timers: truncate decimal values

Reverts some timers behavior back to as it was before
2930bd1317d15d12738a4896c0a6c05700411b47

That commit introduced an unintended change which allowed non-integer
timeouts to actually exist since the value is no longer converted to an
integer via a TimeWrap handle directly.

Even with the fix in
e9de43549843da9f4f081cce917945878967df7
non-integer timeouts are still indeterministic, because libuv does not
support them.

This fixes the issue by emulating the old behavior:
truncate the `_idleTimeout` before using it.

See comments in
https://github.com/nodejs/node/pull/24214
for more background on this.

PR-URL: https://github.com/nodejs/node/pull/24819
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/test/parallel/test-timers-non-integer-delay.js b/test/parallel/test-timers-non-integer-delay.js
index 017ef28d0f..a57922e3c7 100644
--- a/test/parallel/test-timers-non-integer-delay.js
+++ b/test/parallel/test-timers-non-integer-delay.js
@@ -21,6 +21,7 @@
 
 'use strict';
 const common = require('../common');
+const assert = require('assert');
 
 /*
  * This test makes sure that non-integer timer delays do not make the process
@@ -47,3 +48,37 @@ const interval = setInterval(common.mustCall(() => {
     process.exit(0);
   }
 }, N), TIMEOUT_DELAY);
+
+// Test non-integer delay ordering
+{
+  const ordering = [];
+
+  setTimeout(common.mustCall(() => {
+    ordering.push(1);
+  }), 1);
+
+  setTimeout(common.mustCall(() => {
+    ordering.push(2);
+  }), 1.8);
+
+  setTimeout(common.mustCall(() => {
+    ordering.push(3);
+  }), 1.1);
+
+  setTimeout(common.mustCall(() => {
+    ordering.push(4);
+  }), 1);
+
+  setTimeout(common.mustCall(() => {
+    const expected = [1, 2, 3, 4];
+
+    assert.deepStrictEqual(
+      ordering,
+      expected,
+      `Non-integer delay ordering should be ${expected}, but got ${ordering}`
+    );
+
+    // 2 should always be last of these delays due to ordering guarentees by
+    // the implementation.
+  }), 2);
+}