From 0cdc87778e9c871e8bbbb081f4dc52fb17248e58 Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Wed, 7 Feb 2018 02:23:40 +0100
Subject: [PATCH] assert: show proper differences

Right now it is possible to get an AssertionError from input that has
the customInspect function set to always return the same value.

That way the error message is actually misleading because the output
is going to look the same. This fixes it by deactivating the custom
inspect function.

PR-URL: https://github.com/nodejs/node/pull/18611
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
---
 lib/internal/errors.js       | 10 ++++++----
 test/parallel/test-assert.js |  6 +++++-
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/lib/internal/errors.js b/lib/internal/errors.js
index 6d3b0557803..fb4f5e84822 100644
--- a/lib/internal/errors.js
+++ b/lib/internal/errors.js
@@ -164,9 +164,9 @@ function createErrDiff(actual, expected, operator) {
   var skipped = false;
   const util = lazyUtil();
   const actualLines = util
-    .inspect(actual, { compact: false }).split('\n');
+    .inspect(actual, { compact: false, customInspect: false }).split('\n');
   const expectedLines = util
-    .inspect(expected, { compact: false }).split('\n');
+    .inspect(expected, { compact: false, customInspect: false }).split('\n');
   const msg = `Input A expected to ${operator} input B:\n` +
         `${green}+ expected${white} ${red}- actual${white}`;
   const skippedMsg = ' ... Lines skipped';
@@ -310,8 +310,10 @@ class AssertionError extends Error {
       } else if (errorDiff === 1) {
         // In case the objects are equal but the operator requires unequal, show
         // the first object and say A equals B
-        const res = util
-          .inspect(actual, { compact: false }).split('\n');
+        const res = util.inspect(
+          actual,
+          { compact: false, customInspect: false }
+        ).split('\n');
 
         if (res.length > 20) {
           res[19] = '...';
diff --git a/test/parallel/test-assert.js b/test/parallel/test-assert.js
index f3f0012f842..c120f47302a 100644
--- a/test/parallel/test-assert.js
+++ b/test/parallel/test-assert.js
@@ -574,7 +574,11 @@ common.expectsError(
     message: `${start}\n` +
     `${actExp}\n` +
     '\n' +
-    '  {}'
+    `${minus} {}\n` +
+    `${plus} {\n` +
+    `${plus}   loop: 'forever',\n` +
+    `${plus}   [Symbol(util.inspect.custom)]: [Function]\n` +
+    `${plus} }`
   });
 
   // notDeepEqual tests