events: show throw stack trace for uncaught exception

Show the stack trace for the `eventemitter.emit('error')` call
in the case of an uncaught exception.

Previously, there would be no clue in Node’s output about where
the actual `throw` comes from.

PR-URL: https://github.com/nodejs/node/pull/19003
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/test/message/events_unhandled_error_common_trace.js b/test/message/events_unhandled_error_common_trace.js
new file mode 100644
index 0000000000..e6c168fc06
--- /dev/null
+++ b/test/message/events_unhandled_error_common_trace.js
@@ -0,0 +1,20 @@
+'use strict';
+require('../common');
+const EventEmitter = require('events');
+
+function foo() {
+  function bar() {
+    return new Error('foo:bar');
+  }
+
+  return bar();
+}
+
+const ee = new EventEmitter();
+const err = foo();
+
+function quux() {
+  ee.emit('error', err);
+}
+
+quux();