[oden-js] Track rejected promises, panic on unhandled rejections

oden-js/src/promise.rs

@@ -1,4 +1,4 @@
-use crate::{ContextRef, ValueResult};
+use crate::{ContextRef, ValueRef, ValueResult};
 use std::sync::atomic::{AtomicU64, Ordering};
 use std::sync::mpsc::Sender;
 
@@ -72,3 +72,53 @@ impl Drop for Promise {
         assert!(self.complete);
     }
 }
+
+pub trait RejectedPromiseTracker {
+    fn on_rejected_promise(
+        &self,
+        ctx: &ContextRef,
+        promise: &ValueRef,
+        reason: &ValueRef,
+        is_handled: bool,
+    );
+}
+
+impl<T> RejectedPromiseTracker for T
+where
+    T: Fn(&ContextRef, &ValueRef, &ValueRef, bool) -> (),
+{
+    fn on_rejected_promise(
+        &self,
+        ctx: &ContextRef,
+        promise: &ValueRef,
+        reason: &ValueRef,
+        is_handled: bool,
+    ) {
+        self(ctx, promise, reason, is_handled);
+    }
+}
+
+pub struct DefaultRejectedPromiseTracker {}
+
+impl DefaultRejectedPromiseTracker {
+    pub fn new() -> Self {
+        DefaultRejectedPromiseTracker {}
+    }
+}
+
+impl RejectedPromiseTracker for DefaultRejectedPromiseTracker {
+    fn on_rejected_promise(
+        &self,
+        ctx: &ContextRef,
+        _promise: &ValueRef,
+        reason: &ValueRef,
+        is_handled: bool,
+    ) {
+        if !is_handled {
+            let reason_str = reason.to_string(ctx).expect(
+                "Unhandled rejected promise: reason unknown: unable to convert reason to string",
+            );
+            panic!("Unhandled rejected promise: {reason_str}");
+        }
+    }
+}