Pumpkin-MC/Pumpkin · error

failed to add player resource

Error message

failed to add player resource

What it means

to_wasm_event for EntityTameEvent calls PluginHostState::add_player to register the taming owner (an Arc<Player>) in the WASM resource table and .expect()s success; if the resource cannot be inserted, the host panics with "failed to add player resource". add_player can fail when the linear-component resource table cannot allocate a new handle (e.g. table limits) or the store/state is in a bad state, so the tame event can never be serialized for the guest.

Solutions

1. Check whether add_player failures correlate with resource-table exhaustion; ensure consume_player/cleanup_event runs for every added player resource
2. Update wasmtime/pumpkin to a version that grows the resource table or returns errors gracefully
3. Ensure the plugin's store/instance is alive and healthy when entity events fire
4. Replace the .expect with logged error + event skip so one bad conversion doesn't kill the server thread

Example fix

// before
let owner = state
    .add_player(self.owner.clone())
    .expect("failed to add player resource");
// after
let owner = match state.add_player(self.owner.clone()) {
    Ok(o) => o,
    Err(e) => {
        log::error!("skipping EntityTameEvent: add_player failed: {e}");
        return Event::NoEvent; // or propagate an error
    }
};

// before firing the event, ensure the state/store is usable
if state.resource_table_is_full() { log::warn!("player resource table full; skipping EntityTameEvent"); return; }

fn can_add_player(state: &PluginHostState, p: &Arc<Player>) -> bool { !state.is_torn_down() && state.player_table_has_capacity() }

match state.add_player(owner.clone()) {
    Ok(h) => build_event(h),
    Err(e) => log::error!("EntityTameEvent dropped: {e}"), // don't .expect in hot event paths
}

When it happens

Trigger: An EntityTameEvent fires and state.add_player(self.owner) returns Err — resource-table allocation failure in the wasmtime instance, calling with a PluginHostState whose store is torn down, or a resource handle leak exhausting the table over many events.

Common situations: Long-running servers where player/bossbar resources are added without cleanup, eventually hitting wasmtime resource-table limits; plugins crashing mid-event leaving the host state inconsistent.

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

• failed to add player resource
• failed to add world resource
• failed to add world resource
• failed to add player resource
• unexpected event type

AI-assisted analysis of Pumpkin-MC/Pumpkin@8d4639e25a (2026-09-09). Data as JSON: /api/errors/4ba6b5b89fbedfb8. Report an issue: GitHub.

Appendix: source

Thrown at crates/pumpkin/src/plugin/loader/wasm/wasm_host/wit/v0_1/events/entity.rs:524

    fn from_wasm_event(event: Event, _state: &mut PluginHostState) -> Self {
        match event {
            Event::EntityShootBowEvent(data) => Self {
                entity_id: data.entity_id,
                weapon_name: data.weapon_name,
                force: data.force,
                cancelled: data.cancelled,
            },
            _ => panic!("unexpected event type"),
        }
    }
}

impl ToFromWasmEvent for crate::plugin::api::events::entity::entity_tame::EntityTameEvent {
    fn to_wasm_event(&self, state: &mut PluginHostState) -> Event {
        let owner = state
            .add_player(self.owner.clone())
            .expect("failed to add player resource");
        Event::EntityTameEvent(EntityTameEventData {
            entity_id: self.entity_id,
            owner,
            cancelled: self.cancelled,
        })
    }

    fn from_wasm_event(event: Event, state: &mut PluginHostState) -> Self {
        match event {
            Event::EntityTameEvent(data) => Self {
                entity_id: data.entity_id,
                owner: consume_player(state, &data.owner),
                cancelled: data.cancelled,
            },
            _ => panic!("unexpected event type"),
        }
    }
}

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