SystemParam pub fn new_from_entities(queue: &'s mut CommandQueue, entities: &'w Entities) -> Self { Self { queue: InternalQueue::CommandQueue(Deferred(queue)), entities, } } /// Returns a new `Commands` instance from a [`RawCommandQueue`] and an [`Entities`] reference. /// /// This is used when constructing [`Commands`] from a [`DeferredWorld`](crate::world::DeferredWorld). /// /// # Safety /// /// * Caller ensures that `queue` must outlive 'w pub(crate) unsafe fn new_raw_from_entities( queue: RawCommandQueue, entities: &'w Entities, ) -> Self { Self { queue: InternalQueue::RawCommandQueue(queue), entities, } } /// Returns a [`Commands`] with a smaller lifetime. /// This is useful if you have `&mut Commands` but need `Commands`. /// /// # Examples /// /// ``` /// # use bevy_ecs::prelude::*; /// fn my_system(mut commands: Commands) { /// // We do our initialization in a separate function, /// // which expects an owned `Commands`. /// do_initialization(commands.reborrow()); /// /// // Since we only reborrowed the commands instead of moving them, we can still use them. /// commands.spawn_empty(); /// } /// # /// # fn do_initialization(_: Commands) {} /// ``` pub fn reborrow(&mut self) -> Commands<'w, '_> { Commands { queue: match &mut self.queue { InternalQueue::CommandQueue(queue) => InternalQueue::CommandQueue(queue.reborrow()), InternalQueue::RawCommandQueue(queue) => { InternalQueue::RawCommandQueue(queue.clone()) } }, entities: self.entities, } } /// Take all commands from `other` and append them to `self`, leaving `other` empty pub fn append(&mut self, other: &mut CommandQueue) { match &mut self.queue { InternalQueue::CommandQueue(queue) => queue.bytes.append(&mut other.bytes), InternalQueue::RawCommandQueue(queue) => { // SAFETY: Pointers in `RawCommandQueue` are never null unsafe { queue.bytes.as_mut() }.append(&mut other.bytes); } } } /// Clones an entity and allows configuring cloning behavior using [`EntityCloneBuilder`], returning [`EntityCommands`] of the cloned entity. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// /// #[derive(Component, Clone)] /// struct ComponentA(u32); /// #[derive(Component, Clone)] /// struct ComponentB(u32); /// /// fn example_system(mut commands: Commands) { /// // Create a new entity and retrieve its id. /// let entity = commands.spawn((ComponentA(10), ComponentB(20))).id(); /// /// // Create a clone of the first entity, but without ComponentB /// let entity_clone = commands.clone_entity_with(entity, |builder| { /// builder.deny::(); /// }).id(); /// } /// # bevy_ecs::system::assert_is_system(example_system); pub fn clone_entity_with( &mut self, entity: Entity, f: impl FnOnce(&mut EntityCloneBuilder) + Send + Sync + 'static, ) -> EntityCommands<'_> { let cloned_entity = self.spawn_empty().id(); self.queue(move |world: &mut World| { let mut builder = EntityCloneBuilder::new(world); f(&mut builder); builder.clone_entity(entity, cloned_entity); }); EntityCommands { commands: self.reborrow(), entity: cloned_entity, } } /// Clones an entity and returns [`EntityCommands`] of the cloned entity. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// /// #[derive(Component, Clone)] /// struct ComponentA(u32); /// #[derive(Component, Clone)] /// struct ComponentB(u32); /// /// fn example_system(mut commands: Commands) { /// // Create a new entity and retrieve its id. /// let entity = commands.spawn((ComponentA(10), ComponentB(20))).id(); /// /// // Create a clone of the first entity /// let entity_clone = commands.clone_entity(entity).id(); /// } /// # bevy_ecs::system::assert_is_system(example_system); pub fn clone_entity(&mut self, entity: Entity) -> EntityCommands<'_> { self.clone_entity_with(entity, |_| {}) } /// Reserves a new empty [`Entity`] to be spawned, and returns its corresponding [`EntityCommands`]. /// /// See [`World::spawn_empty`] for more details. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// /// #[derive(Component)] /// struct Label(&'static str); /// #[derive(Component)] /// struct Strength(u32); /// #[derive(Component)] /// struct Agility(u32); /// /// fn example_system(mut commands: Commands) { /// // Create a new empty entity and retrieve its id. /// let empty_entity = commands.spawn_empty().id(); /// /// // Create another empty entity, then add some component to it /// commands.spawn_empty() /// // adds a new component bundle to the entity /// .insert((Strength(1), Agility(2))) /// // adds a single component to the entity /// .insert(Label("hello world")); /// } /// # bevy_ecs::system::assert_is_system(example_system); /// ``` /// /// # See also /// /// - [`spawn`](Self::spawn) to spawn an entity with a bundle. /// - [`spawn_batch`](Self::spawn_batch) to spawn entities with a bundle each. pub fn spawn_empty(&mut self) -> EntityCommands { let entity = self.entities.reserve_entity(); EntityCommands { entity, commands: self.reborrow(), } } /// Pushes a [`Command`] to the queue for creating a new [`Entity`] if the given one does not exists, /// and returns its corresponding [`EntityCommands`]. /// /// This method silently fails by returning [`EntityCommands`] /// even if the given `Entity` cannot be spawned. /// /// See [`World::get_or_spawn`] for more details. /// /// # Note /// /// Spawning a specific `entity` value is rarely the right choice. Most apps should favor /// [`Commands::spawn`]. This method should generally only be used for sharing entities across /// apps, and only when they have a scheme worked out to share an ID space (which doesn't happen /// by default). #[deprecated(since = "0.15.0", note = "use Commands::spawn instead")] pub fn get_or_spawn(&mut self, entity: Entity) -> EntityCommands { self.queue(move |world: &mut World| { #[allow(deprecated)] world.get_or_spawn(entity); }); EntityCommands { entity, commands: self.reborrow(), } } /// Pushes a [`Command`] to the queue for creating a new entity with the given [`Bundle`]'s components, /// and returns its corresponding [`EntityCommands`]. /// /// In case multiple bundles of the same [`Bundle`] type need to be spawned, /// [`spawn_batch`](Self::spawn_batch) should be used for better performance. /// /// # Example /// /// ``` /// use bevy_ecs::prelude::*; /// /// #[derive(Component)] /// struct Component1; /// #[derive(Component)] /// struct Component2; /// #[derive(Component)] /// struct Label(&'static str); /// #[derive(Component)] /// struct Strength(u32); /// #[derive(Component)] /// struct Agility(u32); /// /// #[derive(Bundle)] /// struct ExampleBundle { /// a: Component1, /// b: Component2, /// } /// /// fn example_system(mut commands: Commands) { /// // Create a new entity with a single component. /// commands.spawn(Component1); /// /// // Create a new entity with a component bundle. /// commands.spawn(ExampleBundle { /// a: Component1, /// b: Component2, /// }); /// /// commands /// // Create a new entity with two components using a "tuple bundle". /// .spawn((Component1, Component2)) /// // `spawn returns a builder, so you can insert more bundles like this: /// .insert((Strength(1), Agility(2))) /// // or insert single components like this: /// .insert(Label("hello world")); /// } /// # bevy_ecs::system::assert_is_system(example_system); /// ``` /// /// # See also /// /// - [`spawn_empty`](Self::spawn_empty) to spawn an entity without any components. /// - [`spawn_batch`](Self::spawn_batch) to spawn entities with a bundle each. #[track_caller] pub fn spawn(&mut self, bundle: T) -> EntityCommands { let mut entity = self.spawn_empty(); entity.insert(bundle); entity } /// Returns the [`EntityCommands`] for the requested [`Entity`]. /// /// # Panics /// /// This method panics if the requested entity does not exist. /// /// # Example /// /// ``` /// use bevy_ecs::prelude::*; /// /// #[derive(Component)] /// struct Label(&'static str); /// #[derive(Component)] /// struct Strength(u32); /// #[derive(Component)] /// struct Agility(u32); /// /// fn example_system(mut commands: Commands) { /// // Create a new, empty entity /// let entity = commands.spawn_empty().id(); /// /// commands.entity(entity) /// // adds a new component bundle to the entity /// .insert((Strength(1), Agility(2))) /// // adds a single component to the entity /// .insert(Label("hello world")); /// } /// # bevy_ecs::system::assert_is_system(example_system); /// ``` /// /// # See also /// /// - [`get_entity`](Self::get_entity) for the fallible version. #[inline] #[track_caller] pub fn entity(&mut self, entity: Entity) -> EntityCommands { #[inline(never)] #[cold] #[track_caller] fn panic_no_entity(entity: Entity) -> ! { panic!( "Attempting to create an EntityCommands for entity {entity:?}, which doesn't exist.", ); } match self.get_entity(entity) { Some(entity) => entity, None => panic_no_entity(entity), } } /// Returns the [`EntityCommands`] for the requested [`Entity`], if it exists. /// /// Returns `None` if the entity does not exist. /// /// This method does not guarantee that `EntityCommands` will be successfully applied, /// since another command in the queue may delete the entity before them. /// /// # Example /// /// ``` /// use bevy_ecs::prelude::*; /// /// #[derive(Component)] /// struct Label(&'static str); /// fn example_system(mut commands: Commands) { /// // Create a new, empty entity /// let entity = commands.spawn_empty().id(); /// /// // Get the entity if it still exists, which it will in this case /// if let Some(mut entity_commands) = commands.get_entity(entity) { /// // adds a single component to the entity /// entity_commands.insert(Label("hello world")); /// } /// } /// # bevy_ecs::system::assert_is_system(example_system); /// ``` /// /// # See also /// /// - [`entity`](Self::entity) for the panicking version. #[inline] #[track_caller] pub fn get_entity(&mut self, entity: Entity) -> Option { self.entities.contains(entity).then_some(EntityCommands { entity, commands: self.reborrow(), }) } /// Pushes a [`Command`] to the queue for creating entities with a particular [`Bundle`] type. /// /// `bundles_iter` is a type that can be converted into a [`Bundle`] iterator /// (it can also be a collection). /// /// This method is equivalent to iterating `bundles_iter` /// and calling [`spawn`](Self::spawn) on each bundle, /// but it is faster due to memory pre-allocation. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// # #[derive(Component)] /// # struct Name(String); /// # #[derive(Component)] /// # struct Score(u32); /// # /// # fn system(mut commands: Commands) { /// commands.spawn_batch(vec![ /// ( /// Name("Alice".to_string()), /// Score(0), /// ), /// ( /// Name("Bob".to_string()), /// Score(0), /// ), /// ]); /// # } /// # bevy_ecs::system::assert_is_system(system); /// ``` /// /// # See also /// /// - [`spawn`](Self::spawn) to spawn an entity with a bundle. /// - [`spawn_empty`](Self::spawn_empty) to spawn an entity without any components. #[track_caller] pub fn spawn_batch(&mut self, bundles_iter: I) where I: IntoIterator + Send + Sync + 'static, I::Item: Bundle, { self.queue(spawn_batch(bundles_iter)); } /// Pushes a generic [`Command`] to the command queue. /// /// `command` can be a built-in command, custom struct that implements [`Command`] or a closure /// that takes [`&mut World`](World) as an argument. /// # Example /// /// ``` /// # use bevy_ecs::{world::Command, prelude::*}; /// #[derive(Resource, Default)] /// struct Counter(u64); /// /// struct AddToCounter(u64); /// /// impl Command for AddToCounter { /// fn apply(self, world: &mut World) { /// let mut counter = world.get_resource_or_insert_with(Counter::default); /// counter.0 += self.0; /// } /// } /// /// fn add_three_to_counter_system(mut commands: Commands) { /// commands.queue(AddToCounter(3)); /// } /// fn add_twenty_five_to_counter_system(mut commands: Commands) { /// commands.queue(|world: &mut World| { /// let mut counter = world.get_resource_or_insert_with(Counter::default); /// counter.0 += 25; /// }); /// } /// # bevy_ecs::system::assert_is_system(add_three_to_counter_system); /// # bevy_ecs::system::assert_is_system(add_twenty_five_to_counter_system); /// ``` pub fn queue(&mut self, command: C) { match &mut self.queue { InternalQueue::CommandQueue(queue) => { queue.push(command); } InternalQueue::RawCommandQueue(queue) => { // SAFETY: `RawCommandQueue` is only every constructed in `Commands::new_raw_from_entities` // where the caller of that has ensured that `queue` outlives `self` unsafe { queue.push(command); } } } } /// Pushes a [`Command`] to the queue for creating entities, if needed, /// and for adding a bundle to each entity. /// /// `bundles_iter` is a type that can be converted into an ([`Entity`], [`Bundle`]) iterator /// (it can also be a collection). /// /// When the command is applied, /// for each (`Entity`, `Bundle`) pair in the given `bundles_iter`, /// the `Entity` is spawned, if it does not exist already. /// Then, the `Bundle` is added to the entity. /// /// This method is equivalent to iterating `bundles_iter`, /// calling [`get_or_spawn`](Self::get_or_spawn) for each bundle, /// and passing it to [`insert`](EntityCommands::insert), /// but it is faster due to memory pre-allocation. /// /// # Note /// /// Spawning a specific `entity` value is rarely the right choice. Most apps should use [`Commands::spawn_batch`]. /// This method should generally only be used for sharing entities across apps, and only when they have a scheme /// worked out to share an ID space (which doesn't happen by default). #[track_caller] pub fn insert_or_spawn_batch(&mut self, bundles_iter: I) where I: IntoIterator + Send + Sync + 'static, B: Bundle, { self.queue(insert_or_spawn_batch(bundles_iter)); } /// Pushes a [`Command`] to the queue for adding a [`Bundle`] type to a batch of [`Entities`](Entity). /// /// A batch can be any type that implements [`IntoIterator`] containing `(Entity, Bundle)` tuples, /// such as a [`Vec<(Entity, Bundle)>`] or an array `[(Entity, Bundle); N]`. /// /// When the command is applied, for each `(Entity, Bundle)` pair in the given batch, /// the `Bundle` is added to the `Entity`, overwriting any existing components shared by the `Bundle`. /// /// This method is equivalent to iterating the batch, /// calling [`entity`](Self::entity) for each pair, /// and passing the bundle to [`insert`](EntityCommands::insert), /// but it is faster due to memory pre-allocation. /// /// # Panics /// /// This command panics if any of the given entities do not exist. /// /// For the non-panicking version, see [`try_insert_batch`](Self::try_insert_batch). #[track_caller] pub fn insert_batch(&mut self, batch: I) where I: IntoIterator + Send + Sync + 'static, B: Bundle, { self.queue(insert_batch(batch)); } /// Pushes a [`Command`] to the queue for adding a [`Bundle`] type to a batch of [`Entities`](Entity). /// /// A batch can be any type that implements [`IntoIterator`] containing `(Entity, Bundle)` tuples, /// such as a [`Vec<(Entity, Bundle)>`] or an array `[(Entity, Bundle); N]`. /// /// When the command is applied, for each `(Entity, Bundle)` pair in the given batch, /// the `Bundle` is added to the `Entity`, except for any components already present on the `Entity`. /// /// This method is equivalent to iterating the batch, /// calling [`entity`](Self::entity) for each pair, /// and passing the bundle to [`insert_if_new`](EntityCommands::insert_if_new), /// but it is faster due to memory pre-allocation. /// /// # Panics /// /// This command panics if any of the given entities do not exist. /// /// For the non-panicking version, see [`try_insert_batch_if_new`](Self::try_insert_batch_if_new). #[track_caller] pub fn insert_batch_if_new(&mut self, batch: I) where I: IntoIterator + Send + Sync + 'static, B: Bundle, { self.queue(insert_batch_if_new(batch)); } /// Pushes a [`Command`] to the queue for adding a [`Bundle`] type to a batch of [`Entities`](Entity). /// /// A batch can be any type that implements [`IntoIterator`] containing `(Entity, Bundle)` tuples, /// such as a [`Vec<(Entity, Bundle)>`] or an array `[(Entity, Bundle); N]`. /// /// When the command is applied, for each `(Entity, Bundle)` pair in the given batch, /// the `Bundle` is added to the `Entity`, overwriting any existing components shared by the `Bundle`. /// /// This method is equivalent to iterating the batch, /// calling [`get_entity`](Self::get_entity) for each pair, /// and passing the bundle to [`insert`](EntityCommands::insert), /// but it is faster due to memory pre-allocation. /// /// This command silently fails by ignoring any entities that do not exist. /// /// For the panicking version, see [`insert_batch`](Self::insert_batch). #[track_caller] pub fn try_insert_batch(&mut self, batch: I) where I: IntoIterator + Send + Sync + 'static, B: Bundle, { self.queue(try_insert_batch(batch)); } /// Pushes a [`Command`] to the queue for adding a [`Bundle`] type to a batch of [`Entities`](Entity). /// /// A batch can be any type that implements [`IntoIterator`] containing `(Entity, Bundle)` tuples, /// such as a [`Vec<(Entity, Bundle)>`] or an array `[(Entity, Bundle); N]`. /// /// When the command is applied, for each `(Entity, Bundle)` pair in the given batch, /// the `Bundle` is added to the `Entity`, except for any components already present on the `Entity`. /// /// This method is equivalent to iterating the batch, /// calling [`get_entity`](Self::get_entity) for each pair, /// and passing the bundle to [`insert_if_new`](EntityCommands::insert_if_new), /// but it is faster due to memory pre-allocation. /// /// This command silently fails by ignoring any entities that do not exist. /// /// For the panicking version, see [`insert_batch_if_new`](Self::insert_batch_if_new). #[track_caller] pub fn try_insert_batch_if_new(&mut self, batch: I) where I: IntoIterator + Send + Sync + 'static, B: Bundle, { self.queue(try_insert_batch_if_new(batch)); } /// Pushes a [`Command`] to the queue for inserting a [`Resource`] in the [`World`] with an inferred value. /// /// The inferred value is determined by the [`FromWorld`] trait of the resource. /// When the command is applied, /// if the resource already exists, nothing happens. /// /// See [`World::init_resource`] for more details. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// # #[derive(Resource, Default)] /// # struct Scoreboard { /// # current_score: u32, /// # high_score: u32, /// # } /// # /// # fn initialize_scoreboard(mut commands: Commands) { /// commands.init_resource::(); /// # } /// # bevy_ecs::system::assert_is_system(initialize_scoreboard); /// ``` #[track_caller] pub fn init_resource(&mut self) { self.queue(init_resource::); } /// Pushes a [`Command`] to the queue for inserting a [`Resource`] in the [`World`] with a specific value. /// /// This will overwrite any previous value of the same resource type. /// /// See [`World::insert_resource`] for more details. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// # #[derive(Resource)] /// # struct Scoreboard { /// # current_score: u32, /// # high_score: u32, /// # } /// # /// # fn system(mut commands: Commands) { /// commands.insert_resource(Scoreboard { /// current_score: 0, /// high_score: 0, /// }); /// # } /// # bevy_ecs::system::assert_is_system(system); /// ``` #[track_caller] pub fn insert_resource(&mut self, resource: R) { self.queue(insert_resource(resource)); } /// Pushes a [`Command`] to the queue for removing a [`Resource`] from the [`World`]. /// /// See [`World::remove_resource`] for more details. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// # #[derive(Resource)] /// # struct Scoreboard { /// # current_score: u32, /// # high_score: u32, /// # } /// # /// # fn system(mut commands: Commands) { /// commands.remove_resource::(); /// # } /// # bevy_ecs::system::assert_is_system(system); /// ``` pub fn remove_resource(&mut self) { self.queue(remove_resource::); } /// Runs the system corresponding to the given [`SystemId`]. /// Systems are ran in an exclusive and single threaded way. /// Running slow systems can become a bottleneck. /// /// Calls [`World::run_system`](World::run_system). /// /// There is no way to get the output of a system when run as a command, because the /// execution of the system happens later. To get the output of a system, use /// [`World::run_system`] or [`World::run_system_with_input`] instead of running the system as a command. pub fn run_system(&mut self, id: SystemId) { self.run_system_with_input(id, ()); } /// Runs the system corresponding to the given [`SystemId`]. /// Systems are ran in an exclusive and single threaded way. /// Running slow systems can become a bottleneck. /// /// Calls [`World::run_system_with_input`](World::run_system_with_input). /// /// There is no way to get the output of a system when run as a command, because the /// execution of the system happens later. To get the output of a system, use /// [`World::run_system`] or [`World::run_system_with_input`] instead of running the system as a command. pub fn run_system_with_input(&mut self, id: SystemId, input: I::Inner<'static>) where I: SystemInput: Send> + 'static, { self.queue(RunSystemWithInput::new_with_input(id, input)); } /// Registers a system and returns a [`SystemId`] so it can later be called by [`World::run_system`]. /// /// It's possible to register the same systems more than once, they'll be stored separately. /// /// This is different from adding systems to a [`Schedule`](crate::schedule::Schedule), /// because the [`SystemId`] that is returned can be used anywhere in the [`World`] to run the associated system. /// This allows for running systems in a push-based fashion. /// Using a [`Schedule`](crate::schedule::Schedule) is still preferred for most cases /// due to its better performance and ability to run non-conflicting systems simultaneously. /// /// If you want to prevent Commands from registering the same system multiple times, consider using [`Local`](crate::system::Local) /// /// # Example /// /// ``` /// # use bevy_ecs::{prelude::*, world::CommandQueue, system::SystemId}; /// /// #[derive(Resource)] /// struct Counter(i32); /// /// fn register_system(mut local_system: Local>, mut commands: Commands) { /// if let Some(system) = *local_system { /// commands.run_system(system); /// } else { /// *local_system = Some(commands.register_system(increment_counter)); /// } /// } /// /// fn increment_counter(mut value: ResMut) { /// value.0 += 1; /// } /// /// # let mut world = World::default(); /// # world.insert_resource(Counter(0)); /// # let mut queue_1 = CommandQueue::default(); /// # let systemid = { /// # let mut commands = Commands::new(&mut queue_1, &world); /// # commands.register_system(increment_counter) /// # }; /// # let mut queue_2 = CommandQueue::default(); /// # { /// # let mut commands = Commands::new(&mut queue_2, &world); /// # commands.run_system(systemid); /// # } /// # queue_1.append(&mut queue_2); /// # queue_1.apply(&mut world); /// # assert_eq!(1, world.resource::().0); /// # bevy_ecs::system::assert_is_system(register_system); /// ``` pub fn register_system( &mut self, system: impl IntoSystem + 'static, ) -> SystemId where I: SystemInput + Send + 'static, O: Send + 'static, { let entity = self.spawn_empty().id(); self.queue(RegisterSystem::new(system, entity)); SystemId::from_entity(entity) } /// Removes a system previously registered with [`Commands::register_system`] or [`World::register_system`]. /// /// See [`World::unregister_system`] for more information. pub fn unregister_system(&mut self, system_id: SystemId) where I: SystemInput + Send + 'static, O: Send + 'static, { self.queue(UnregisterSystem::new(system_id)); } /// Similar to [`Self::run_system`], but caching the [`SystemId`] in a /// [`CachedSystemId`](crate::system::CachedSystemId) resource. /// /// See [`World::register_system_cached`] for more information. pub fn run_system_cached + Send + 'static>( &mut self, system: S, ) { self.run_system_cached_with(system, ()); } /// Similar to [`Self::run_system_with_input`], but caching the [`SystemId`] in a /// [`CachedSystemId`](crate::system::CachedSystemId) resource. /// /// See [`World::register_system_cached`] for more information. pub fn run_system_cached_with(&mut self, system: S, input: I::Inner<'static>) where I: SystemInput: Send> + Send + 'static, M: 'static, S: IntoSystem + Send + 'static, { self.queue(RunSystemCachedWith::new(system, input)); } /// Sends a "global" [`Trigger`] without any targets. This will run any [`Observer`] of the `event` that /// isn't scoped to specific targets. /// /// [`Trigger`]: crate::observer::Trigger pub fn trigger(&mut self, event: impl Event) { self.queue(TriggerEvent { event, targets: () }); } /// Sends a [`Trigger`] for the given targets. This will run any [`Observer`] of the `event` that /// watches those targets. /// /// [`Trigger`]: crate::observer::Trigger pub fn trigger_targets( &mut self, event: impl Event, targets: impl TriggerTargets + Send + Sync + 'static, ) { self.queue(TriggerEvent { event, targets }); } /// Spawns an [`Observer`] and returns the [`EntityCommands`] associated /// with the entity that stores the observer. /// /// **Calling [`observe`](EntityCommands::observe) on the returned /// [`EntityCommands`] will observe the observer itself, which you very /// likely do not want.** pub fn add_observer( &mut self, observer: impl IntoObserverSystem, ) -> EntityCommands { self.spawn(Observer::new(observer)) } /// Sends an arbitrary [`Event`]. /// /// This is a convenience method for sending events without requiring an [`EventWriter`]. /// ## Performance /// Since this is a command, exclusive world access is used, which means that it will not profit from /// system-level parallelism on supported platforms. /// If these events are performance-critical or very frequently /// sent, consider using a typed [`EventWriter`] instead. /// /// [`EventWriter`]: crate::event::EventWriter pub fn send_event(&mut self, event: E) -> &mut Self { self.queue(SendEvent { event }); self } /// Runs the schedule corresponding to the given [`ScheduleLabel`]. /// /// Calls [`World::try_run_schedule`](World::try_run_schedule). /// /// This will log an error if the schedule is not available to be run. /// /// # Examples /// /// ``` /// # use bevy_ecs::prelude::*; /// # use bevy_ecs::schedule::ScheduleLabel; /// # /// # #[derive(Default, Resource)] /// # struct Counter(u32); /// # /// #[derive(ScheduleLabel, Hash, Debug, PartialEq, Eq, Clone, Copy)] /// struct FooSchedule; /// /// # fn foo_system(mut counter: ResMut) { /// # counter.0 += 1; /// # } /// # /// # let mut schedule = Schedule::new(FooSchedule); /// # schedule.add_systems(foo_system); /// # /// # let mut world = World::default(); /// # /// # world.init_resource::(); /// # world.add_schedule(schedule); /// # /// # assert_eq!(world.resource::().0, 0); /// # /// # let mut commands = world.commands(); /// commands.run_schedule(FooSchedule); /// # /// # world.flush(); /// # /// # assert_eq!(world.resource::().0, 1); /// ``` pub fn run_schedule(&mut self, label: impl ScheduleLabel) { self.queue(|world: &mut World| { if let Err(error) = world.try_run_schedule(label) { panic!("Failed to run schedule: {error}"); } }); } } /// A [`Command`] which gets executed for a given [`Entity`]. /// /// # Examples /// /// ``` /// # use std::collections::HashSet; /// # use bevy_ecs::prelude::*; /// use bevy_ecs::system::EntityCommand; /// # /// # #[derive(Component, PartialEq)] /// # struct Name(String); /// # impl Name { /// # fn new(s: String) -> Self { Name(s) } /// # fn as_str(&self) -> &str { &self.0 } /// # } /// /// #[derive(Resource, Default)] /// struct Counter(i64); /// /// /// A `Command` which names an entity based on a global counter. /// fn count_name(entity: Entity, world: &mut World) { /// // Get the current value of the counter, and increment it for next time. /// let mut counter = world.resource_mut::(); /// let i = counter.0; /// counter.0 += 1; /// /// // Name the entity after the value of the counter. /// world.entity_mut(entity).insert(Name::new(format!("Entity #{i}"))); /// } /// /// // App creation boilerplate omitted... /// # let mut world = World::new(); /// # world.init_resource::(); /// # /// # let mut setup_schedule = Schedule::default(); /// # setup_schedule.add_systems(setup); /// # let mut assert_schedule = Schedule::default(); /// # assert_schedule.add_systems(assert_names); /// # /// # setup_schedule.run(&mut world); /// # assert_schedule.run(&mut world); /// /// fn setup(mut commands: Commands) { /// commands.spawn_empty().queue(count_name); /// commands.spawn_empty().queue(count_name); /// } /// /// fn assert_names(named: Query<&Name>) { /// // We use a HashSet because we do not care about the order. /// let names: HashSet<_> = named.iter().map(Name::as_str).collect(); /// assert_eq!(names, HashSet::from_iter(["Entity #0", "Entity #1"])); /// } /// ``` pub trait EntityCommand: Send + 'static { /// Executes this command for the given [`Entity`]. fn apply(self, entity: Entity, world: &mut World); /// Returns a [`Command`] which executes this [`EntityCommand`] for the given [`Entity`]. /// /// This method is called when adding an [`EntityCommand`] to a command queue via [`Commands`]. /// You can override the provided implementation if you can return a `Command` with a smaller memory /// footprint than `(Entity, Self)`. /// In most cases the provided implementation is sufficient. #[must_use = "commands do nothing unless applied to a `World`"] fn with_entity(self, entity: Entity) -> impl Command where Self: Sized, { move |world: &mut World| self.apply(entity, world) } } /// A list of commands that will be run to modify an [entity](crate::entity). pub struct EntityCommands<'a> { pub(crate) entity: Entity, pub(crate) commands: Commands<'a, 'a>, } impl<'a> EntityCommands<'a> { /// Returns the [`Entity`] id of the entity. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// fn my_system(mut commands: Commands) { /// let entity_id = commands.spawn_empty().id(); /// } /// # bevy_ecs::system::assert_is_system(my_system); /// ``` #[inline] #[must_use = "Omit the .id() call if you do not need to store the `Entity` identifier."] pub fn id(&self) -> Entity { self.entity } /// Returns an [`EntityCommands`] with a smaller lifetime. /// This is useful if you have `&mut EntityCommands` but you need `EntityCommands`. pub fn reborrow(&mut self) -> EntityCommands { EntityCommands { entity: self.entity, commands: self.commands.reborrow(), } } /// Get an [`EntityEntryCommands`] for the [`Component`] `T`, /// allowing you to modify it or insert it if it isn't already present. /// /// See also [`insert_if_new`](Self::insert_if_new), which lets you insert a [`Bundle`] without overwriting it. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # #[derive(Resource)] /// # struct PlayerEntity { entity: Entity } /// #[derive(Component)] /// struct Level(u32); /// /// fn level_up_system(mut commands: Commands, player: Res) { /// commands /// .entity(player.entity) /// .entry::() /// // Modify the component if it exists /// .and_modify(|mut lvl| lvl.0 += 1) /// // Otherwise insert a default value /// .or_insert(Level(0)); /// } /// # bevy_ecs::system::assert_is_system(level_up_system); /// ``` pub fn entry(&mut self) -> EntityEntryCommands { EntityEntryCommands { entity_commands: self.reborrow(), marker: PhantomData, } } /// Adds a [`Bundle`] of components to the entity. /// /// This will overwrite any previous value(s) of the same component type. /// See [`EntityCommands::insert_if_new`] to keep the old value instead. /// /// # Panics /// /// The command will panic when applied if the associated entity does not exist. /// /// To avoid a panic in this case, use the command [`Self::try_insert`] instead. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # #[derive(Resource)] /// # struct PlayerEntity { entity: Entity } /// #[derive(Component)] /// struct Health(u32); /// #[derive(Component)] /// struct Strength(u32); /// #[derive(Component)] /// struct Defense(u32); /// /// #[derive(Bundle)] /// struct CombatBundle { /// health: Health, /// strength: Strength, /// } /// /// fn add_combat_stats_system(mut commands: Commands, player: Res) { /// commands /// .entity(player.entity) /// // You can insert individual components: /// .insert(Defense(10)) /// // You can also insert pre-defined bundles of components: /// .insert(CombatBundle { /// health: Health(100), /// strength: Strength(40), /// }) /// // You can also insert tuples of components and bundles. /// // This is equivalent to the calls above: /// .insert(( /// Defense(10), /// CombatBundle { /// health: Health(100), /// strength: Strength(40), /// }, /// )); /// } /// # bevy_ecs::system::assert_is_system(add_combat_stats_system); /// ``` #[track_caller] pub fn insert(&mut self, bundle: impl Bundle) -> &mut Self { self.queue(insert(bundle, InsertMode::Replace)) } /// Similar to [`Self::insert`] but will only insert if the predicate returns true. /// This is useful for chaining method calls. /// /// # Panics /// /// The command will panic when applied if the associated entity does not exist. /// /// To avoid a panic in this case, use the command [`Self::try_insert_if`] instead. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # #[derive(Resource)] /// # struct PlayerEntity { entity: Entity } /// # impl PlayerEntity { fn is_spectator(&self) -> bool { true } } /// #[derive(Component)] /// struct StillLoadingStats; /// #[derive(Component)] /// struct Health(u32); /// /// fn add_health_system(mut commands: Commands, player: Res) { /// commands /// .entity(player.entity) /// .insert_if(Health(10), || !player.is_spectator()) /// .remove::(); /// } /// # bevy_ecs::system::assert_is_system(add_health_system); /// ``` #[track_caller] pub fn insert_if(&mut self, bundle: impl Bundle, condition: F) -> &mut Self where F: FnOnce() -> bool, { if condition() { self.queue(insert(bundle, InsertMode::Replace)) } else { self } } /// Adds a [`Bundle`] of components to the entity without overwriting. /// /// This is the same as [`EntityCommands::insert`], but in case of duplicate /// components will leave the old values instead of replacing them with new /// ones. /// /// See also [`entry`](Self::entry), which lets you modify a [`Component`] if it's present, /// as well as initialize it with a default value. /// /// # Panics /// /// The command will panic when applied if the associated entity does not exist. /// /// To avoid a panic in this case, use the command [`Self::try_insert_if_new`] instead. pub fn insert_if_new(&mut self, bundle: impl Bundle) -> &mut Self { self.queue(insert(bundle, InsertMode::Keep)) } /// Adds a [`Bundle`] of components to the entity without overwriting if the /// predicate returns true. /// /// This is the same as [`EntityCommands::insert_if`], but in case of duplicate /// components will leave the old values instead of replacing them with new /// ones. /// /// # Panics /// /// The command will panic when applied if the associated entity does not /// exist. /// /// To avoid a panic in this case, use the command [`Self::try_insert_if_new`] /// instead. pub fn insert_if_new_and(&mut self, bundle: impl Bundle, condition: F) -> &mut Self where F: FnOnce() -> bool, { if condition() { self.insert_if_new(bundle) } else { self } } /// Adds a dynamic component to an entity. /// /// See [`EntityWorldMut::insert_by_id`] for more information. /// /// # Panics /// /// The command will panic when applied if the associated entity does not exist. /// /// To avoid a panic in this case, use the command [`Self::try_insert_by_id`] instead. /// /// # Safety /// /// - [`ComponentId`] must be from the same world as `self`. /// - `T` must have the same layout as the one passed during `component_id` creation. #[track_caller] pub unsafe fn insert_by_id( &mut self, component_id: ComponentId, value: T, ) -> &mut Self { let caller = Location::caller(); // SAFETY: same invariants as parent call self.queue(unsafe {insert_by_id(component_id, value, move |entity| { panic!("error[B0003]: {caller}: Could not insert a component {component_id:?} (with type {}) for entity {entity:?} because it doesn't exist in this World. See: https://bevyengine.org/learn/errors/b0003", core::any::type_name::()); })}) } /// Attempts to add a dynamic component to an entity. /// /// See [`EntityWorldMut::insert_by_id`] for more information. /// /// # Safety /// /// - [`ComponentId`] must be from the same world as `self`. /// - `T` must have the same layout as the one passed during `component_id` creation. pub unsafe fn try_insert_by_id( &mut self, component_id: ComponentId, value: T, ) -> &mut Self { // SAFETY: same invariants as parent call self.queue(unsafe { insert_by_id(component_id, value, |_| {}) }) } /// Tries to add a [`Bundle`] of components to the entity. /// /// This will overwrite any previous value(s) of the same component type. /// /// # Note /// /// Unlike [`Self::insert`], this will not panic if the associated entity does not exist. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # #[derive(Resource)] /// # struct PlayerEntity { entity: Entity } /// #[derive(Component)] /// struct Health(u32); /// #[derive(Component)] /// struct Strength(u32); /// #[derive(Component)] /// struct Defense(u32); /// /// #[derive(Bundle)] /// struct CombatBundle { /// health: Health, /// strength: Strength, /// } /// /// fn add_combat_stats_system(mut commands: Commands, player: Res) { /// commands.entity(player.entity) /// // You can try_insert individual components: /// .try_insert(Defense(10)) /// /// // You can also insert tuples of components: /// .try_insert(CombatBundle { /// health: Health(100), /// strength: Strength(40), /// }); /// /// // Suppose this occurs in a parallel adjacent system or process /// commands.entity(player.entity) /// .despawn(); /// /// commands.entity(player.entity) /// // This will not panic nor will it add the component /// .try_insert(Defense(5)); /// } /// # bevy_ecs::system::assert_is_system(add_combat_stats_system); /// ``` #[track_caller] pub fn try_insert(&mut self, bundle: impl Bundle) -> &mut Self { self.queue(try_insert(bundle, InsertMode::Replace)) } /// Similar to [`Self::try_insert`] but will only try to insert if the predicate returns true. /// This is useful for chaining method calls. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # #[derive(Resource)] /// # struct PlayerEntity { entity: Entity } /// # impl PlayerEntity { fn is_spectator(&self) -> bool { true } } /// #[derive(Component)] /// struct StillLoadingStats; /// #[derive(Component)] /// struct Health(u32); /// /// fn add_health_system(mut commands: Commands, player: Res) { /// commands.entity(player.entity) /// .try_insert_if(Health(10), || !player.is_spectator()) /// .remove::(); /// /// commands.entity(player.entity) /// // This will not panic nor will it add the component /// .try_insert_if(Health(5), || !player.is_spectator()); /// } /// # bevy_ecs::system::assert_is_system(add_health_system); /// ``` #[track_caller] pub fn try_insert_if(&mut self, bundle: impl Bundle, condition: F) -> &mut Self where F: FnOnce() -> bool, { if condition() { self.queue(try_insert(bundle, InsertMode::Replace)) } else { self } } /// Tries to add a [`Bundle`] of components to the entity without overwriting if the /// predicate returns true. /// /// This is the same as [`EntityCommands::try_insert_if`], but in case of duplicate /// components will leave the old values instead of replacing them with new /// ones. /// /// # Note /// /// Unlike [`Self::insert_if_new_and`], this will not panic if the associated entity does /// not exist. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # #[derive(Resource)] /// # struct PlayerEntity { entity: Entity } /// # impl PlayerEntity { fn is_spectator(&self) -> bool { true } } /// #[derive(Component)] /// struct StillLoadingStats; /// #[derive(Component)] /// struct Health(u32); /// /// fn add_health_system(mut commands: Commands, player: Res) { /// commands.entity(player.entity) /// .try_insert_if(Health(10), || player.is_spectator()) /// .remove::(); /// /// commands.entity(player.entity) /// // This will not panic nor will it overwrite the component /// .try_insert_if_new_and(Health(5), || player.is_spectator()); /// } /// # bevy_ecs::system::assert_is_system(add_health_system); /// ``` pub fn try_insert_if_new_and(&mut self, bundle: impl Bundle, condition: F) -> &mut Self where F: FnOnce() -> bool, { if condition() { self.try_insert_if_new(bundle) } else { self } } /// Tries to add a [`Bundle`] of components to the entity without overwriting. /// /// This is the same as [`EntityCommands::try_insert`], but in case of duplicate /// components will leave the old values instead of replacing them with new /// ones. /// /// # Note /// /// Unlike [`Self::insert_if_new`], this will not panic if the associated entity does not exist. pub fn try_insert_if_new(&mut self, bundle: impl Bundle) -> &mut Self { self.queue(try_insert(bundle, InsertMode::Keep)) } /// Removes a [`Bundle`] of components from the entity. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// # #[derive(Resource)] /// # struct PlayerEntity { entity: Entity } /// #[derive(Component)] /// struct Health(u32); /// #[derive(Component)] /// struct Strength(u32); /// #[derive(Component)] /// struct Defense(u32); /// /// #[derive(Bundle)] /// struct CombatBundle { /// health: Health, /// strength: Strength, /// } /// /// fn remove_combat_stats_system(mut commands: Commands, player: Res) { /// commands /// .entity(player.entity) /// // You can remove individual components: /// .remove::() /// // You can also remove pre-defined Bundles of components: /// .remove::() /// // You can also remove tuples of components and bundles. /// // This is equivalent to the calls above: /// .remove::<(Defense, CombatBundle)>(); /// } /// # bevy_ecs::system::assert_is_system(remove_combat_stats_system); /// ``` pub fn remove(&mut self) -> &mut Self where T: Bundle, { self.queue(remove::) } /// Removes all components in the [`Bundle`] components and remove all required components for each component in the [`Bundle`] from entity. /// /// # Example /// /// ``` /// use bevy_ecs::prelude::*; /// /// #[derive(Component)] /// #[require(B)] /// struct A; /// #[derive(Component, Default)] /// struct B; /// /// #[derive(Resource)] /// struct PlayerEntity { entity: Entity } /// /// fn remove_with_requires_system(mut commands: Commands, player: Res) { /// commands /// .entity(player.entity) /// // Remove both A and B components from the entity, because B is required by A /// .remove_with_requires::(); /// } /// # bevy_ecs::system::assert_is_system(remove_with_requires_system); /// ``` pub fn remove_with_requires(&mut self) -> &mut Self { self.queue(remove_with_requires::) } /// Removes a component from the entity. pub fn remove_by_id(&mut self, component_id: ComponentId) -> &mut Self { self.queue(remove_by_id(component_id)) } /// Removes all components associated with the entity. pub fn clear(&mut self) -> &mut Self { self.queue(clear()) } /// Despawns the entity. /// This will emit a warning if the entity does not exist. /// /// See [`World::despawn`] for more details. /// /// # Note /// /// This won't clean up external references to the entity (such as parent-child relationships /// if you're using `bevy_hierarchy`), which may leave the world in an invalid state. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// # #[derive(Resource)] /// # struct CharacterToRemove { entity: Entity } /// # /// fn remove_character_system( /// mut commands: Commands, /// character_to_remove: Res /// ) /// { /// commands.entity(character_to_remove.entity).despawn(); /// } /// # bevy_ecs::system::assert_is_system(remove_character_system); /// ``` #[track_caller] pub fn despawn(&mut self) { self.queue(despawn()); } /// Despawns the entity. /// This will not emit a warning if the entity does not exist, essentially performing /// the same function as [`Self::despawn`] without emitting warnings. #[track_caller] pub fn try_despawn(&mut self) { self.queue(try_despawn()); } /// Pushes an [`EntityCommand`] to the queue, which will get executed for the current [`Entity`]. /// /// # Examples /// /// ``` /// # use bevy_ecs::prelude::*; /// # fn my_system(mut commands: Commands) { /// commands /// .spawn_empty() /// // Closures with this signature implement `EntityCommand`. /// .queue(|entity: EntityWorldMut| { /// println!("Executed an EntityCommand for {:?}", entity.id()); /// }); /// # } /// # bevy_ecs::system::assert_is_system(my_system); /// ``` pub fn queue(&mut self, command: impl EntityCommand) -> &mut Self { self.commands.queue(command.with_entity(self.entity)); self } /// Removes all components except the given [`Bundle`] from the entity. /// /// This can also be used to remove all the components from the entity by passing it an empty Bundle. /// /// # Example /// /// ``` /// # use bevy_ecs::prelude::*; /// # /// # #[derive(Resource)] /// # struct PlayerEntity { entity: Entity } /// #[derive(Component)] /// struct Health(u32); /// #[derive(Component)] /// struct Strength(u32); /// #[derive(Component)] /// struct Defense(u32); /// /// #[derive(Bundle)] /// struct CombatBundle { /// health: Health, /// strength: Strength, /// } /// /// fn remove_combat_stats_system(mut commands: Commands, player: Res) { /// commands /// .entity(player.entity) /// // You can retain a pre-defined Bundle of components, /// // with this removing only the Defense component /// .retain::() /// // You can also retain only a single component /// .retain::() /// // And you can remove all the components by passing in an empty Bundle /// .retain::<()>(); /// } /// # bevy_ecs::system::assert_is_system(remove_combat_stats_system); /// ``` pub fn retain(&mut self) -> &mut Self where T: Bundle, { self.queue(retain::) } /// Logs the components of the entity at the info level. /// /// # Panics /// /// The command will panic when applied if the associated entity does not exist. pub fn log_components(&mut self) -> &mut Self { self.queue(log_components) } /// Returns the underlying [`Commands`]. pub fn commands(&mut self) -> Commands { self.commands.reborrow() } /// Returns a mutable reference to the underlying [`Commands`]. pub fn commands_mut(&mut self) -> &mut Commands<'a, 'a> { &mut self.commands } /// Sends a [`Trigger`] targeting this entity. This will run any [`Observer`] of the `event` that /// watches this entity. /// /// [`Trigger`]: crate::observer::Trigger pub fn trigger(&mut self, event: impl Event) -> &mut Self { self.commands.trigger_targets(event, self.entity); self } /// Creates an [`Observer`] listening for a trigger of type `T` that targets this entity. pub fn observe( &mut self, system: impl IntoObserverSystem, ) -> &mut Self { self.queue(observe(system)) } } /// A wrapper around [`EntityCommands`] with convenience methods for working with a specified component type. pub struct EntityEntryCommands<'a, T> { entity_commands: EntityCommands<'a>, marker: PhantomData, } impl<'a, T: Component> EntityEntryCommands<'a, T> { /// Modify the component `T` if it exists, using the function `modify`. pub fn and_modify(&mut self, modify: impl FnOnce(Mut) + Send + Sync + 'static) -> &mut Self { self.entity_commands .queue(move |mut entity: EntityWorldMut| { if let Some(value) = entity.get_mut() { modify(value); } }); self } } impl<'a, T: Component> EntityEntryCommands<'a, T> { /// [Insert](EntityCommands::insert) `default` into this entity, if `T` is not already present. /// /// See also [`or_insert_with`](Self::or_insert_with). /// /// # Panics /// /// Panics if the entity does not exist. /// See [`or_try_insert`](Self::or_try_insert) for a non-panicking version. #[track_caller] pub fn or_insert(&mut self, default: T) -> &mut Self { self.entity_commands .queue(insert(default, InsertMode::Keep)); self } /// [Insert](EntityCommands::insert) `default` into this entity, if `T` is not already present. /// /// Unlike [`or_insert`](Self::or_insert), this will not panic if the entity does not exist. /// /// See also [`or_insert_with`](Self::or_insert_with). #[track_caller] pub fn or_try_insert(&mut self, default: T) -> &mut Self { self.entity_commands .queue(try_insert(default, InsertMode::Keep)); self } /// [Insert](EntityCommands::insert) the value returned from `default` into this entity, if `T` is not already present. /// /// See also [`or_insert`](Self::or_insert) and [`or_try_insert`](Self::or_try_insert). /// /// # Panics /// /// Panics if the entity does not exist. /// See [`or_try_insert_with`](Self::or_try_insert_with) for a non-panicking version. #[track_caller] pub fn or_insert_with(&mut self, default: impl Fn() -> T) -> &mut Self { self.or_insert(default()) } /// [Insert](EntityCommands::insert) the value returned from `default` into this entity, if `T` is not already present. /// /// Unlike [`or_insert_with`](Self::or_insert_with), this will not panic if the entity does not exist. /// /// See also [`or_insert`](Self::or_insert) and [`or_try_insert`](Self::or_try_insert). #[track_caller] pub fn or_try_insert_with(&mut self, default: impl Fn() -> T) -> &mut Self { self.or_try_insert(default()) } /// [Insert](EntityCommands::insert) `T::default` into this entity, if `T` is not already present. /// /// See also [`or_insert`](Self::or_insert) and [`or_from_world`](Self::or_from_world). /// /// # Panics /// /// Panics if the entity does not exist. #[track_caller] pub fn or_default(&mut self) -> &mut Self where T: Default, { #[allow(clippy::unwrap_or_default)] // FIXME: use `expect` once stable self.or_insert(T::default()) } /// [Insert](EntityCommands::insert) `T::from_world` into this entity, if `T` is not already present. /// /// See also [`or_insert`](Self::or_insert) and [`or_default`](Self::or_default). /// /// # Panics /// /// Panics if the entity does not exist. #[track_caller] pub fn or_from_world(&mut self) -> &mut Self where T: FromWorld, { self.entity_commands .queue(insert_from_world::(InsertMode::Keep)); self } } impl Command for F where F: FnOnce(&mut World) + Send + 'static, { fn apply(self, world: &mut World) { self(world); } } impl EntityCommand for F where F: FnOnce(EntityWorldMut) + Send + 'static, { fn apply(self, id: Entity, world: &mut World) { self(world.entity_mut(id)); } } impl EntityCommand for F where F: FnOnce(Entity, &mut World) + Send + 'static, { fn apply(self, id: Entity, world: &mut World) { self(id, world); } } /// A [`Command`] that consumes an iterator of [`Bundle`]s to spawn a series of entities. /// /// This is more efficient than spawning the entities individually. #[track_caller] fn spawn_batch(bundles_iter: I) -> impl Command where I: IntoIterator + Send + Sync + 'static, B: Bundle, { #[cfg(feature = "track_change_detection")] let caller = Location::caller(); move |world: &mut World| { SpawnBatchIter::new( world, bundles_iter.into_iter(), #[cfg(feature = "track_change_detection")] caller, ); } } /// A [`Command`] that consumes an iterator to add a series of [`Bundle`]s to a set of entities. /// If any entities do not already exist in the world, they will be spawned. /// /// This is more efficient than inserting the bundles individually. #[track_caller] fn insert_or_spawn_batch(bundles_iter: I) -> impl Command where I: IntoIterator + Send + Sync + 'static, B: Bundle, { #[cfg(feature = "track_change_detection")] let caller = Location::caller(); move |world: &mut World| { if let Err(invalid_entities) = world.insert_or_spawn_batch_with_caller( bundles_iter, #[cfg(feature = "track_change_detection")] caller, ) { error!( "Failed to 'insert or spawn' bundle of type {} into the following invalid entities: {:?}", core::any::type_name::(), invalid_entities ); } } } /// A [`Command`] that consumes an iterator to add a series of [`Bundles`](Bundle) to a set of entities. /// If any entities do not exist in the world, this command will panic. /// /// This is more efficient than inserting the bundles individually. #[track_caller] fn insert_batch(batch: I) -> impl Command where I: IntoIterator + Send + Sync + 'static, B: Bundle, { #[cfg(feature = "track_change_detection")] let caller = Location::caller(); move |world: &mut World| { world.insert_batch_with_caller( batch, InsertMode::Replace, #[cfg(feature = "track_change_detection")] caller, ); } } /// A [`Command`] that consumes an iterator to add a series of [`Bundles`](Bundle) to a set of entities. /// If any entities do not exist in the world, this command will panic. /// /// This is more efficient than inserting the bundles individually. #[track_caller] fn insert_batch_if_new(batch: I) -> impl Command where I: IntoIterator + Send + Sync + 'static, B: Bundle, { #[cfg(feature = "track_change_detection")] let caller = Location::caller(); move |world: &mut World| { world.insert_batch_with_caller( batch, InsertMode::Keep, #[cfg(feature = "track_change_detection")] caller, ); } } /// A [`Command`] that consumes an iterator to add a series of [`Bundles`](Bundle) to a set of entities. /// If any entities do not exist in the world, this command will ignore them. /// /// This is more efficient than inserting the bundles individually. #[track_caller] fn try_insert_batch(batch: I) -> impl Command where I: IntoIterator + Send + Sync + 'static, B: Bundle, { #[cfg(feature = "track_change_detection")] let caller = Location::caller(); move |world: &mut World| { world.try_insert_batch_with_caller( batch, InsertMode::Replace, #[cfg(feature = "track_change_detection")] caller, ); } } /// A [`Command`] that consumes an iterator to add a series of [`Bundles`](Bundle) to a set of entities. /// If any entities do not exist in the world, this command will ignore them. /// /// This is more efficient than inserting the bundles individually. #[track_caller] fn try_insert_batch_if_new(batch: I) -> impl Command where I: IntoIterator + Send + Sync + 'static, B: Bundle, { #[cfg(feature = "track_change_detection")] let caller = Location::caller(); move |world: &mut World| { world.try_insert_batch_with_caller( batch, InsertMode::Keep, #[cfg(feature = "track_change_detection")] caller, ); } } /// A [`Command`] that despawns a specific entity. /// This will emit a warning if the entity does not exist. /// /// # Note /// /// This won't clean up external references to the entity (such as parent-child relationships /// if you're using `bevy_hierarchy`), which may leave the world in an invalid state. #[track_caller] fn despawn() -> impl EntityCommand { let caller = Location::caller(); move |entity: Entity, world: &mut World| { world.despawn_with_caller(entity, caller, true); } } /// A [`Command`] that despawns a specific entity. /// This will not emit a warning if the entity does not exist. /// /// # Note /// /// This won't clean up external references to the entity (such as parent-child relationships /// if you're using `bevy_hierarchy`), which may leave the world in an invalid state. #[track_caller] fn try_despawn() -> impl EntityCommand { let caller = Location::caller(); move |entity: Entity, world: &mut World| { world.despawn_with_caller(entity, caller, false); } } /// An [`EntityCommand`] that adds the components in a [`Bundle`] to an entity. #[track_caller] fn insert(bundle: T, mode: InsertMode) -> impl EntityCommand { let caller = Location::caller(); move |entity: Entity, world: &mut World| { if let Ok(mut entity) = world.get_entity_mut(entity) { entity.insert_with_caller( bundle, mode, #[cfg(feature = "track_change_detection")] caller, ); } else { panic!("error[B0003]: {caller}: Could not insert a bundle (of type `{}`) for entity {:?} because it doesn't exist in this World. See: https://bevyengine.org/learn/errors/b0003", core::any::type_name::(), entity); } } } /// An [`EntityCommand`] that adds the component using its `FromWorld` implementation. #[track_caller] fn insert_from_world(mode: InsertMode) -> impl EntityCommand { let caller = Location::caller(); move |entity: Entity, world: &mut World| { let value = T::from_world(world); if let Ok(mut entity) = world.get_entity_mut(entity) { entity.insert_with_caller( value, mode, #[cfg(feature = "track_change_detection")] caller, ); } else { panic!("error[B0003]: {caller}: Could not insert a bundle (of type `{}`) for entity {:?} because it doesn't exist in this World. See: https://bevyengine.org/learn/errors/b0003", core::any::type_name::(), entity); } } } /// An [`EntityCommand`] that attempts to add the components in a [`Bundle`] to an entity. /// Does nothing if the entity does not exist. #[track_caller] fn try_insert(bundle: impl Bundle, mode: InsertMode) -> impl EntityCommand { #[cfg(feature = "track_change_detection")] let caller = Location::caller(); move |entity: Entity, world: &mut World| { if let Ok(mut entity) = world.get_entity_mut(entity) { entity.insert_with_caller( bundle, mode, #[cfg(feature = "track_change_detection")] caller, ); } } } /// An [`EntityCommand`] that attempts to add the dynamic component to an entity. /// /// # Safety /// /// - The returned `EntityCommand` must be queued for the world where `component_id` was created. /// - `T` must be the type represented by `component_id`. unsafe fn insert_by_id( component_id: ComponentId, value: T, on_none_entity: impl FnOnce(Entity) + Send + 'static, ) -> impl EntityCommand { move |entity: Entity, world: &mut World| { if let Ok(mut entity) = world.get_entity_mut(entity) { // SAFETY: // - `component_id` safety is ensured by the caller // - `ptr` is valid within the `make` block; OwningPtr::make(value, |ptr| unsafe { entity.insert_by_id(component_id, ptr); }); } else { on_none_entity(entity); } } } /// An [`EntityCommand`] that removes components from an entity. /// /// For a [`Bundle`] type `T`, this will remove any components in the bundle. /// Any components in the bundle that aren't found on the entity will be ignored. fn remove(entity: Entity, world: &mut World) { if let Ok(mut entity) = world.get_entity_mut(entity) { entity.remove::(); } } /// An [`EntityCommand`] that removes components with a provided [`ComponentId`] from an entity. /// # Panics /// /// Panics if the provided [`ComponentId`] does not exist in the [`World`]. fn remove_by_id(component_id: ComponentId) -> impl EntityCommand { move |entity: Entity, world: &mut World| { if let Ok(mut entity) = world.get_entity_mut(entity) { entity.remove_by_id(component_id); } } } /// An [`EntityCommand`] that remove all components in the bundle and remove all required components for each component in the bundle. fn remove_with_requires(entity: Entity, world: &mut World) { if let Ok(mut entity) = world.get_entity_mut(entity) { entity.remove_with_requires::(); } } /// An [`EntityCommand`] that removes all components associated with a provided entity. fn clear() -> impl EntityCommand { move |entity: Entity, world: &mut World| { if let Ok(mut entity) = world.get_entity_mut(entity) { entity.clear(); } } } /// An [`EntityCommand`] that removes components from an entity. /// /// For a [`Bundle`] type `T`, this will remove all components except those in the bundle. /// Any components in the bundle that aren't found on the entity will be ignored. fn retain(entity: Entity, world: &mut World) { if let Ok(mut entity_mut) = world.get_entity_mut(entity) { entity_mut.retain::(); } } /// A [`Command`] that inserts a [`Resource`] into the world using a value /// created with the [`FromWorld`] trait. #[track_caller] fn init_resource(world: &mut World) { world.init_resource::(); } /// A [`Command`] that removes the [resource](Resource) `R` from the world. #[track_caller] fn remove_resource(world: &mut World) { world.remove_resource::(); } /// A [`Command`] that inserts a [`Resource`] into the world. #[track_caller] fn insert_resource(resource: R) -> impl Command { #[cfg(feature = "track_change_detection")] let caller = Location::caller(); move |world: &mut World| { world.insert_resource_with_caller( resource, #[cfg(feature = "track_change_detection")] caller, ); } } /// [`EntityCommand`] to log the components of a given entity. See [`EntityCommands::log_components`]. fn log_components(entity: Entity, world: &mut World) { let debug_infos: Vec<_> = world .inspect_entity(entity) .map(ComponentInfo::name) .collect(); info!("Entity {entity}: {debug_infos:?}"); } fn observe( observer: impl IntoObserverSystem, ) -> impl EntityCommand { move |entity: Entity, world: &mut World| { if let Ok(mut entity) = world.get_entity_mut(entity) { entity.observe(observer); } } } #[cfg(test)] #[allow(clippy::float_cmp, clippy::approx_constant)] mod tests { use crate::{ self as bevy_ecs, component::{require, Component}, system::{Commands, Resource}, world::{CommandQueue, FromWorld, World}, }; use alloc::sync::Arc; use core::{ any::TypeId, sync::atomic::{AtomicUsize, Ordering}, }; #[allow(dead_code)] #[derive(Component)] #[component(storage = "SparseSet")] struct SparseDropCk(DropCk); #[derive(Component)] struct DropCk(Arc); impl DropCk { fn new_pair() -> (Self, Arc) { let atomic = Arc::new(AtomicUsize::new(0)); (DropCk(atomic.clone()), atomic) } } impl Drop for DropCk { fn drop(&mut self) { self.0.as_ref().fetch_add(1, Ordering::Relaxed); } } #[derive(Component, Resource)] struct W(T); fn simple_command(world: &mut World) { world.spawn((W(0u32), W(42u64))); } impl FromWorld for W { fn from_world(world: &mut World) -> Self { let v = world.resource::>(); Self("*".repeat(v.0)) } } #[test] fn entity_commands_entry() { let mut world = World::default(); let mut queue = CommandQueue::default(); let mut commands = Commands::new(&mut queue, &world); let entity = commands.spawn_empty().id(); commands .entity(entity) .entry::>() .and_modify(|_| unreachable!()); queue.apply(&mut world); assert!(!world.entity(entity).contains::>()); let mut commands = Commands::new(&mut queue, &world); commands .entity(entity) .entry::>() .or_insert(W(0)) .and_modify(|mut val| { val.0 = 21; }); queue.apply(&mut world); assert_eq!(21, world.get::>(entity).unwrap().0); let mut commands = Commands::new(&mut queue, &world); commands .entity(entity) .entry::>() .and_modify(|_| unreachable!()) .or_insert(W(42)); queue.apply(&mut world); assert_eq!(42, world.get::>(entity).unwrap().0); world.insert_resource(W(5_usize)); let mut commands = Commands::new(&mut queue, &world); commands.entity(entity).entry::>().or_from_world(); queue.apply(&mut world); assert_eq!("*****", &world.get::>(entity).unwrap().0); } #[test] fn commands() { let mut world = World::default(); let mut command_queue = CommandQueue::default(); let entity = Commands::new(&mut command_queue, &world) .spawn((W(1u32), W(2u64))) .id(); command_queue.apply(&mut world); assert_eq!(world.entities().len(), 1); let results = world .query::<(&W, &W)>() .iter(&world) .map(|(a, b)| (a.0, b.0)) .collect::>(); assert_eq!(results, vec![(1u32, 2u64)]); // test entity despawn { let mut commands = Commands::new(&mut command_queue, &world); commands.entity(entity).despawn(); commands.entity(entity).despawn(); // double despawn shouldn't panic } command_queue.apply(&mut world); let results2 = world .query::<(&W, &W)>() .iter(&world) .map(|(a, b)| (a.0, b.0)) .collect::>(); assert_eq!(results2, vec![]); // test adding simple (FnOnce) commands { let mut commands = Commands::new(&mut command_queue, &world); // set up a simple command using a closure that adds one additional entity commands.queue(|world: &mut World| { world.spawn((W(42u32), W(0u64))); }); // set up a simple command using a function that adds one additional entity commands.queue(simple_command); } command_queue.apply(&mut world); let results3 = world .query::<(&W, &W)>() .iter(&world) .map(|(a, b)| (a.0, b.0)) .collect::>(); assert_eq!(results3, vec![(42u32, 0u64), (0u32, 42u64)]); } #[test] fn insert_components() { let mut world = World::default(); let mut command_queue1 = CommandQueue::default(); // insert components let entity = Commands::new(&mut command_queue1, &world) .spawn(()) .insert_if(W(1u8), || true) .insert_if(W(2u8), || false) .insert_if_new(W(1u16)) .insert_if_new(W(2u16)) .insert_if_new_and(W(1u32), || false) .insert_if_new_and(W(2u32), || true) .insert_if_new_and(W(3u32), || true) .id(); command_queue1.apply(&mut world); let results = world .query::<(&W, &W, &W)>() .iter(&world) .map(|(a, b, c)| (a.0, b.0, c.0)) .collect::>(); assert_eq!(results, vec![(1u8, 1u16, 2u32)]); // try to insert components after despawning entity // in another command queue Commands::new(&mut command_queue1, &world) .entity(entity) .try_insert_if_new_and(W(1u64), || true); let mut command_queue2 = CommandQueue::default(); Commands::new(&mut command_queue2, &world) .entity(entity) .despawn(); command_queue2.apply(&mut world); command_queue1.apply(&mut world); } #[test] fn remove_components() { let mut world = World::default(); let mut command_queue = CommandQueue::default(); let (dense_dropck, dense_is_dropped) = DropCk::new_pair(); let (sparse_dropck, sparse_is_dropped) = DropCk::new_pair(); let sparse_dropck = SparseDropCk(sparse_dropck); let entity = Commands::new(&mut command_queue, &world) .spawn((W(1u32), W(2u64), dense_dropck, sparse_dropck)) .id(); command_queue.apply(&mut world); let results_before = world .query::<(&W, &W)>() .iter(&world) .map(|(a, b)| (a.0, b.0)) .collect::>(); assert_eq!(results_before, vec![(1u32, 2u64)]); // test component removal Commands::new(&mut command_queue, &world) .entity(entity) .remove::>() .remove::<(W, W, SparseDropCk, DropCk)>(); assert_eq!(dense_is_dropped.load(Ordering::Relaxed), 0); assert_eq!(sparse_is_dropped.load(Ordering::Relaxed), 0); command_queue.apply(&mut world); assert_eq!(dense_is_dropped.load(Ordering::Relaxed), 1); assert_eq!(sparse_is_dropped.load(Ordering::Relaxed), 1); let results_after = world .query::<(&W, &W)>() .iter(&world) .map(|(a, b)| (a.0, b.0)) .collect::>(); assert_eq!(results_after, vec![]); let results_after_u64 = world .query::<&W>() .iter(&world) .map(|v| v.0) .collect::>(); assert_eq!(results_after_u64, vec![]); } #[test] fn remove_components_by_id() { let mut world = World::default(); let mut command_queue = CommandQueue::default(); let (dense_dropck, dense_is_dropped) = DropCk::new_pair(); let (sparse_dropck, sparse_is_dropped) = DropCk::new_pair(); let sparse_dropck = SparseDropCk(sparse_dropck); let entity = Commands::new(&mut command_queue, &world) .spawn((W(1u32), W(2u64), dense_dropck, sparse_dropck)) .id(); command_queue.apply(&mut world); let results_before = world .query::<(&W, &W)>() .iter(&world) .map(|(a, b)| (a.0, b.0)) .collect::>(); assert_eq!(results_before, vec![(1u32, 2u64)]); // test component removal Commands::new(&mut command_queue, &world) .entity(entity) .remove_by_id(world.components().get_id(TypeId::of::>()).unwrap()) .remove_by_id(world.components().get_id(TypeId::of::>()).unwrap()) .remove_by_id(world.components().get_id(TypeId::of::()).unwrap()) .remove_by_id( world .components() .get_id(TypeId::of::()) .unwrap(), ); assert_eq!(dense_is_dropped.load(Ordering::Relaxed), 0); assert_eq!(sparse_is_dropped.load(Ordering::Relaxed), 0); command_queue.apply(&mut world); assert_eq!(dense_is_dropped.load(Ordering::Relaxed), 1); assert_eq!(sparse_is_dropped.load(Ordering::Relaxed), 1); let results_after = world .query::<(&W, &W)>() .iter(&world) .map(|(a, b)| (a.0, b.0)) .collect::>(); assert_eq!(results_after, vec![]); let results_after_u64 = world .query::<&W>() .iter(&world) .map(|v| v.0) .collect::>(); assert_eq!(results_after_u64, vec![]); } #[test] fn remove_resources() { let mut world = World::default(); let mut queue = CommandQueue::default(); { let mut commands = Commands::new(&mut queue, &world); commands.insert_resource(W(123i32)); commands.insert_resource(W(456.0f64)); } queue.apply(&mut world); assert!(world.contains_resource::>()); assert!(world.contains_resource::>()); { let mut commands = Commands::new(&mut queue, &world); // test resource removal commands.remove_resource::>(); } queue.apply(&mut world); assert!(!world.contains_resource::>()); assert!(world.contains_resource::>()); } #[test] fn remove_component_with_required_components() { #[derive(Component)] #[require(Y)] struct X; #[derive(Component, Default)] struct Y; #[derive(Component)] struct Z; let mut world = World::default(); let mut queue = CommandQueue::default(); let e = { let mut commands = Commands::new(&mut queue, &world); commands.spawn((X, Z)).id() }; queue.apply(&mut world); assert!(world.get::(e).is_some()); assert!(world.get::(e).is_some()); assert!(world.get::(e).is_some()); { let mut commands = Commands::new(&mut queue, &world); commands.entity(e).remove_with_requires::(); } queue.apply(&mut world); assert!(world.get::(e).is_none()); assert!(world.get::(e).is_none()); assert!(world.get::(e).is_some()); } fn is_send() {} fn is_sync() {} #[test] fn test_commands_are_send_and_sync() { is_send::(); is_sync::(); } #[test] fn append() { let mut world = World::default(); let mut queue_1 = CommandQueue::default(); { let mut commands = Commands::new(&mut queue_1, &world); commands.insert_resource(W(123i32)); } let mut queue_2 = CommandQueue::default(); { let mut commands = Commands::new(&mut queue_2, &world); commands.insert_resource(W(456.0f64)); } queue_1.append(&mut queue_2); queue_1.apply(&mut world); assert!(world.contains_resource::>()); assert!(world.contains_resource::>()); } }