repl: do not crash on async op reject (#3527)

2 files changed, 13 insertions, 0 deletions

diff --git a/cli/lib.rs b/cli/lib.rs
index df4cbbdf0..b191d5e87 100644
--- a/cli/lib.rs
+++ b/cli/lib.rs
@@ -349,6 +349,11 @@ fn bundle_command(flags: DenoFlags) {
 
 fn run_repl(flags: DenoFlags) {
   let (mut worker, _state) = create_worker_and_state(flags);
+  // Make repl continue to function under uncaught async errors.
+  worker.set_error_handler(Box::new(|err| {
+    eprintln!("{}", err.to_string());
+    Ok(())
+  }));
   // Setup runtime.
   js_check(worker.execute("denoMain()"));
   let main_future = async move {
diff --git a/cli/worker.rs b/cli/worker.rs
index 814e7f440..e35458d39 100644
--- a/cli/worker.rs
+++ b/cli/worker.rs
@@ -96,6 +96,14 @@ impl Worker {
     }
   }
 
+  pub fn set_error_handler(
+    &mut self,
+    handler: Box<dyn FnMut(ErrBox) -> Result<(), ErrBox>>,
+  ) {
+    let mut i = self.isolate.lock().unwrap();
+    i.set_error_handler(handler);
+  }
+
   /// Same as execute2() but the filename defaults to "$CWD/__anonymous__".
   pub fn execute(&mut self, js_source: &str) -> Result<(), ErrBox> {
     let path = env::current_dir().unwrap().join("__anonymous__");