From f0b6e395ff57e61bcda10335fb1ad5e8a2753903 Mon Sep 17 00:00:00 2001
From: Rich Trott <rtrott@gmail.com>
Date: Fri, 24 Jun 2016 15:37:38 -0700
Subject: [PATCH] assert: remove unneeded arguments special handling

Remove special handling when asserting on a pair of arguments objects.
The code being removed will only run if both `expected` and `actual` are
arguments objects. Given that situation, the subsequent code for
handling everything else works just fine.

Tests added to confirm expected behavior.

This came about while trying to improve test coverage. The segment of
code removed had no test coverage. I was unable to write a test that
would both exercise the code and fail if the code was removed. Further
examination indicated that this was because the special handling was not
needed.
---
 lib/assert.js                |  6 ------
 test/parallel/test-assert.js | 16 +++++++++++++++-
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/lib/assert.js b/lib/assert.js
index 8955aa8761d7c2..ba316d38ff665f 100644
--- a/lib/assert.js
+++ b/lib/assert.js
@@ -28,7 +28,6 @@
 const compare = process.binding('buffer').compare;
 const util = require('util');
 const Buffer = require('buffer').Buffer;
-const pSlice = Array.prototype.slice;
 const pToString = (obj) => Object.prototype.toString.call(obj);
 
 // 1. The assert module provides functions that throw
@@ -223,11 +222,6 @@ function objEquiv(a, b, strict, actualVisitedObjects) {
   const bIsArgs = isArguments(b);
   if ((aIsArgs && !bIsArgs) || (!aIsArgs && bIsArgs))
     return false;
-  if (aIsArgs) {
-    a = pSlice.call(a);
-    b = pSlice.call(b);
-    return _deepEqual(a, b, strict);
-  }
   const ka = Object.keys(a);
   const kb = Object.keys(b);
   var key, i;
diff --git a/test/parallel/test-assert.js b/test/parallel/test-assert.js
index b2e2ea4debfbc5..34e7b643442138 100644
--- a/test/parallel/test-assert.js
+++ b/test/parallel/test-assert.js
@@ -59,7 +59,7 @@ assert.throws(makeBlock(a.strictEqual, null, undefined),
 assert.doesNotThrow(makeBlock(a.notStrictEqual, 2, '2'),
                     'notStrictEqual(2, \'2\')');
 
-// deepEquals joy!
+// deepEqual joy!
 // 7.2
 assert.doesNotThrow(makeBlock(a.deepEqual, new Date(2000, 3, 14),
                     new Date(2000, 3, 14)),
@@ -409,6 +409,20 @@ var args = (function() { return arguments; })();
 a.throws(makeBlock(a.deepEqual, [], args));
 a.throws(makeBlock(a.deepEqual, args, []));
 
+// more checking that arguments objects are handled correctly
+{
+  const returnArguments = function() { return arguments; };
+
+  const someArgs = returnArguments('a');
+  const sameArgs = returnArguments('a');
+  const diffArgs = returnArguments('b');
+
+  a.throws(makeBlock(a.deepEqual, someArgs, ['a']));
+  a.throws(makeBlock(a.deepEqual, ['a'], someArgs));
+  a.throws(makeBlock(a.deepEqual, someArgs, {'0': 'a'}));
+  a.throws(makeBlock(a.deepEqual, someArgs, diffArgs));
+  a.doesNotThrow(makeBlock(a.deepEqual, someArgs, sameArgs));
+}
 
 var circular = {y: 1};
 circular.x = circular;