test: add util.isDeepStrictEqual edge case tests

Test for deep strict equality when prototype and toStringTag
have been modified in surprising ways.

PR-URL: https://github.com/nodejs/node/pull/25932
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/test/parallel/test-util-isDeepStrictEqual.js b/test/parallel/test-util-isDeepStrictEqual.js
index 0eb75e46eb..08a30a28db 100644
--- a/test/parallel/test-util-isDeepStrictEqual.js
+++ b/test/parallel/test-util-isDeepStrictEqual.js
@@ -449,6 +449,31 @@ assert.strictEqual(
   notUtilIsDeepStrict(boxedSymbol, {});
   utilIsDeepStrict(Object(BigInt(1)), Object(BigInt(1)));
   notUtilIsDeepStrict(Object(BigInt(1)), Object(BigInt(2)));
+
+  const booleanish = new Boolean(true);
+  Object.defineProperty(booleanish, Symbol.toStringTag, { value: 'String' });
+  Object.setPrototypeOf(booleanish, String.prototype);
+  notUtilIsDeepStrict(booleanish, new String('true'));
+
+  const numberish = new Number(42);
+  Object.defineProperty(numberish, Symbol.toStringTag, { value: 'String' });
+  Object.setPrototypeOf(numberish, String.prototype);
+  notUtilIsDeepStrict(numberish, new String('42'));
+
+  const stringish = new String('0');
+  Object.defineProperty(stringish, Symbol.toStringTag, { value: 'Number' });
+  Object.setPrototypeOf(stringish, Number.prototype);
+  notUtilIsDeepStrict(stringish, new Number(0));
+
+  const bigintish = new Object(BigInt(42));
+  Object.defineProperty(bigintish, Symbol.toStringTag, { value: 'String' });
+  Object.setPrototypeOf(bigintish, String.prototype);
+  notUtilIsDeepStrict(bigintish, new String('42'));
+
+  const symbolish = new Object(Symbol('fhqwhgads'));
+  Object.defineProperty(symbolish, Symbol.toStringTag, { value: 'String' });
+  Object.setPrototypeOf(symbolish, String.prototype);
+  notUtilIsDeepStrict(symbolish, new String('fhqwhgads'));
 }
 
 // Minus zero