fix: unhandledrejection handling for sync throw in top level (#15279)

Fixes an edge in "unhandledrejection" event that prevent synchronous
errors being surfaced when throw from a top-level scope.

1 files changed, 6 insertions, 0 deletions

diff --git a/cli/tests/testdata/unhandled_rejection_sync_error.ts b/cli/tests/testdata/unhandled_rejection_sync_error.ts
new file mode 100644
index 000000000..0dabb1cb7
--- /dev/null
+++ b/cli/tests/testdata/unhandled_rejection_sync_error.ts
@@ -0,0 +1,6 @@
+globalThis.addEventListener("unhandledrejection", (e) => {
+  console.log("unhandled rejection at:", e.promise, "reason:", e.reason);
+  e.preventDefault();
+});
+
+throw new Error("boom!");