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. Backport-PR-URL: #19230 PR-URL: #18611 Reviewed-By: Joyee Cheung <[email protected]> Reviewed-By: Matteo Collina <[email protected]> Reviewed-By: Anna Henningsen <[email protected]>

Author: BridgeAR

lib/internal/errors.js

@@ -90,9 +90,9 @@ function createErrDiff(actual, expected, operator){
 varskipped=false;
 constutil=lazyUtil();
 constactualLines=util
-.inspect(actual,{compact: false}).split('\n');
+.inspect(actual,{compact: false,customInspect: false}).split('\n');
 constexpectedLines=util
-.inspect(expected,{compact: false}).split('\n');
+.inspect(expected,{compact: false,customInspect: false}).split('\n');
 constmsg=`Input A expected to ${operator} input B:\n`+
 `${green}+ expected${white}${red}- actual${white}`;
 constskippedMsg=' ... Lines skipped';
@@ -235,8 +235,10 @@ class AssertionError extends Error{
 }elseif(errorDiff===1){
 // In case the objects are equal but the operator requires unequal, show
 // the first object and say A equals B
-constres=util
-.inspect(actual,{compact: false}).split('\n');
+constres=util.inspect(
+actual,
+{compact: false,customInspect: false}
+).split('\n');
 
 if(res.length>20){
 res[19]='...';

test/parallel/test-assert.js

@@ -899,7 +899,11 @@ 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