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diff --git a/test/lisp/emacs-lisp/derived-tests.el b/test/lisp/emacs-lisp/derived-tests.el
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+++ b/test/lisp/emacs-lisp/derived-tests.el
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+;;; derived-tests.el --- tests for derived.el  -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2017-2022 Free Software Foundation, Inc.
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Code:
+
+(require 'ert)
+
+(define-derived-mode derived-tests--parent-mode prog-mode "P"
+  :after-hook
+  (let ((f (let ((x "S")) (lambda () x))))
+    (insert (format "AFP=%s " (let ((x "D")) x (funcall f)))))
+  (insert "PB "))
+
+(define-derived-mode derived-tests--child-mode derived-tests--parent-mode "C"
+  :after-hook
+  (let ((f (let ((x "S")) (lambda () x))))
+    (insert (format "AFC=%s " (let ((x "D")) x (funcall f)))))
+  (insert "CB "))
+
+(ert-deftest derived-tests-after-hook-lexical ()
+  (with-temp-buffer
+    (let ((derived-tests--child-mode-hook
+           (lambda () (insert "MH "))))
+      (derived-tests--child-mode)
+      (should (equal (buffer-string) "PB CB MH AFP=S AFC=S ")))))
+
+(declare-function mode-a "derived-tests")
+(declare-function mode-b "derived-tests")
+(declare-function mode-c "derived-tests")
+(ert-deftest test-add-font-lock ()
+  (define-derived-mode mode-a fundamental-mode "mode-a"
+    (font-lock-add-keywords nil `(("a" 0 'font-lock-keyword-face))))
+  (define-derived-mode mode-b mode-a "mode-b"
+    (font-lock-add-keywords nil `(("b" 0 'font-lock-builtin-face))))
+  (define-derived-mode mode-c mode-b "mode-c"
+    (font-lock-add-keywords nil `(("c" 0 'font-lock-constant-face))))
+
+  (with-temp-buffer
+    (mode-c)
+    (should (equal font-lock-keywords
+                   '(t (("c" 0 'font-lock-constant-face)
+                        ("b" 0 'font-lock-builtin-face)
+                        ("a" 0 'font-lock-keyword-face))
+                       ("c" (0 'font-lock-constant-face))
+                       ("b" (0 'font-lock-builtin-face))
+                       ("a" (0 'font-lock-keyword-face)))))))
+
+;;; derived-tests.el ends here