Pumpkin-MC/Pumpkin · error

unexpected event

Error message

unexpected event

What it means

This panic fires inside `data_from_event` for EntityExhaustionEvent when the incoming `Event` is not `Event::EntityExhaustionEvent`. The function unwraps the generic `Event` enum into `EntityExhaustionEventData`, panicking on any other variant since the dispatcher contract guarantees a match. It fires when the event-routing invariant is violated.

Solutions

1. Route only `Event::EntityExhaustionEvent(data)` through this handler
2. Verify the event's `EventType` before unwrapping
3. Keep plugin-api and host versions synchronized
4. Replace the panic with a logged error or `Option` return for resilience

Example fix

// before
<EntityExhaustionEvent as Event>::data_from_event(Event::EntityRegainHealthEvent(d));
// after
<EntityExhaustionEvent as Event>::data_from_event(Event::EntityExhaustionEvent(d));

if !matches!(event, Event::EntityExhaustionEvent(_)) { return; }
<crate::events::entity::entity_exhaustion::EntityExhaustionEvent as Event>::data_from_event(event);

fn as_entity_exhaustion(event: &Event) -> Option<&EntityExhaustionEventData> {
    match event { Event::EntityExhaustionEvent(d) => Some(d), _ => None }
}

// guard before unwrapping:
if let Event::EntityExhaustionEvent(data) = event {
    // use data
} else {
    log::error!("misrouted event: expected EntityExhaustionEvent");
}

When it happens

Trigger: Passing a non-`EntityExhaustionEvent` variant into `data_from_event` — manual dispatch with the wrong variant, a dispatcher that pairs `EventType::EntityExhaustionEvent` with foreign data, or test code misusing the impl.

Common situations: Copy-paste dispatch in test harnesses; event buses that skip `EventType` verification; plugin-api/server version drift.

Understand the failure class

Background: "This is a bug, please report it": internal invariant violations, unreachable panics, and SNH errors explained — this error's family across 47 libraries.

Related errors

• unexpected event
• unexpected event
• unexpected event
• unexpected event
• unexpected event

AI-assisted analysis of Pumpkin-MC/Pumpkin@8d4639e25a (2026-09-09). Data as JSON: /api/errors/06284c4d94e32462. Report an issue: GitHub.

Appendix: source

Thrown at crates/pumpkin-plugin-api/src/events/entity/entity_exhaustion.rs:14

use crate::wit::pumpkin::plugin::event::{EntityExhaustionEventData, Event, EventType};

use super::super::FromIntoEvent;

/// Event triggered when an entity experiences hunger exhaustion.
pub struct EntityExhaustionEvent;
impl FromIntoEvent for EntityExhaustionEvent {
    const EVENT_TYPE: EventType = EventType::EntityExhaustionEvent;
    type Data = EntityExhaustionEventData;

    fn data_from_event(event: Event) -> Self::Data {
        match event {
            Event::EntityExhaustionEvent(data) => data,
            _ => panic!("unexpected event"),
        }
    }

    fn data_into_event(data: Self::Data) -> Event {
        Event::EntityExhaustionEvent(data)
    }
}

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