The removal queries can react pooled entity when removing entity inside system

[ukjhsa]

I found that the removal queries of the former order system would get the wrong.

According to the docs, if an application has a running order as: SystemA > SystemB > SystemC and SystemB removes an entity, just SystemC will be able to react to it and SystemA will not be able to read that data. But I found that the SystemA will be able to react the entity that is in pools.

The example

    class TestComponent extends Component {}
    
    class BeforeSystem extends System {
      execute() {
        this.queries.as.added.forEach(entity => {
          console.log(`In BeforeSystem: entity id ${entity.id} added`);
        });
    
        this.queries.as.removed.forEach(entity => {
          console.log(`In BeforeSystem: entity id ${entity.id} removed, its alive: ${entity.alive}, its removed comp: ${!!entity.getRemovedComponent(TestComponent)}`);
        })
    
        this.queries.as.results.forEach(entity => {
          console.log(`In BeforeSystem: entity id ${entity.id} present`);
        })
      }
    }
    
    BeforeSystem.queries = {
      as: {
        components: [TestComponent],
        listen: {
          added: true,
          removed: true,
        }
      },
    }
    
    class RemoveSystem extends System {
      count = 0;
      execute() {
        this.queries.as.added.forEach(entity => {
          console.log(`In RemoveSystem: entity id ${entity.id} added`);
        });
    
        this.queries.as.removed.forEach(entity => {
          console.log(`In RemoveSystem: entity id ${entity.id} removed, its alive: ${entity.alive}, its removed comp: ${!!entity.getRemovedComponent(TestComponent)}`);
        })
    
        this.queries.as.results.forEach(entity => {
          console.log(`In RemoveSystem: entity id ${entity.id} present`);
          
          if (this.count === 1) {
            entity.remove();
            console.log(`In RemoveSystem: entity id ${entity.id} to be removed`);
          }
        })
    
        this.count++;
      }
    }
    
    RemoveSystem.queries = {
      as: {
        components: [TestComponent],
        listen: {
          added: true,
          removed: true,
        }
      },
    }
    
    class AfterSystem extends System {
      execute() {
        this.queries.as.added.forEach(entity => {
          console.log(`In AfterSystem: entity id ${entity.id} added`);
        });
    
        this.queries.as.removed.forEach(entity => {
          console.log(`In AfterSystem: entity id ${entity.id} removed, its alive: ${entity.alive}, its removed comp: ${!!entity.getRemovedComponent(TestComponent)}`);
        })
    
        this.queries.as.results.forEach(entity => {
          console.log(`In AfterSystem: entity id ${entity.id} present`);
        })
      }
    }
    
    AfterSystem.queries = {
      as: {
        components: [TestComponent],
        listen: {
          added: true,
          removed: true,
        }
      },
    }
    
    const world = new World();
    world.registerComponent(TestComponent);
    
    world.registerSystem(BeforeSystem);
    world.registerSystem(RemoveSystem);
    world.registerSystem(AfterSystem);
    
    const entity = world.createEntity();
    entity.addComponent(TestComponent);
    
    console.log('=== First frame ==');
    world.execute();
    console.log('=== Second frame ===');
    world.execute();
    console.log('=== Third frame ===');
    world.execute();

The output is

    === First frame ==
    In BeforeSystem: entity id 0 added
    In BeforeSystem: entity id 0 present
    In RemoveSystem: entity id 0 added
    In RemoveSystem: entity id 0 present
    In AfterSystem: entity id 0 added
    In AfterSystem: entity id 0 present
    === Second frame ===
    In BeforeSystem: entity id 0 present
    In RemoveSystem: entity id 0 present
    In RemoveSystem: entity id 0 to be removed
    In AfterSystem: entity id 0 removed, its alive: false, its removed comp: true
    === Third frame ===
    In BeforeSystem: entity id 1 removed, its alive: false, its removed comp: false

You can see that the BeforeSystem can react the entity with id 1 on second frame, is it a normal behavior?