timers: fix regression with clearImmediate()

This commit fixes a regression introduced in 0ed8839 that caused additional queued immediate callbacks to be ignored if `clearImmediate(immediate)` was called within the callback for `immediate`. PR-URL: #9086 Fixes: #9084 Reviewed-By: Rich Trott <[email protected]> Reviewed-By: Jeremiah Senkpiel <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Evan Lucas <[email protected]>
nodejs · Oct 14, 2016 · 1d8f068 · 1d8f068
1 parent 8b90814
commit 1d8f068
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diff --git a/lib/timers.js b/lib/timers.js
@@ -575,12 +575,21 @@ function processImmediate() {
       domain.enter();
 
     immediate._callback = immediate._onImmediate;
+
+    // Save next in case `clearImmediate(immediate)` is called from callback
+    var next = immediate._idleNext;
+
     tryOnImmediate(immediate, tail);
 
     if (domain)
       domain.exit();
 
-    immediate = immediate._idleNext;
+    // If `clearImmediate(immediate)` wasn't called from the callback, use the
+    // `immediate`'s next item
+    if (immediate._idleNext)
+      immediate = immediate._idleNext;
+    else
+      immediate = next;
   }
 
   // Only round-trip to C++ land if we have to. Calling clearImmediate() on an

diff --git a/test/parallel/test-timers-clearImmediate.js b/test/parallel/test-timers-clearImmediate.js
@@ -0,0 +1,18 @@
+'use strict';
+require('../common');
+const assert = require('assert');
+
+const N = 3;
+var count = 0;
+function next() {
+  const immediate = setImmediate(function() {
+    clearImmediate(immediate);
+    ++count;
+  });
+}
+for (var i = 0; i < N; ++i)
+  next();
+
+process.on('exit', () => {
+  assert.strictEqual(count, N, `Expected ${N} immediate callback executions`);
+});