1140 lines
39 KiB
Rust
1140 lines
39 KiB
Rust
use crate::{Children, HierarchyEvent, Parent};
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use bevy_ecs::{
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bundle::Bundle,
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entity::Entity,
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prelude::Events,
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system::{Command, Commands, EntityCommands},
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world::{EntityWorldMut, World},
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};
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use smallvec::SmallVec;
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// Do not use `world.send_event_batch` as it prints error message when the Events are not available in the world,
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// even though it's a valid use case to execute commands on a world without events. Loading a GLTF file for example
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fn push_events(world: &mut World, events: impl IntoIterator<Item = HierarchyEvent>) {
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if let Some(mut moved) = world.get_resource_mut::<Events<HierarchyEvent>>() {
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moved.extend(events);
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}
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}
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/// Adds `child` to `parent`'s [`Children`], without checking if it is already present there.
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///
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/// This might cause unexpected results when removing duplicate children.
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fn push_child_unchecked(world: &mut World, parent: Entity, child: Entity) {
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let mut parent = world.entity_mut(parent);
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if let Some(mut children) = parent.get_mut::<Children>() {
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children.0.push(child);
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} else {
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parent.insert(Children(smallvec::smallvec![child]));
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}
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}
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/// Sets [`Parent`] of the `child` to `new_parent`. Inserts [`Parent`] if `child` doesn't have one.
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fn update_parent(world: &mut World, child: Entity, new_parent: Entity) -> Option<Entity> {
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let mut child = world.entity_mut(child);
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if let Some(mut parent) = child.get_mut::<Parent>() {
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let previous = parent.0;
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*parent = Parent(new_parent);
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Some(previous)
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} else {
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child.insert(Parent(new_parent));
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None
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}
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}
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/// Remove child from the parent's [`Children`] component.
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///
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/// Removes the [`Children`] component from the parent if it's empty.
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fn remove_from_children(world: &mut World, parent: Entity, child: Entity) {
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let Some(mut parent) = world.get_entity_mut(parent) else {
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return;
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};
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let Some(mut children) = parent.get_mut::<Children>() else {
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return;
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};
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children.0.retain(|x| *x != child);
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if children.is_empty() {
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parent.remove::<Children>();
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}
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}
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/// Update the [`Parent`] component of the `child`.
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/// Removes the `child` from the previous parent's [`Children`].
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///
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/// Does not update the new parents [`Children`] component.
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///
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/// Does nothing if `child` was already a child of `parent`.
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///
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/// Sends [`HierarchyEvent`]'s.
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fn update_old_parent(world: &mut World, child: Entity, parent: Entity) {
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let previous = update_parent(world, child, parent);
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if let Some(previous_parent) = previous {
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// Do nothing if the child was already parented to this entity.
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if previous_parent == parent {
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return;
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}
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remove_from_children(world, previous_parent, child);
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push_events(
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world,
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[HierarchyEvent::ChildMoved {
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child,
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previous_parent,
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new_parent: parent,
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}],
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);
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} else {
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push_events(world, [HierarchyEvent::ChildAdded { child, parent }]);
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}
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}
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/// Update the [`Parent`] components of the `children`.
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/// Removes the `children` from their previous parent's [`Children`].
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///
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/// Does not update the new parents [`Children`] component.
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///
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/// Does nothing for a child if it was already a child of `parent`.
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///
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/// Sends [`HierarchyEvent`]'s.
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fn update_old_parents(world: &mut World, parent: Entity, children: &[Entity]) {
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let mut events: SmallVec<[HierarchyEvent; 8]> = SmallVec::with_capacity(children.len());
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for &child in children {
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if let Some(previous) = update_parent(world, child, parent) {
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// Do nothing if the entity already has the correct parent.
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if parent == previous {
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continue;
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}
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remove_from_children(world, previous, child);
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events.push(HierarchyEvent::ChildMoved {
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child,
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previous_parent: previous,
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new_parent: parent,
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});
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} else {
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events.push(HierarchyEvent::ChildAdded { child, parent });
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}
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}
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push_events(world, events);
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}
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/// Removes entities in `children` from `parent`'s [`Children`], removing the component if it ends up empty.
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/// Also removes [`Parent`] component from `children`.
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fn remove_children(parent: Entity, children: &[Entity], world: &mut World) {
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let mut events: SmallVec<[HierarchyEvent; 8]> = SmallVec::new();
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if let Some(parent_children) = world.get::<Children>(parent) {
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for &child in children {
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if parent_children.contains(&child) {
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events.push(HierarchyEvent::ChildRemoved { child, parent });
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}
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}
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} else {
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return;
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}
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for event in &events {
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if let &HierarchyEvent::ChildRemoved { child, .. } = event {
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world.entity_mut(child).remove::<Parent>();
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}
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}
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push_events(world, events);
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let mut parent = world.entity_mut(parent);
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if let Some(mut parent_children) = parent.get_mut::<Children>() {
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parent_children
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.0
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.retain(|parent_child| !children.contains(parent_child));
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if parent_children.is_empty() {
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parent.remove::<Children>();
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}
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}
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}
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/// Removes all children from `parent` by removing its [`Children`] component, as well as removing
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/// [`Parent`] component from its children.
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fn clear_children(parent: Entity, world: &mut World) {
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if let Some(children) = world.entity_mut(parent).take::<Children>() {
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for &child in &children.0 {
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world.entity_mut(child).remove::<Parent>();
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}
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}
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}
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/// Command that adds a child to an entity.
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#[derive(Debug)]
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pub struct AddChild {
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/// Parent entity to add the child to.
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pub parent: Entity,
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/// Child entity to add.
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pub child: Entity,
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}
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impl Command for AddChild {
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fn apply(self, world: &mut World) {
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world.entity_mut(self.parent).add_child(self.child);
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}
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}
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/// Command that inserts a child at a given index of a parent's children, shifting following children back.
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#[derive(Debug)]
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pub struct InsertChildren {
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parent: Entity,
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children: SmallVec<[Entity; 8]>,
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index: usize,
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}
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impl Command for InsertChildren {
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fn apply(self, world: &mut World) {
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world
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.entity_mut(self.parent)
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.insert_children(self.index, &self.children);
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}
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}
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/// Command that pushes children to the end of the entity's [`Children`].
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#[derive(Debug)]
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pub struct PushChildren {
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parent: Entity,
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children: SmallVec<[Entity; 8]>,
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}
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impl Command for PushChildren {
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fn apply(self, world: &mut World) {
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world.entity_mut(self.parent).push_children(&self.children);
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}
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}
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/// Command that removes children from an entity, and removes these children's parent.
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pub struct RemoveChildren {
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parent: Entity,
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children: SmallVec<[Entity; 8]>,
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}
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impl Command for RemoveChildren {
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fn apply(self, world: &mut World) {
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remove_children(self.parent, &self.children, world);
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}
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}
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/// Command that clears all children from an entity and removes [`Parent`] component from those
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/// children.
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pub struct ClearChildren {
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parent: Entity,
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}
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impl Command for ClearChildren {
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fn apply(self, world: &mut World) {
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clear_children(self.parent, world);
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}
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}
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/// Command that clear all children from an entity, replacing them with the given children.
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pub struct ReplaceChildren {
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parent: Entity,
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children: SmallVec<[Entity; 8]>,
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}
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impl Command for ReplaceChildren {
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fn apply(self, world: &mut World) {
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clear_children(self.parent, world);
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world.entity_mut(self.parent).push_children(&self.children);
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}
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}
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/// Command that removes the parent of an entity, and removes that entity from the parent's [`Children`].
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pub struct RemoveParent {
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/// `Entity` whose parent must be removed.
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pub child: Entity,
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}
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impl Command for RemoveParent {
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fn apply(self, world: &mut World) {
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world.entity_mut(self.child).remove_parent();
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}
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}
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/// Struct for building children entities and adding them to a parent entity.
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pub struct ChildBuilder<'w, 's, 'a> {
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commands: &'a mut Commands<'w, 's>,
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push_children: PushChildren,
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}
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impl<'w, 's, 'a> ChildBuilder<'w, 's, 'a> {
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/// Spawns an entity with the given bundle and inserts it into the parent entity's [`Children`].
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/// Also adds [`Parent`] component to the created entity.
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pub fn spawn(&mut self, bundle: impl Bundle) -> EntityCommands<'w, 's, '_> {
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let e = self.commands.spawn(bundle);
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self.push_children.children.push(e.id());
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e
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}
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/// Spawns an [`Entity`] with no components and inserts it into the parent entity's [`Children`].
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/// Also adds [`Parent`] component to the created entity.
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pub fn spawn_empty(&mut self) -> EntityCommands<'w, 's, '_> {
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let e = self.commands.spawn_empty();
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self.push_children.children.push(e.id());
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e
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}
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/// Returns the parent entity of this [`ChildBuilder`].
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pub fn parent_entity(&self) -> Entity {
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self.push_children.parent
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}
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/// Adds a command to be executed, like [`Commands::add`].
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pub fn add_command<C: Command + 'static>(&mut self, command: C) -> &mut Self {
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self.commands.add(command);
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self
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}
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}
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/// Trait for removing, adding and replacing children and parents of an entity.
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pub trait BuildChildren {
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/// Takes a closure which builds children for this entity using [`ChildBuilder`].
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fn with_children(&mut self, f: impl FnOnce(&mut ChildBuilder)) -> &mut Self;
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/// Pushes children to the back of the builder's children. For any entities that are
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/// already a child of this one, this method does nothing.
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///
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/// If the children were previously children of another parent, that parent's [`Children`] component
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/// will have those children removed from its list. Removing all children from a parent causes its
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/// [`Children`] component to be removed from the entity.
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///
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/// # Panics
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///
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/// Panics if any of the children are the same as the parent.
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fn push_children(&mut self, children: &[Entity]) -> &mut Self;
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/// Inserts children at the given index.
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///
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/// If the children were previously children of another parent, that parent's [`Children`] component
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/// will have those children removed from its list. Removing all children from a parent causes its
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/// [`Children`] component to be removed from the entity.
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///
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/// # Panics
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///
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/// Panics if any of the children are the same as the parent.
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fn insert_children(&mut self, index: usize, children: &[Entity]) -> &mut Self;
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/// Removes the given children
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///
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/// Removing all children from a parent causes its [`Children`] component to be removed from the entity.
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fn remove_children(&mut self, children: &[Entity]) -> &mut Self;
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/// Adds a single child.
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///
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/// If the children were previously children of another parent, that parent's [`Children`] component
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/// will have those children removed from its list. Removing all children from a parent causes its
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/// [`Children`] component to be removed from the entity.
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///
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/// # Panics
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///
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/// Panics if the child is the same as the parent.
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fn add_child(&mut self, child: Entity) -> &mut Self;
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/// Removes all children from this entity. The [`Children`] component will be removed if it exists, otherwise this does nothing.
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fn clear_children(&mut self) -> &mut Self;
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/// Removes all current children from this entity, replacing them with the specified list of entities.
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///
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/// The removed children will have their [`Parent`] component removed.
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///
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/// # Panics
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///
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/// Panics if any of the children are the same as the parent.
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fn replace_children(&mut self, children: &[Entity]) -> &mut Self;
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/// Sets the parent of this entity.
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///
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/// If this entity already had a parent, the parent's [`Children`] component will have this
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/// child removed from its list. Removing all children from a parent causes its [`Children`]
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/// component to be removed from the entity.
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///
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/// # Panics
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///
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/// Panics if the parent is the same as the child.
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fn set_parent(&mut self, parent: Entity) -> &mut Self;
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/// Removes the [`Parent`] of this entity.
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///
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/// Also removes this entity from its parent's [`Children`] component. Removing all children from a parent causes
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/// its [`Children`] component to be removed from the entity.
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fn remove_parent(&mut self) -> &mut Self;
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}
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impl<'w, 's, 'a> BuildChildren for EntityCommands<'w, 's, 'a> {
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fn with_children(&mut self, spawn_children: impl FnOnce(&mut ChildBuilder)) -> &mut Self {
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let parent = self.id();
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let mut builder = ChildBuilder {
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commands: self.commands(),
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push_children: PushChildren {
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children: SmallVec::default(),
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parent,
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},
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};
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spawn_children(&mut builder);
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let children = builder.push_children;
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if children.children.contains(&parent) {
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panic!("Entity cannot be a child of itself.");
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}
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self.commands().add(children);
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self
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}
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fn push_children(&mut self, children: &[Entity]) -> &mut Self {
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let parent = self.id();
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if children.contains(&parent) {
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panic!("Cannot push entity as a child of itself.");
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}
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self.commands().add(PushChildren {
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children: SmallVec::from(children),
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parent,
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});
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self
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}
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fn insert_children(&mut self, index: usize, children: &[Entity]) -> &mut Self {
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let parent = self.id();
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if children.contains(&parent) {
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panic!("Cannot insert entity as a child of itself.");
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}
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self.commands().add(InsertChildren {
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children: SmallVec::from(children),
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index,
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parent,
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});
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self
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}
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fn remove_children(&mut self, children: &[Entity]) -> &mut Self {
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let parent = self.id();
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self.commands().add(RemoveChildren {
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children: SmallVec::from(children),
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parent,
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});
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self
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}
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fn add_child(&mut self, child: Entity) -> &mut Self {
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let parent = self.id();
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if child == parent {
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panic!("Cannot add entity as a child of itself.");
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}
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self.commands().add(AddChild { child, parent });
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self
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}
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fn clear_children(&mut self) -> &mut Self {
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let parent = self.id();
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self.commands().add(ClearChildren { parent });
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self
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}
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fn replace_children(&mut self, children: &[Entity]) -> &mut Self {
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let parent = self.id();
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if children.contains(&parent) {
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panic!("Cannot replace entity as a child of itself.");
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}
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self.commands().add(ReplaceChildren {
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children: SmallVec::from(children),
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parent,
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});
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self
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}
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fn set_parent(&mut self, parent: Entity) -> &mut Self {
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let child = self.id();
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if child == parent {
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panic!("Cannot set parent to itself");
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}
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self.commands().add(AddChild { child, parent });
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self
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}
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fn remove_parent(&mut self) -> &mut Self {
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let child = self.id();
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self.commands().add(RemoveParent { child });
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self
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}
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}
|
|
|
|
/// Struct for adding children to an entity directly through the [`World`] for use in exclusive systems.
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#[derive(Debug)]
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pub struct WorldChildBuilder<'w> {
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world: &'w mut World,
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parent: Entity,
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}
|
|
|
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impl<'w> WorldChildBuilder<'w> {
|
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/// Spawns an entity with the given bundle and inserts it into the parent entity's [`Children`].
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/// Also adds [`Parent`] component to the created entity.
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|
pub fn spawn(&mut self, bundle: impl Bundle + Send + Sync + 'static) -> EntityWorldMut<'_> {
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let entity = self.world.spawn((bundle, Parent(self.parent))).id();
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push_child_unchecked(self.world, self.parent, entity);
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push_events(
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self.world,
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|
[HierarchyEvent::ChildAdded {
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child: entity,
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|
parent: self.parent,
|
|
}],
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);
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self.world.entity_mut(entity)
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|
}
|
|
|
|
/// Spawns an [`Entity`] with no components and inserts it into the parent entity's [`Children`].
|
|
/// Also adds [`Parent`] component to the created entity.
|
|
pub fn spawn_empty(&mut self) -> EntityWorldMut<'_> {
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let entity = self.world.spawn(Parent(self.parent)).id();
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push_child_unchecked(self.world, self.parent, entity);
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push_events(
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self.world,
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[HierarchyEvent::ChildAdded {
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child: entity,
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parent: self.parent,
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|
}],
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);
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self.world.entity_mut(entity)
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}
|
|
|
|
/// Returns the parent entity of this [`WorldChildBuilder`].
|
|
pub fn parent_entity(&self) -> Entity {
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self.parent
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}
|
|
}
|
|
|
|
/// Trait that defines adding, changing and children and parents of an entity directly through the [`World`].
|
|
pub trait BuildWorldChildren {
|
|
/// Takes a closure which builds children for this entity using [`WorldChildBuilder`].
|
|
fn with_children(&mut self, spawn_children: impl FnOnce(&mut WorldChildBuilder)) -> &mut Self;
|
|
|
|
/// Adds a single child.
|
|
///
|
|
/// If the children were previously children of another parent, that parent's [`Children`] component
|
|
/// will have those children removed from its list. Removing all children from a parent causes its
|
|
/// [`Children`] component to be removed from the entity.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if the child is the same as the parent.
|
|
fn add_child(&mut self, child: Entity) -> &mut Self;
|
|
|
|
/// Pushes children to the back of the builder's children. For any entities that are
|
|
/// already a child of this one, this method does nothing.
|
|
///
|
|
/// If the children were previously children of another parent, that parent's [`Children`] component
|
|
/// will have those children removed from its list. Removing all children from a parent causes its
|
|
/// [`Children`] component to be removed from the entity.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if any of the children are the same as the parent.
|
|
fn push_children(&mut self, children: &[Entity]) -> &mut Self;
|
|
/// Inserts children at the given index.
|
|
///
|
|
/// If the children were previously children of another parent, that parent's [`Children`] component
|
|
/// will have those children removed from its list. Removing all children from a parent causes its
|
|
/// [`Children`] component to be removed from the entity.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if any of the children are the same as the parent.
|
|
fn insert_children(&mut self, index: usize, children: &[Entity]) -> &mut Self;
|
|
/// Removes the given children
|
|
///
|
|
/// Removing all children from a parent causes its [`Children`] component to be removed from the entity.
|
|
fn remove_children(&mut self, children: &[Entity]) -> &mut Self;
|
|
|
|
/// Sets the parent of this entity.
|
|
///
|
|
/// If this entity already had a parent, the parent's [`Children`] component will have this
|
|
/// child removed from its list. Removing all children from a parent causes its [`Children`]
|
|
/// component to be removed from the entity.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if the parent is the same as the child.
|
|
fn set_parent(&mut self, parent: Entity) -> &mut Self;
|
|
|
|
/// Removes the [`Parent`] of this entity.
|
|
///
|
|
/// Also removes this entity from its parent's [`Children`] component. Removing all children from a parent causes
|
|
/// its [`Children`] component to be removed from the entity.
|
|
fn remove_parent(&mut self) -> &mut Self;
|
|
}
|
|
|
|
impl<'w> BuildWorldChildren for EntityWorldMut<'w> {
|
|
fn with_children(&mut self, spawn_children: impl FnOnce(&mut WorldChildBuilder)) -> &mut Self {
|
|
let parent = self.id();
|
|
self.world_scope(|world| {
|
|
spawn_children(&mut WorldChildBuilder { world, parent });
|
|
});
|
|
self
|
|
}
|
|
|
|
fn add_child(&mut self, child: Entity) -> &mut Self {
|
|
let parent = self.id();
|
|
if child == parent {
|
|
panic!("Cannot add entity as a child of itself.");
|
|
}
|
|
self.world_scope(|world| {
|
|
update_old_parent(world, child, parent);
|
|
});
|
|
if let Some(mut children_component) = self.get_mut::<Children>() {
|
|
children_component.0.retain(|value| child != *value);
|
|
children_component.0.push(child);
|
|
} else {
|
|
self.insert(Children::from_entities(&[child]));
|
|
}
|
|
self
|
|
}
|
|
|
|
fn push_children(&mut self, children: &[Entity]) -> &mut Self {
|
|
let parent = self.id();
|
|
if children.contains(&parent) {
|
|
panic!("Cannot push entity as a child of itself.");
|
|
}
|
|
self.world_scope(|world| {
|
|
update_old_parents(world, parent, children);
|
|
});
|
|
if let Some(mut children_component) = self.get_mut::<Children>() {
|
|
children_component
|
|
.0
|
|
.retain(|value| !children.contains(value));
|
|
children_component.0.extend(children.iter().cloned());
|
|
} else {
|
|
self.insert(Children::from_entities(children));
|
|
}
|
|
self
|
|
}
|
|
|
|
fn insert_children(&mut self, index: usize, children: &[Entity]) -> &mut Self {
|
|
let parent = self.id();
|
|
if children.contains(&parent) {
|
|
panic!("Cannot insert entity as a child of itself.");
|
|
}
|
|
self.world_scope(|world| {
|
|
update_old_parents(world, parent, children);
|
|
});
|
|
if let Some(mut children_component) = self.get_mut::<Children>() {
|
|
children_component
|
|
.0
|
|
.retain(|value| !children.contains(value));
|
|
children_component.0.insert_from_slice(index, children);
|
|
} else {
|
|
self.insert(Children::from_entities(children));
|
|
}
|
|
self
|
|
}
|
|
|
|
fn remove_children(&mut self, children: &[Entity]) -> &mut Self {
|
|
let parent = self.id();
|
|
self.world_scope(|world| {
|
|
remove_children(parent, children, world);
|
|
});
|
|
self
|
|
}
|
|
|
|
fn set_parent(&mut self, parent: Entity) -> &mut Self {
|
|
let child = self.id();
|
|
self.world_scope(|world| {
|
|
world.entity_mut(parent).add_child(child);
|
|
});
|
|
self
|
|
}
|
|
|
|
fn remove_parent(&mut self) -> &mut Self {
|
|
let child = self.id();
|
|
if let Some(parent) = self.take::<Parent>().map(|p| p.get()) {
|
|
self.world_scope(|world| {
|
|
remove_from_children(world, parent, child);
|
|
push_events(world, [HierarchyEvent::ChildRemoved { child, parent }]);
|
|
});
|
|
}
|
|
self
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::{BuildChildren, BuildWorldChildren};
|
|
use crate::{
|
|
components::{Children, Parent},
|
|
HierarchyEvent::{self, ChildAdded, ChildMoved, ChildRemoved},
|
|
};
|
|
use smallvec::{smallvec, SmallVec};
|
|
|
|
use bevy_ecs::{
|
|
component::Component,
|
|
entity::Entity,
|
|
event::Events,
|
|
system::{CommandQueue, Commands},
|
|
world::World,
|
|
};
|
|
|
|
/// Assert the (non)existence and state of the child's [`Parent`] component.
|
|
fn assert_parent(world: &mut World, child: Entity, parent: Option<Entity>) {
|
|
assert_eq!(world.get::<Parent>(child).map(|p| p.get()), parent);
|
|
}
|
|
|
|
/// Assert the (non)existence and state of the parent's [`Children`] component.
|
|
fn assert_children(world: &mut World, parent: Entity, children: Option<&[Entity]>) {
|
|
assert_eq!(world.get::<Children>(parent).map(|c| &**c), children);
|
|
}
|
|
|
|
/// Used to omit a number of events that are not relevant to a particular test.
|
|
fn omit_events(world: &mut World, number: usize) {
|
|
let mut events_resource = world.resource_mut::<Events<HierarchyEvent>>();
|
|
let mut events: Vec<_> = events_resource.drain().collect();
|
|
events_resource.extend(events.drain(number..));
|
|
}
|
|
|
|
fn assert_events(world: &mut World, expected_events: &[HierarchyEvent]) {
|
|
let events: Vec<_> = world
|
|
.resource_mut::<Events<HierarchyEvent>>()
|
|
.drain()
|
|
.collect();
|
|
assert_eq!(events, expected_events);
|
|
}
|
|
|
|
#[test]
|
|
fn add_child() {
|
|
let world = &mut World::new();
|
|
world.insert_resource(Events::<HierarchyEvent>::default());
|
|
|
|
let [a, b, c, d] = std::array::from_fn(|_| world.spawn_empty().id());
|
|
|
|
world.entity_mut(a).add_child(b);
|
|
|
|
assert_parent(world, b, Some(a));
|
|
assert_children(world, a, Some(&[b]));
|
|
assert_events(
|
|
world,
|
|
&[ChildAdded {
|
|
child: b,
|
|
parent: a,
|
|
}],
|
|
);
|
|
|
|
world.entity_mut(a).add_child(c);
|
|
|
|
assert_children(world, a, Some(&[b, c]));
|
|
assert_parent(world, c, Some(a));
|
|
assert_events(
|
|
world,
|
|
&[ChildAdded {
|
|
child: c,
|
|
parent: a,
|
|
}],
|
|
);
|
|
// Children component should be removed when it's empty.
|
|
world.entity_mut(d).add_child(b).add_child(c);
|
|
assert_children(world, a, None);
|
|
}
|
|
|
|
#[test]
|
|
fn set_parent() {
|
|
let world = &mut World::new();
|
|
world.insert_resource(Events::<HierarchyEvent>::default());
|
|
|
|
let [a, b, c] = std::array::from_fn(|_| world.spawn_empty().id());
|
|
|
|
world.entity_mut(a).set_parent(b);
|
|
|
|
assert_parent(world, a, Some(b));
|
|
assert_children(world, b, Some(&[a]));
|
|
assert_events(
|
|
world,
|
|
&[ChildAdded {
|
|
child: a,
|
|
parent: b,
|
|
}],
|
|
);
|
|
|
|
world.entity_mut(a).set_parent(c);
|
|
|
|
assert_parent(world, a, Some(c));
|
|
assert_children(world, b, None);
|
|
assert_children(world, c, Some(&[a]));
|
|
assert_events(
|
|
world,
|
|
&[ChildMoved {
|
|
child: a,
|
|
previous_parent: b,
|
|
new_parent: c,
|
|
}],
|
|
);
|
|
}
|
|
|
|
// regression test for https://github.com/bevyengine/bevy/pull/8346
|
|
#[test]
|
|
fn set_parent_of_orphan() {
|
|
let world = &mut World::new();
|
|
|
|
let [a, b, c] = std::array::from_fn(|_| world.spawn_empty().id());
|
|
world.entity_mut(a).set_parent(b);
|
|
assert_parent(world, a, Some(b));
|
|
assert_children(world, b, Some(&[a]));
|
|
|
|
world.entity_mut(b).despawn();
|
|
world.entity_mut(a).set_parent(c);
|
|
|
|
assert_parent(world, a, Some(c));
|
|
assert_children(world, c, Some(&[a]));
|
|
}
|
|
|
|
#[test]
|
|
fn remove_parent() {
|
|
let world = &mut World::new();
|
|
world.insert_resource(Events::<HierarchyEvent>::default());
|
|
|
|
let [a, b, c] = std::array::from_fn(|_| world.spawn_empty().id());
|
|
|
|
world.entity_mut(a).push_children(&[b, c]);
|
|
world.entity_mut(b).remove_parent();
|
|
|
|
assert_parent(world, b, None);
|
|
assert_parent(world, c, Some(a));
|
|
assert_children(world, a, Some(&[c]));
|
|
omit_events(world, 2); // Omit ChildAdded events.
|
|
assert_events(
|
|
world,
|
|
&[ChildRemoved {
|
|
child: b,
|
|
parent: a,
|
|
}],
|
|
);
|
|
|
|
world.entity_mut(c).remove_parent();
|
|
assert_parent(world, c, None);
|
|
assert_children(world, a, None);
|
|
assert_events(
|
|
world,
|
|
&[ChildRemoved {
|
|
child: c,
|
|
parent: a,
|
|
}],
|
|
);
|
|
}
|
|
|
|
#[derive(Component)]
|
|
struct C(u32);
|
|
|
|
#[test]
|
|
fn build_children() {
|
|
let mut world = World::default();
|
|
let mut queue = CommandQueue::default();
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
|
|
let parent = commands.spawn(C(1)).id();
|
|
let mut children = Vec::new();
|
|
commands.entity(parent).with_children(|parent| {
|
|
children.extend([
|
|
parent.spawn(C(2)).id(),
|
|
parent.spawn(C(3)).id(),
|
|
parent.spawn(C(4)).id(),
|
|
]);
|
|
});
|
|
|
|
queue.apply(&mut world);
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.as_slice(),
|
|
children.as_slice(),
|
|
);
|
|
assert_eq!(*world.get::<Parent>(children[0]).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(children[1]).unwrap(), Parent(parent));
|
|
|
|
assert_eq!(*world.get::<Parent>(children[0]).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(children[1]).unwrap(), Parent(parent));
|
|
}
|
|
|
|
#[test]
|
|
fn push_and_insert_and_remove_children_commands() {
|
|
let mut world = World::default();
|
|
let entities = world
|
|
.spawn_batch(vec![C(1), C(2), C(3), C(4), C(5)])
|
|
.collect::<Vec<Entity>>();
|
|
|
|
let mut queue = CommandQueue::default();
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(entities[0]).push_children(&entities[1..3]);
|
|
}
|
|
queue.apply(&mut world);
|
|
|
|
let parent = entities[0];
|
|
let child1 = entities[1];
|
|
let child2 = entities[2];
|
|
let child3 = entities[3];
|
|
let child4 = entities[4];
|
|
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child1, child2];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert_eq!(*world.get::<Parent>(child1).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(child2).unwrap(), Parent(parent));
|
|
|
|
assert_eq!(*world.get::<Parent>(child1).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(child2).unwrap(), Parent(parent));
|
|
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent).insert_children(1, &entities[3..]);
|
|
}
|
|
queue.apply(&mut world);
|
|
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child1, child3, child4, child2];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert_eq!(*world.get::<Parent>(child3).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(child4).unwrap(), Parent(parent));
|
|
|
|
let remove_children = [child1, child4];
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent).remove_children(&remove_children);
|
|
}
|
|
queue.apply(&mut world);
|
|
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child3, child2];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert!(world.get::<Parent>(child1).is_none());
|
|
assert!(world.get::<Parent>(child4).is_none());
|
|
}
|
|
|
|
#[test]
|
|
fn push_and_clear_children_commands() {
|
|
let mut world = World::default();
|
|
let entities = world
|
|
.spawn_batch(vec![C(1), C(2), C(3), C(4), C(5)])
|
|
.collect::<Vec<Entity>>();
|
|
|
|
let mut queue = CommandQueue::default();
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(entities[0]).push_children(&entities[1..3]);
|
|
}
|
|
queue.apply(&mut world);
|
|
|
|
let parent = entities[0];
|
|
let child1 = entities[1];
|
|
let child2 = entities[2];
|
|
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child1, child2];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert_eq!(*world.get::<Parent>(child1).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(child2).unwrap(), Parent(parent));
|
|
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent).clear_children();
|
|
}
|
|
queue.apply(&mut world);
|
|
|
|
assert!(world.get::<Children>(parent).is_none());
|
|
|
|
assert!(world.get::<Parent>(child1).is_none());
|
|
assert!(world.get::<Parent>(child2).is_none());
|
|
}
|
|
|
|
#[test]
|
|
fn push_and_replace_children_commands() {
|
|
let mut world = World::default();
|
|
let entities = world
|
|
.spawn_batch(vec![C(1), C(2), C(3), C(4), C(5)])
|
|
.collect::<Vec<Entity>>();
|
|
|
|
let mut queue = CommandQueue::default();
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(entities[0]).push_children(&entities[1..3]);
|
|
}
|
|
queue.apply(&mut world);
|
|
|
|
let parent = entities[0];
|
|
let child1 = entities[1];
|
|
let child2 = entities[2];
|
|
let child4 = entities[4];
|
|
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child1, child2];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert_eq!(*world.get::<Parent>(child1).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(child2).unwrap(), Parent(parent));
|
|
|
|
let replace_children = [child1, child4];
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent).replace_children(&replace_children);
|
|
}
|
|
queue.apply(&mut world);
|
|
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child1, child4];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert_eq!(*world.get::<Parent>(child1).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(child4).unwrap(), Parent(parent));
|
|
assert!(world.get::<Parent>(child2).is_none());
|
|
}
|
|
|
|
#[test]
|
|
fn push_and_insert_and_remove_children_world() {
|
|
let mut world = World::default();
|
|
let entities = world
|
|
.spawn_batch(vec![C(1), C(2), C(3), C(4), C(5)])
|
|
.collect::<Vec<Entity>>();
|
|
|
|
world.entity_mut(entities[0]).push_children(&entities[1..3]);
|
|
|
|
let parent = entities[0];
|
|
let child1 = entities[1];
|
|
let child2 = entities[2];
|
|
let child3 = entities[3];
|
|
let child4 = entities[4];
|
|
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child1, child2];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert_eq!(*world.get::<Parent>(child1).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(child2).unwrap(), Parent(parent));
|
|
|
|
world.entity_mut(parent).insert_children(1, &entities[3..]);
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child1, child3, child4, child2];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert_eq!(*world.get::<Parent>(child3).unwrap(), Parent(parent));
|
|
assert_eq!(*world.get::<Parent>(child4).unwrap(), Parent(parent));
|
|
|
|
let remove_children = [child1, child4];
|
|
world.entity_mut(parent).remove_children(&remove_children);
|
|
let expected_children: SmallVec<[Entity; 8]> = smallvec![child3, child2];
|
|
assert_eq!(
|
|
world.get::<Children>(parent).unwrap().0.clone(),
|
|
expected_children
|
|
);
|
|
assert!(world.get::<Parent>(child1).is_none());
|
|
assert!(world.get::<Parent>(child4).is_none());
|
|
}
|
|
|
|
/// Tests what happens when all children are removed from a parent using world functions
|
|
#[test]
|
|
fn children_removed_when_empty_world() {
|
|
let mut world = World::default();
|
|
let entities = world
|
|
.spawn_batch(vec![C(1), C(2), C(3)])
|
|
.collect::<Vec<Entity>>();
|
|
|
|
let parent1 = entities[0];
|
|
let parent2 = entities[1];
|
|
let child = entities[2];
|
|
|
|
// push child into parent1
|
|
world.entity_mut(parent1).push_children(&[child]);
|
|
assert_eq!(
|
|
world.get::<Children>(parent1).unwrap().0.as_slice(),
|
|
&[child]
|
|
);
|
|
|
|
// move only child from parent1 with `push_children`
|
|
world.entity_mut(parent2).push_children(&[child]);
|
|
assert!(world.get::<Children>(parent1).is_none());
|
|
|
|
// move only child from parent2 with `insert_children`
|
|
world.entity_mut(parent1).insert_children(0, &[child]);
|
|
assert!(world.get::<Children>(parent2).is_none());
|
|
|
|
// remove only child from parent1 with `remove_children`
|
|
world.entity_mut(parent1).remove_children(&[child]);
|
|
assert!(world.get::<Children>(parent1).is_none());
|
|
}
|
|
|
|
/// Tests what happens when all children are removed form a parent using commands
|
|
#[test]
|
|
fn children_removed_when_empty_commands() {
|
|
let mut world = World::default();
|
|
let entities = world
|
|
.spawn_batch(vec![C(1), C(2), C(3)])
|
|
.collect::<Vec<Entity>>();
|
|
|
|
let parent1 = entities[0];
|
|
let parent2 = entities[1];
|
|
let child = entities[2];
|
|
|
|
let mut queue = CommandQueue::default();
|
|
|
|
// push child into parent1
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent1).push_children(&[child]);
|
|
queue.apply(&mut world);
|
|
}
|
|
assert_eq!(
|
|
world.get::<Children>(parent1).unwrap().0.as_slice(),
|
|
&[child]
|
|
);
|
|
|
|
// move only child from parent1 with `push_children`
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent2).push_children(&[child]);
|
|
queue.apply(&mut world);
|
|
}
|
|
assert!(world.get::<Children>(parent1).is_none());
|
|
|
|
// move only child from parent2 with `insert_children`
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent1).insert_children(0, &[child]);
|
|
queue.apply(&mut world);
|
|
}
|
|
assert!(world.get::<Children>(parent2).is_none());
|
|
|
|
// move only child from parent1 with `add_child`
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent2).add_child(child);
|
|
queue.apply(&mut world);
|
|
}
|
|
assert!(world.get::<Children>(parent1).is_none());
|
|
|
|
// remove only child from parent2 with `remove_children`
|
|
{
|
|
let mut commands = Commands::new(&mut queue, &world);
|
|
commands.entity(parent2).remove_children(&[child]);
|
|
queue.apply(&mut world);
|
|
}
|
|
assert!(world.get::<Children>(parent2).is_none());
|
|
}
|
|
|
|
#[test]
|
|
fn regression_push_children_same_archetype() {
|
|
let mut world = World::new();
|
|
let child = world.spawn_empty().id();
|
|
world.spawn_empty().push_children(&[child]);
|
|
}
|
|
|
|
#[test]
|
|
fn push_children_idempotent() {
|
|
let mut world = World::new();
|
|
let child = world.spawn_empty().id();
|
|
let parent = world
|
|
.spawn_empty()
|
|
.push_children(&[child])
|
|
.push_children(&[child])
|
|
.id();
|
|
|
|
let mut query = world.query::<&Children>();
|
|
let children = query.get(&world, parent).unwrap();
|
|
assert_eq!(**children, [child]);
|
|
}
|
|
}
|