fix: avoid auto unsubscribe (due to gc) in js env

crates/loro-wasm/Cargo.toml

@@ -21,6 +21,7 @@ rle = { path = "../rle", package = "loro-rle" }
 tracing-wasm = "0.2.1"
 tracing = { version = "0.1", features = ["release_max_level_warn"] }
 serde_json = "1"
+once_cell.workspace = true
 
 [features]
 default = []

crates/loro-wasm/src/lib.rs

@@ -28,7 +28,7 @@ use loro_internal::{
 };
 use rle::HasLength;
 use serde::{Deserialize, Serialize};
-use std::{cell::RefCell, cmp::Ordering, rc::Rc, sync::Arc};
+use std::{cell::RefCell, cmp::Ordering, mem::ManuallyDrop, rc::Rc, sync::Arc};
 use wasm_bindgen::{__rt::IntoJsResult, prelude::*, throw_val};
 use wasm_bindgen_derive::TryFromJsValue;
 
@@ -4240,9 +4240,23 @@ fn js_to_export_mode(js_mode: JsExportMode) -> JsResult<ExportMode<'static>> {
 }
 
 fn subscription_to_js_function_callback(sub: Subscription) -> JsValue {
- let mut sub = Some(sub);
+ use once_cell::sync::Lazy;
+ use std::collections::HashMap;
+ use std::sync::Mutex;
+
+ static SUBSCRIPTION_MAP: Lazy<Mutex<HashMap<usize, Subscription>>> =
+ Lazy::new(|| Mutex::new(HashMap::new()));
+ static NEXT_ID: Lazy<Mutex<usize>> = Lazy::new(|| Mutex::new(0));
+
+ let id = {
+ let mut id = NEXT_ID.lock().unwrap();
+ *id += 1;
+ *id
+ };
+
+ SUBSCRIPTION_MAP.lock().unwrap().insert(id, sub);
  let closure = Closure::wrap(Box::new(move || {
- if let Some(sub) = sub.take() {
+ if let Some(sub) = SUBSCRIPTION_MAP.lock().unwrap().remove(&id) {
  sub.unsubscribe();
  }
  }) as Box<dyn FnMut()>);