fixup! lib: replace validator and error

Reverted the changes to the `validateFunction()` validator, added
`code` after `error`, removed the link re-directing to
`ERR_INAVLID_ARG_TYPE` error code, and reverted the changes to the
`ERR_INVALID_ARG_TYPE` error code.

doc/api/deprecations.md

@@ -3067,11 +3067,9 @@ changes:
 
 Type: End-of-Life
 
-This error was removed due to adding more confusion to
+This error code was removed due to adding more confusion to
 the errors used for value type validation.
 
-Use [`ERR_INVALID_ARG_TYPE`][] instead.
-
 [Legacy URL API]: url.md#legacy-url-api
 [NIST SP 800-38D]: https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf
 [RFC 6066]: https://tools.ietf.org/html/rfc6066#section-3
@@ -3086,7 +3084,6 @@ Use [`ERR_INVALID_ARG_TYPE`][] instead.
 [`Buffer.isBuffer()`]: buffer.md#static-method-bufferisbufferobj
 [`Cipher`]: crypto.md#class-cipher
 [`Decipher`]: crypto.md#class-decipher
-[`ERR_INVALID_ARG_TYPE`]: errors.md#err_invalid_arg_type
 [`REPLServer.clearBufferedCommand()`]: repl.md#replserverclearbufferedcommand
 [`ReadStream.open()`]: fs.md#class-fsreadstream
 [`Server.getConnections()`]: net.md#servergetconnectionscallback

lib/internal/errors.js

@@ -1208,10 +1208,7 @@ E('ERR_INVALID_ARG_TYPE',
     if (actual == null) {
       msg += `. Received ${actual}`;
     } else if (typeof actual === 'function' && actual.name) {
-      const inspected = lazyInternalUtilInspect()
-        .inspect(actual);
-      msg += `. Received ${inspected.startsWith('[class') ?
-        'class' : 'function'} ${actual.name}`;
+      msg += `. Received function ${actual.name}`;
     } else if (typeof actual === 'object') {
       if (actual.constructor && actual.constructor.name) {
         msg += `. Received an instance of ${actual.constructor.name}`;

lib/internal/perf/timerify.js

@@ -56,7 +56,7 @@ function processComplete(name, start, args, histogram) {
 }
 
 function timerify(fn, options = {}) {
-  validateFunction(fn, 'fn', true);
+  validateFunction(fn, 'fn');
 
   validateObject(options, 'options');
   const {

lib/internal/validators.js

@@ -32,8 +32,6 @@ const {
 } = require('internal/util/types');
 const { signals } = internalBinding('constants').os;
 
-let inspect;
-
 function isInt32(value) {
   return value === (value | 0);
 }
@@ -229,17 +227,9 @@ const validateAbortSignal = hideStackFrames((signal, name) => {
   }
 });
 
-const validateFunction = hideStackFrames((value, name, allowClass = false) => {
-  if (typeof value === 'function') {
-    if (allowClass) return;
-
-    if (inspect === undefined)
-      ({ inspect } = require('util'));
-
-    if (!inspect(value).startsWith('[class')) return;
-  }
-
-  throw new ERR_INVALID_ARG_TYPE(name, 'Function', value);
+const validateFunction = hideStackFrames((value, name) => {
+  if (typeof value !== 'function')
+    throw new ERR_INVALID_ARG_TYPE(name, 'Function', value);
 });
 
 const validatePlainFunction = hideStackFrames((value, name) => {