Add lexical-binding cookie to generated files

Side-companion to commits bb0f84bc0b and 50947fd512.
While in there, couldn't resist adding a few minor cleanups
I had lying around.

* lisp/savehist.el (savehist-save): Add `lexical-binding:t` cookie.

* lisp/url/url-cookie.el: Remove redundant `:group` arguments.
(url-cookie-write-file): Add `lexical-binding:t` cookie.

* lisp/abbrev.el: Prefer #' to quote function names.
(write-abbrev-file): Add a `lexical-binding:t` cookie.
(unexpand-abbrev): Use `replace-region-contents` and 3-args `<=`.
(define-abbrev-table): Use `defvar-1`.

* lisp/filesets.el (filesets-menu-cache-file-save-maybe):
Add `lexical-binding:t` cookie.
(filesets-ingroup-patterns): Don't quote lambdas.
(filesets-spawn-external-viewer): Remove redundant "" arg to `mapconcat`.

* lisp/recentf.el: Prefer #' to quote function names.
(recentf-save-file-header): Add `lexical-binding:t` cookie and change
mode to match the actual content.

lisp/abbrev.el

@@ -42,7 +42,7 @@
 (defcustom abbrev-file-name
   (locate-user-emacs-file "abbrev_defs" ".abbrev_defs")
   "Default name of file from which to read and where to save abbrevs."
-  :initialize 'custom-initialize-delay
+  :initialize #'custom-initialize-delay
   :type 'file)
 
 (defcustom only-global-abbrevs nil
@@ -62,7 +62,7 @@ be replaced by its expansion."
   ;; defining it again.
   :variable abbrev-mode)
 
-(put 'abbrev-mode 'safe-local-variable 'booleanp)
+(put 'abbrev-mode 'safe-local-variable #'booleanp)
 
 
 (define-obsolete-variable-alias 'edit-abbrevs-map
@@ -271,7 +271,8 @@ abbrevs have been saved."
       (when (unencodable-char-position (point-min) (point-max) 'utf-8)
 	(setq coding-system-for-write 'utf-8-emacs))
       (goto-char (point-min))
-      (insert (format ";;-*-coding: %s;-*-\n" coding-system-for-write))
+      (insert (format ";;-*-coding: %S; lexical-binding:t -*-\n"
+                      coding-system-for-write))
       (write-region nil nil file nil (and (not verbose) 0)))))
 
 (defun abbrev-edit-save-to-file (file)
@@ -495,13 +496,13 @@ A prefix argument means don't query; expand all abbrevs."
     (set sym nil)	     ; Make sure it won't be confused for an abbrev.
     (put sym prop val)))
 
-(defalias 'abbrev-get 'get
+(defalias 'abbrev-get #'get
   "Get the property PROP of abbrev ABBREV
 See `define-abbrev' for the effect of some special properties.
 
 \(fn ABBREV PROP)")
 
-(defalias 'abbrev-put 'put
+(defalias 'abbrev-put #'put
   "Set the property PROP of abbrev ABBREV to value VAL.
 See `define-abbrev' for the effect of some special properties.
 
@@ -574,8 +575,7 @@ This causes `save-some-buffers' to offer to save the abbrevs.")
 
 (defcustom abbrev-all-caps nil
   "Non-nil means expand multi-word abbrevs in all caps if the abbrev was so."
-  :type 'boolean
-  :group 'abbrev-mode)
+  :type 'boolean)
 
 (defvar abbrev-start-location nil
   "Buffer position for `expand-abbrev' to use as the start of the abbrev.
@@ -692,7 +692,7 @@ current (if global is nil) or standard syntax table."
           (cl-pushnew (aref abbrev (match-beginning 0)) badchars)
           (setq pos (1+ pos)))
         (error "Some abbrev characters (%s) are not word constituents %s"
-               (apply 'string (nreverse badchars))
+               (apply #'string (nreverse badchars))
                (if global "in the standard syntax" "in this mode"))))))
 
 (defun define-global-abbrev (abbrev expansion)
@@ -1097,8 +1097,7 @@ This differs from ordinary undo in that other editing done since then
 is not undone."
   (interactive)
   (save-excursion
-    (unless (or (< last-abbrev-location (point-min))
-                (> last-abbrev-location (point-max)))
+    (when (<= (point-min) last-abbrev-location (point-max))
       (goto-char last-abbrev-location)
       (when (stringp last-abbrev-text)
         ;; This isn't correct if last-abbrev's hook was used
@@ -1107,9 +1106,9 @@ is not undone."
           (unless (stringp val)
             (error "Value of abbrev-symbol must be a string"))
           ;; Don't inherit properties here; just copy from old contents.
-          (insert last-abbrev-text)
-          ;; Delete after inserting, to better preserve markers.
-          (delete-region (point) (+ (point) (length val)))
+          (replace-region-contents (point) (+ (point) (length val))
+                                   last-abbrev-text 0)
+          (goto-char (+ (point) (length last-abbrev-text)))
           (setq last-abbrev-text nil))))))
 
 (defun abbrev--write (sym)
@@ -1159,21 +1158,21 @@ a call to `define-abbrev-table' that, when evaluated, will define
 the abbrev table NAME exactly as it is currently defined.
 Abbrevs marked as \"system abbrevs\" are ignored."
   (let ((symbols (abbrev--table-symbols name readable)))
-    (setq symbols (sort symbols 'string-lessp))
+    (setq symbols (sort symbols #'string-lessp))
     (let ((standard-output (current-buffer)))
       (if readable
           (progn
             (insert "(")
             (prin1 name)
             (insert ")\n\n")
-            (mapc 'abbrev--describe symbols)
+            (mapc #'abbrev--describe symbols)
             (insert "\n\n"))
         (insert "(define-abbrev-table '")
         (prin1 name)
         (if (null symbols)
             (insert " '())\n\n")
           (insert "\n  '(\n")
-          (mapc 'abbrev--write symbols)
+          (mapc #'abbrev--write symbols)
           (insert "   ))\n\n")))
       nil)))
 
@@ -1216,7 +1215,7 @@ Properties with special meaning:
     ;; There is really no docstring, instead the docstring arg
     ;; is a property name.
     (push docstring props) (setq docstring nil))
-  (eval `(defvar ,tablename nil ,@(if docstring (list docstring))))
+  (defvar-1 tablename nil docstring)
   (let ((table (if (boundp tablename) (symbol-value tablename))))
     (unless table
       (setq table (make-abbrev-table))
@@ -1230,7 +1229,7 @@ Properties with special meaning:
       (unless (cdr props) (error "Missing value for property %S" (car props)))
       (abbrev-table-put table (pop props) (pop props)))
     (dolist (elt definitions)
-      (apply 'define-abbrev table elt))))
+      (apply #'define-abbrev table elt))))
 
 (defun abbrev-table-menu (table &optional prompt sortfun)
   "Return a menu that shows all abbrevs in TABLE.

lisp/filesets.el

@@ -671,69 +671,70 @@ In order to view pdf or rtf files in an Emacs buffer, you could use these:
 				      (boolean :tag "Boolean")))))))
 
 (defcustom filesets-ingroup-patterns
-  '(("^.+\\.tex$" t
+  ;; FIXME: This value does not seem realistically editable via the Custom UI.
+  `(("^.+\\.tex$" t
      (((:name "Package")
        (:pattern "\\\\usepackage\\W*\\(\\[[^]]*\\]\\W*\\)?{\\W*\\(.+\\)\\W*}")
        (:match-number 2)
        (:stub-flag t)
-       (:get-file-name (lambda (master file)
-			 (filesets-which-file master
-					      (concat file ".sty")
-					      (filesets-convert-path-list
-					       (or (getenv "MY_TEXINPUTS")
-						   (getenv "TEXINPUTS")))))))
+       (:get-file-name ,(lambda (master file)
+			  (filesets-which-file master
+					       (concat file ".sty")
+					       (filesets-convert-path-list
+						(or (getenv "MY_TEXINPUTS")
+						    (getenv "TEXINPUTS")))))))
       ((:name "Include")
        (:pattern "\\\\include\\W*{\\W*\\(.+\\)\\W*}")
-       (:get-file-name (lambda (master file)
-			 (filesets-which-file master
-					      (concat file ".tex")
-					      (filesets-convert-path-list
-					       (or (getenv "MY_TEXINPUTS")
-						   (getenv "TEXINPUTS"))))))
+       (:get-file-name ,(lambda (master file)
+			  (filesets-which-file master
+					       (concat file ".tex")
+					       (filesets-convert-path-list
+						(or (getenv "MY_TEXINPUTS")
+						    (getenv "TEXINPUTS"))))))
        (:scan-depth 5))
       ((:name "Input")
        (:pattern "\\\\input\\W*{\\W*\\(.+\\)\\W*}")
-       (:stubp (lambda (a b) (not (filesets-files-in-same-directory-p a b))))
-       (:get-file-name (lambda (master file)
-			 (filesets-which-file master
-					      (concat file ".tex")
-					      (filesets-convert-path-list
-					       (or (getenv "MY_TEXINPUTS")
-						   (getenv "TEXINPUTS"))))))
+       (:stubp ,(lambda (a b) (not (filesets-files-in-same-directory-p a b))))
+       (:get-file-name ,(lambda (master file)
+			  (filesets-which-file master
+					       (concat file ".tex")
+					       (filesets-convert-path-list
+						(or (getenv "MY_TEXINPUTS")
+						    (getenv "TEXINPUTS"))))))
        (:scan-depth 5))
       ((:name "Bibliography")
        (:pattern "\\\\bibliography\\W*{\\W*\\(.+\\)\\W*}")
-       (:get-file-name (lambda (master file)
-			 (filesets-which-file master
-					      (concat file ".bib")
-					      (filesets-convert-path-list
-					       (or (getenv "MY_BIBINPUTS")
-						   (getenv "BIBINPUTS")))))))))
+       (:get-file-name ,(lambda (master file)
+			  (filesets-which-file master
+					       (concat file ".bib")
+					       (filesets-convert-path-list
+						(or (getenv "MY_BIBINPUTS")
+						    (getenv "BIBINPUTS")))))))))
     ("^.+\\.el$" t
      (((:name "Require")
        (:pattern "(require\\W+'\\(.+\\))")
-       (:stubp (lambda (a b) (not (filesets-files-in-same-directory-p a b))))
-       (:get-file-name (lambda (master file)
-			 (filesets-which-file master
-					      (concat file ".el")
-					      load-path))))
+       (:stubp ,(lambda (a b) (not (filesets-files-in-same-directory-p a b))))
+       (:get-file-name ,(lambda (master file)
+			  (filesets-which-file master
+					       (concat file ".el")
+					       load-path))))
       ((:name "Load")
        (:pattern "(load\\(-library\\)?\\W+\"\\(.+\\)\")")
        (:match-number 2)
-       (:get-file-name (lambda (master file)
-			 (filesets-which-file master file load-path))))))
+       (:get-file-name ,(lambda (master file)
+			  (filesets-which-file master file load-path))))))
     ("^\\([A-ZÄÖÜ][a-zäöüß]+\\([A-ZÄÖÜ][a-zäöüß]+\\)+\\)$" t
      (((:pattern "\\<\\([A-ZÄÖÜ][a-zäöüß]+\\([A-ZÄÖÜ][a-zäöüß]+\\)+\\)\\>")
        (:scan-depth 5)
-       (:stubp (lambda (a b) (not (filesets-files-in-same-directory-p a b))))
+       (:stubp ,(lambda (a b) (not (filesets-files-in-same-directory-p a b))))
        (:case-sensitive t)
-       (:get-file-name (lambda (master file)
-			 (filesets-which-file
-			  master
-			  file
-			  (if (boundp 'emacs-wiki-directories)
-			      emacs-wiki-directories
-			    nil))))))))
+       (:get-file-name ,(lambda (master file)
+			  (filesets-which-file
+			   master
+			   file
+			   (if (boundp 'emacs-wiki-directories)
+			       emacs-wiki-directories
+			     nil))))))))
 
   "Inclusion group definitions.
 
@@ -1227,7 +1228,7 @@ Use the viewer defined in EV-ENTRY (a valid element of
 				(shell-quote-argument (if (functionp this)
 				                          (funcall this)
 				                        this))))
-			    fmt "")
+			    fmt)
 			 (shell-quote-argument file))))
 	       (output
 		(cond
@@ -2335,6 +2336,7 @@ fileset thinks this is necessary or not."
       (delete-file filesets-menu-cache-file))
     ;;(message "Filesets: saving menu cache")
     (with-temp-buffer
+      (insert ";; -*- mode: emacs-lisp; lexical-binding:t -*-\n")
       (dolist (this filesets-menu-cache-contents)
 	(if (get this 'custom-type)
 	    (progn

lisp/recentf.el

@@ -88,7 +88,7 @@ See the command `recentf-save-list'."
   :group 'recentf
   :version "31.1"
   :type 'file
-  :initialize 'custom-initialize-default
+  :initialize #'custom-initialize-default
   :set (lambda (symbol value)
          (let ((oldvalue (symbol-value symbol)))
            (custom-set-default symbol value)
@@ -158,7 +158,7 @@ Set VARIABLE with VALUE, and force a rebuild of the recentf menu."
   "Name of the recentf menu."
   :group 'recentf
   :type 'string
-  :set 'recentf-menu-customization-changed)
+  :set #'recentf-menu-customization-changed)
 
 (defcustom recentf-menu-path '("File")
   "Path where to add the recentf menu.
@@ -166,7 +166,7 @@ If nil add it at top level (see also `easy-menu-add-item')."
   :group 'recentf
   :type '(choice (const :tag "Top Level" nil)
                  (sexp :tag "Menu Path"))
-  :set 'recentf-menu-customization-changed)
+  :set #'recentf-menu-customization-changed)
 
 (defcustom recentf-menu-before "Open File..."
   "Name of the menu before which the recentf menu will be added.
@@ -174,7 +174,7 @@ If nil add it at end of menu (see also `easy-menu-add-item')."
   :group 'recentf
   :type '(choice (string :tag "Name")
                  (const :tag "Last" nil))
-  :set 'recentf-menu-customization-changed)
+  :set #'recentf-menu-customization-changed)
 
 (defcustom recentf-menu-action #'find-file
   "Function to invoke with a filename item of the recentf menu.
@@ -391,11 +391,11 @@ See also the option `recentf-auto-cleanup'.")
             nil)
            ((numberp recentf-auto-cleanup)
             (run-with-idle-timer
-             recentf-auto-cleanup t 'recentf-cleanup))
+             recentf-auto-cleanup t #'recentf-cleanup))
            ((stringp recentf-auto-cleanup)
             (run-at-time
              ;; Repeat every 24 hours.
-             recentf-auto-cleanup (* 24 60 60) 'recentf-cleanup))))))
+             recentf-auto-cleanup (* 24 60 60) #'recentf-cleanup))))))
 
 ;;; File functions
 ;;
@@ -508,7 +508,7 @@ Enable `recentf-mode' if it isn't already."
     (funcall recentf-menu-action file)))
 
 ;;;###autoload
-(defalias 'recentf 'recentf-open)
+(defalias 'recentf #'recentf-open)
 
 
 ;;; Menu building
@@ -1316,7 +1316,9 @@ Optional argument N must be a valid digit number.  It defaults to 1.
 ;;; Save/load/cleanup the recent list
 ;;
 (defconst recentf-save-file-header
-  ";;; Automatically generated by `recentf' on %s.  -*- mode: lisp-data -*-\n"
+  ;; FIXME: This should arguably be a `lisp-data' file, but currently
+  ;; it contains and is used as an executable ELisp code.
+  ";;; Automatically generated by `recentf' on %s  -*- mode: emacs-lisp; lexical-binding:t -*-\n"
   "Header to be written into the `recentf-save-file'.")
 
 (defconst recentf-save-file-coding-system

lisp/savehist.el

@@ -244,7 +244,7 @@ If AUTO-SAVE is non-nil, compare the saved contents to the one last saved,
     (insert
      (format-message
       (concat
-       ";; -*- mode: emacs-lisp; coding: %s -*-\n"
+       ";; -*- mode: emacs-lisp; lexical-binding:t; coding: %s -*-\n"
        ";; Minibuffer history file, automatically generated by `savehist'.\n"
        "\n")
       savehist-coding-system))

lisp/url/url-cookie.el

@@ -56,16 +56,14 @@
 
 (defcustom url-cookie-confirmation nil
   "If non-nil, confirmation by the user is required to accept HTTP cookies."
-  :type 'boolean
-  :group 'url-cookie)
+  :type 'boolean)
 
 (defcustom url-cookie-multiple-line nil
   "If nil, HTTP requests put all cookies for the server on one line.
 Some web servers, such as https://www.hotmail.com/, only accept cookies
 when they are on one line.  This is broken behavior, but just try
 telling Microsoft that."
-  :type 'boolean
-  :group 'url-cookie)
+  :type 'boolean)
 
 (defvar url-cookies-changed-since-last-save nil
   "Whether the cookies list has changed since the last save operation.")
@@ -152,7 +150,7 @@ i.e. 1970-1-1) are loaded as expiring one year from now instead."
     (url-cookie-clean-up)
     (url-cookie-clean-up t)
     (with-temp-buffer
-      (insert ";; Emacs-W3 HTTP cookies file\n"
+      (insert ";; Emacs-W3 HTTP cookies file  -*- lexical-binding:t -*-\n"
 	      ";; Automatically generated file!!! DO NOT EDIT!!!\n\n"
 	      "(setq url-cookie-storage\n '")
       (let ((print-length nil) (print-level nil))
@@ -266,13 +264,11 @@ i.e. 1970-1-1) are loaded as expiring one year from now instead."
 
 (defcustom url-cookie-trusted-urls nil
   "A list of regular expressions matching URLs to always accept cookies from."
-  :type '(repeat regexp)
-  :group 'url-cookie)
+  :type '(repeat regexp))
 
 (defcustom url-cookie-untrusted-urls nil
   "A list of regular expressions matching URLs to never accept cookies from."
-  :type '(repeat regexp)
-  :group 'url-cookie)
+  :type '(repeat regexp))
 
 (defun url-cookie-host-can-set-p (host domain)
   (cond
@@ -361,8 +357,7 @@ to run the `url-cookie-setup-save-timer' function manually."
          (set-default var val)
          (if (bound-and-true-p url-setup-done)
              (url-cookie-setup-save-timer)))
-  :type 'natnum
-  :group 'url-cookie)
+  :type 'natnum)
 
 (defun url-cookie-setup-save-timer ()
   "Reset the cookie saver timer."