timers: add hasRef method to Timeout & Immediate

Provide a way to check whether the current timer or immediate is refed.

PR-URL: https://github.com/nodejs/node/pull/20898
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/lib/timers.js b/lib/timers.js
index 3d200344a4..5ae0e6a5ad 100644
--- a/lib/timers.js
+++ b/lib/timers.js
@@ -547,6 +547,10 @@ Timeout.prototype.ref = function() {
   return this;
 };
 
+Timeout.prototype.hasRef = function() {
+  return !!this[kRefed];
+};
+
 Timeout.prototype.close = function() {
   clearTimeout(this);
   return this;
@@ -622,7 +626,7 @@ function processImmediate() {
     count++;
     if (immediate[kRefed])
       refCount++;
-    immediate[kRefed] = undefined;
+    immediate[kRefed] = null;
 
     tryOnImmediate(immediate, tail, count, refCount);
 
@@ -713,6 +717,10 @@ const Immediate = class Immediate {
     }
     return this;
   }
+
+  hasRef() {
+    return !!this[kRefed];
+  }
 };
 
 function setImmediate(callback, arg1, arg2, arg3) {
@@ -761,7 +769,7 @@ exports.clearImmediate = function clearImmediate(immediate) {
 
   if (immediate[kRefed] && --immediateInfo[kRefCount] === 0)
     toggleImmediateRef(false);
-  immediate[kRefed] = undefined;
+  immediate[kRefed] = null;
 
   if (destroyHooksExist()) {
     emitDestroy(immediate[async_id_symbol]);