fix: Stop reconnect timer when event source is closed. (#29)

Currently the reconnect timer would elapse, discover the event source
was closed, and then do nothing. This is fine, but leaving the timer
open means that it can keep user applications running when they are
trying to exit. Stopping the timer will ensure we don't have any
outstanding async tasks that could prevent node from shutting down.

---------

Co-authored-by: Yusinto Ngadiman <yusinto@gmail.com>

example/eventsource-polyfill.js

@@ -7322,6 +7322,8 @@ function EventSource (url, eventSourceInitDict) {
 
   var streamOriginUrl = new URL(url).origin
 
+  let reconnectTimer
+
   function makeRequestUrlAndOptions () {
     // Returns { url, options }; url is null/undefined if the URL properties are in options
     var actualUrl = url
@@ -7430,7 +7432,9 @@ function EventSource (url, eventSourceInitDict) {
     event.delayMillis = delay
     _emit(event)
 
-    setTimeout(function () {
+    clearTimeout(reconnectTimer)
+
+    reconnectTimer = setTimeout(function () {
       if (readyState !== EventSource.CONNECTING) return
       connect()
     }, delay)
@@ -7605,6 +7609,8 @@ function EventSource (url, eventSourceInitDict) {
   }
 
   this._close = function () {
+    clearTimeout(reconnectTimer)
+
     if (readyState === EventSource.CLOSED) return
     readyState = EventSource.CLOSED
 

lib/eventsource.js

@@ -85,6 +85,8 @@ function EventSource (url, eventSourceInitDict) {
 
   var streamOriginUrl = new URL(url).origin
 
+  let reconnectTimer
+
   function makeRequestUrlAndOptions () {
     // Returns { url, options }; url is null/undefined if the URL properties are in options
     var actualUrl = url
@@ -193,7 +195,9 @@ function EventSource (url, eventSourceInitDict) {
     event.delayMillis = delay
     _emit(event)
 
-    setTimeout(function () {
+    clearTimeout(reconnectTimer)
+
+    reconnectTimer = setTimeout(function () {
       if (readyState !== EventSource.CONNECTING) return
       connect()
     }, delay)
@@ -368,6 +372,8 @@ function EventSource (url, eventSourceInitDict) {
   }
 
   this._close = function () {
+    clearTimeout(reconnectTimer)
+
     if (readyState === EventSource.CLOSED) return
     readyState = EventSource.CLOSED