util: move util.isFunction to eol

PR-URL: #52744
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz.nizipli@sentry.io>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Ulises Gascón <ulisesgascongonzalez@gmail.com>
Reviewed-By: Paolo Insogna <paolo@cowtech.it>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: marco-ippolito

Diff for: doc/api/deprecations.md

@@ -1105,6 +1105,9 @@ instead.
 
 <!-- YAML
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/52744
+    description: End-of-Life deprecation.
   - version: v22.0.0
     pr-url: https://github.com/nodejs/node/pull/50488
     description: Runtime deprecation.
@@ -1120,9 +1123,9 @@ changes:
     description: Documentation-only deprecation.
 -->
 
-Type: Runtime
+Type: End-of-Life
 
-The [`util.isFunction()`][] API is deprecated. Please use
+The `util.isFunction()` API has been removed. Please use
 `typeof arg === 'function'` instead.
 
 ### DEP0050: `util.isNull()`

Diff for: doc/api/util.md

@@ -2950,35 +2950,6 @@ util.isArray({});
 // Returns: false
 ```
 
-### `util.isFunction(object)`
-
-<!-- YAML
-added: v0.11.5
-deprecated: v4.0.0
--->
-
-> Stability: 0 - Deprecated: Use `typeof value === 'function'` instead.
-
-* `object` {any}
-* Returns: {boolean}
-
-Returns `true` if the given `object` is a `Function`. Otherwise, returns
-`false`.
-
-```js
-const util = require('node:util');
-
-function Foo() {}
-const Bar = () => {};
-
-util.isFunction({});
-// Returns: false
-util.isFunction(Foo);
-// Returns: true
-util.isFunction(Bar);
-// Returns: true
-```
-
 ### `util.isPrimitive(object)`
 
 <!-- YAML

Diff for: lib/util.js

@@ -89,15 +89,6 @@ function lazyAbortController() {
 
 let internalDeepEqual;
 
-/**
- * @deprecated since v4.0.0
- * @param {any} arg
- * @returns {arg is Function}
- */
-function isFunction(arg) {
-  return typeof arg === 'function';
-}
-
 /**
  * @deprecated since v4.0.0
  * @param {any} arg
@@ -344,9 +335,6 @@ module.exports = {
     }
     return internalDeepEqual(a, b);
   },
-  isFunction: deprecate(isFunction,
-                        'The `util.isFunction` API is deprecated.  Please use `typeof arg === "function"` instead.',
-                        'DEP0049'),
   isPrimitive: deprecate(isPrimitive,
                          'The `util.isPrimitive` API is deprecated. ' +
                          'Please use `arg === null || ' +

Diff for: test/parallel/test-util.js

@@ -57,11 +57,6 @@ assert.strictEqual(util.isPrimitive(Infinity), true);
 assert.strictEqual(util.isPrimitive(NaN), true);
 assert.strictEqual(util.isPrimitive(Symbol('symbol')), true);
 
-assert.strictEqual(util.isFunction(() => {}), true);
-assert.strictEqual(util.isFunction(function() {}), true);
-assert.strictEqual(util.isFunction(), false);
-assert.strictEqual(util.isFunction('string'), false);
-
 assert.strictEqual(util.toUSVString('string\ud801'), 'string\ufffd');
 
 {