assert,util: improve deep equal comparison performance

This is mainly a performance improvement for a lot of simple cases.
Diverging elements are detected earlier and equal entries are
partially also detected faster.

A small correctness patch is also included where recursions now
stop as soon as either side has a circular structure. Before, both
sides had to have a circular structure at the specific comparison
which could have caused more checks that likely fail at a later
point.

Signed-off-by: Ruben Bridgewater <ruben@bridgewater.de>
PR-URL: #46593
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

benchmark/assert/deepequal-object.js

@@ -12,7 +12,8 @@ const bench = common.createBenchmark(main, {
   combinationFilter: (p) => {
     return p.size === 1e4 && p.n === 25 ||
            p.size === 1e3 && p.n === 2e2 ||
-           p.size === 1e2 && p.n === 2e3;
+           p.size === 1e2 && p.n === 2e3 ||
+           p.size === 1;
   },
 });
 

doc/api/assert.md

@@ -546,6 +546,10 @@ An alias of [`assert.ok()`][].
 <!-- YAML
 added: v0.1.21
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/46593
+    description: Recursion now stops when either side encounters a circular
+                 reference.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41020
     description: Regular expressions lastIndex property is now compared as well.
@@ -617,7 +621,7 @@ are also recursively evaluated by the following rules.
 * [Object wrappers][] are compared both as objects and unwrapped values.
 * `Object` properties are compared unordered.
 * [`Map`][] keys and [`Set`][] items are compared unordered.
-* Recursion stops when both sides differ or both sides encounter a circular
+* Recursion stops when both sides differ or either side encounters a circular
   reference.
 * Implementation does not test the [`[[Prototype]]`][prototype-spec] of
   objects.
@@ -727,6 +731,10 @@ parameter is an instance of an [`Error`][] then it will be thrown instead of the
 <!-- YAML
 added: v1.2.0
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/46593
+    description: Recursion now stops when either side encounters a circular
+                 reference.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41020
     description: Regular expressions lastIndex property is now compared as well.
@@ -780,7 +788,7 @@ are recursively evaluated also by the following rules.
 * [Object wrappers][] are compared both as objects and unwrapped values.
 * `Object` properties are compared unordered.
 * [`Map`][] keys and [`Set`][] items are compared unordered.
-* Recursion stops when both sides differ or both sides encounter a circular
+* Recursion stops when both sides differ or either side encounters a circular
   reference.
 * [`WeakMap`][] and [`WeakSet`][] comparison does not rely on their values. See
   below for further details.