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compat-27.el (37106B)


      1 ;;; compat-27.el --- Functionality added in Emacs 27.1 -*- lexical-binding: t; -*-
      2 
      3 ;; Copyright (C) 2021-2024 Free Software Foundation, Inc.
      4 
      5 ;; This program is free software; you can redistribute it and/or modify
      6 ;; it under the terms of the GNU General Public License as published by
      7 ;; the Free Software Foundation, either version 3 of the License, or
      8 ;; (at your option) any later version.
      9 
     10 ;; This program is distributed in the hope that it will be useful,
     11 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
     12 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     13 ;; GNU General Public License for more details.
     14 
     15 ;; You should have received a copy of the GNU General Public License
     16 ;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
     17 
     18 ;;; Commentary:
     19 
     20 ;; Functionality added in Emacs 27.1, needed by older Emacs versions.
     21 
     22 ;;; Code:
     23 
     24 (eval-when-compile (load "compat-macs.el" nil t t))
     25 (compat-require compat-26 "26.1")
     26 
     27 (compat-version "27.1")
     28 
     29 ;;;; Defined in fns.c
     30 
     31 (compat-defun proper-list-p (object) ;; <compat-tests:proper-list-p>
     32   "Return OBJECT's length if it is a proper list, nil otherwise.
     33 A proper list is neither circular nor dotted (i.e., its last cdr
     34 is nil)."
     35   (if (eval-when-compile (< emacs-major-version 26))
     36       ;; On older Emacs than 26.1 use Tortoise and Hare algorithm
     37       (when (listp object)
     38         (catch 'cycle
     39           (let ((hare object) (tortoise object)
     40                 (max 2) (q 2))
     41             (while (consp hare)
     42               (setq hare (cdr hare))
     43               (when (and (or (/= 0 (setq q (1- q)))
     44                              (ignore
     45                               (setq max (ash max 1)
     46                                     q max
     47                                     tortoise hare)))
     48                          (eq hare tortoise))
     49                 (throw 'cycle nil)))
     50             (and (null hare) (length object)))))
     51     ;; Errors on 26.1 and newer
     52     (and (listp object) (ignore-errors (length object)))))
     53 
     54 (compat-defun string-distance (string1 string2 &optional bytecompare) ;; <compat-tests:string-distance>
     55   "Return Levenshtein distance between STRING1 and STRING2.
     56 The distance is the number of deletions, insertions, and substitutions
     57 required to transform STRING1 into STRING2.
     58 If BYTECOMPARE is nil or omitted, compute distance in terms of characters.
     59 If BYTECOMPARE is non-nil, compute distance in terms of bytes.
     60 Letter-case is significant, but text properties are ignored."
     61   ;; https://en.wikipedia.org/wiki/Levenshtein_distance
     62   (let ((s1 (if bytecompare
     63                 (encode-coding-string string1 'raw-text)
     64               (concat string1 "")))
     65         (s2 (if bytecompare
     66                 (encode-coding-string string2 'raw-text)
     67               string2)))
     68     (let* ((len1 (length s1))
     69            (len2 (length s2))
     70            (column (make-vector (1+ len1) 0)))
     71       (dotimes (y len1)
     72         (setf (aref column (1+ y)) y))
     73       (dotimes (x len2)
     74         (setf (aref column 0) (1+ x))
     75         (let ((lastdiag x) olddiag)
     76           (dotimes (y len1)
     77             (setf olddiag (aref column (1+ y))
     78                   (aref column (1+ y))
     79                   (min (+ (if (= (aref s1 y) (aref s2 x)) 0 1)
     80                           lastdiag)
     81                        (1+ (aref column (1+ y)))
     82                        (1+ (aref column y)))
     83                   lastdiag olddiag))))
     84       (aref column len1))))
     85 
     86 ;;;; Defined in window.c
     87 
     88 (compat-defun recenter (&optional arg redisplay) ;; <compat-tests:recenter>
     89   "Handle optional argument REDISPLAY."
     90   :extended t
     91   (recenter arg)
     92   (when (and redisplay recenter-redisplay)
     93     (redisplay)))
     94 
     95 ;;;; Defined in keymap.c
     96 
     97 (compat-defun lookup-key (keymap key &optional accept-default) ;; <compat-tests:lookup-key>
     98   "Allow for KEYMAP to be a list of keymaps."
     99   :extended t
    100   (cond
    101    ((keymapp keymap)
    102     (lookup-key keymap key accept-default))
    103    ((listp keymap)
    104     (catch 'found
    105       (dolist (map keymap)
    106         (when-let ((fn (lookup-key map key accept-default)))
    107           (throw 'found fn)))))
    108    ((signal 'wrong-type-argument (list 'keymapp keymap)))))
    109 
    110 ;;;; Defined in timefns.c
    111 
    112 (compat-defun time-equal-p (t1 t2) ;; <compat-tests:time-equal-p>
    113   "Return non-nil if time value T1 is equal to time value T2.
    114 A nil value for either argument stands for the current time.
    115 
    116 NOTE: This function is not as accurate as the actual `time-equal-p'."
    117   (cond
    118    ((eq t1 t2))
    119    ((and (consp t1) (consp t2))
    120     (equal t1 t2))
    121    (t
    122     ;; Due to inaccuracies and the relatively slow evaluating of
    123     ;; Emacs Lisp compared to C, we allow for slight inaccuracies
    124     ;; (less than a millisecond) when comparing time values.
    125     (< (abs (- (float-time t1) (float-time t2)))
    126        (if (and t1 t2) 1e-6 1e-5)))))
    127 
    128 ;;;; Defined in subr.el
    129 
    130 (compat-defalias fixnump integerp) ;; <compat-tests:fixnump>
    131 (compat-defalias bignump ignore) ;; <compat-tests:bignump>
    132 
    133 (compat-defmacro setq-local (&rest pairs) ;; <compat-tests:setq-local>
    134   "Handle multiple assignments."
    135   :extended t
    136   (unless (zerop (mod (length pairs) 2))
    137     (error "PAIRS must have an even number of variable/value members"))
    138   (let (body)
    139     (while pairs
    140       (let* ((sym (pop pairs))
    141              (val (pop pairs)))
    142         (unless (symbolp sym)
    143           (error "Attempting to set a non-symbol: %s" (car pairs)))
    144         (push `(set (make-local-variable ',sym) ,val)
    145               body)))
    146     (cons 'progn (nreverse body))))
    147 
    148 (compat-defmacro ignore-error (condition &rest body) ;; <compat-tests:ignore-error>
    149   "Execute BODY; if the error CONDITION occurs, return nil.
    150 Otherwise, return result of last form in BODY.
    151 
    152 CONDITION can also be a list of error conditions."
    153   (declare (debug t) (indent 1))
    154   `(condition-case nil (progn ,@body) (,condition nil)))
    155 
    156 (compat-defmacro dolist-with-progress-reporter (spec reporter-or-message &rest body) ;; <compat-tests:dolist-with-progress-reporter>
    157   "Loop over a list and report progress in the echo area.
    158 Evaluate BODY with VAR bound to each car from LIST, in turn.
    159 Then evaluate RESULT to get return value, default nil.
    160 
    161 REPORTER-OR-MESSAGE is a progress reporter object or a string.  In the latter
    162 case, use this string to create a progress reporter.
    163 
    164 At each iteration, print the reporter message followed by progress
    165 percentage in the echo area.  After the loop is finished,
    166 print the reporter message followed by the word \"done\".
    167 
    168 \(fn (VAR LIST [RESULT]) REPORTER-OR-MESSAGE BODY...)"
    169   (declare (indent 2) (debug ((symbolp form &optional form) form body)))
    170   (let ((prep (make-symbol "--dolist-progress-reporter--"))
    171         (count (make-symbol "--dolist-count--"))
    172         (list (make-symbol "--dolist-list--")))
    173     `(let ((,prep ,reporter-or-message)
    174            (,count 0)
    175            (,list ,(cadr spec)))
    176        (when (stringp ,prep)
    177          (setq ,prep (make-progress-reporter ,prep 0 (length ,list))))
    178        (dolist (,(car spec) ,list)
    179          ,@body
    180          (progress-reporter-update ,prep (setq ,count (1+ ,count))))
    181        (progress-reporter-done ,prep)
    182        (or ,@(cdr (cdr spec)) nil))))
    183 
    184 (compat-defun flatten-tree (tree) ;; <compat-tests:flatten-tree>
    185   "Return a \"flattened\" copy of TREE.
    186 In other words, return a list of the non-nil terminal nodes, or
    187 leaves, of the tree of cons cells rooted at TREE.  Leaves in the
    188 returned list are in the same order as in TREE.
    189 
    190 \(flatten-tree \\='(1 (2 . 3) nil (4 5 (6)) 7))
    191 => (1 2 3 4 5 6 7)"
    192   (let (elems)
    193     (while (consp tree)
    194       (let ((elem (pop tree)))
    195         (while (consp elem)
    196           (push (cdr elem) tree)
    197           (setq elem (car elem)))
    198         (if elem (push elem elems))))
    199     (if tree (push tree elems))
    200     (nreverse elems)))
    201 
    202 (compat-defun xor (cond1 cond2) ;; <compat-tests:xor>
    203   "Return the boolean exclusive-or of COND1 and COND2.
    204 If only one of the arguments is non-nil, return it; otherwise
    205 return nil."
    206   (declare (pure t) (side-effect-free error-free))
    207   (cond ((not cond1) cond2)
    208         ((not cond2) cond1)))
    209 
    210 (compat-defvar regexp-unmatchable "\\`a\\`" ;; <compat-tests:regexp-unmatchable>
    211   "Standard regexp guaranteed not to match any string at all."
    212   :constant t)
    213 
    214 (compat-defun assoc-delete-all (key alist &optional test) ;; <compat-tests:assoc-delete-all>
    215   "Handle optional argument TEST."
    216   :extended "26.2"
    217   (unless test (setq test #'equal))
    218   (while (and (consp (car alist))
    219               (funcall test (caar alist) key))
    220     (setq alist (cdr alist)))
    221   (let ((tail alist) tail-cdr)
    222     (while (setq tail-cdr (cdr tail))
    223       (if (and (consp (car tail-cdr))
    224                (funcall test (caar tail-cdr) key))
    225           (setcdr tail (cdr tail-cdr))
    226         (setq tail tail-cdr))))
    227   alist)
    228 
    229 (compat-defvar major-mode--suspended nil ;; <compat-tests:major-mode-suspend>
    230   "Suspended major mode."
    231   :local permanent)
    232 
    233 (compat-defun major-mode-suspend () ;; <compat-tests:major-mode-suspend>
    234   "Exit current major mode, remembering it."
    235   (let* ((prev-major-mode (or major-mode--suspended
    236                               (unless (eq major-mode 'fundamental-mode)
    237                                 major-mode))))
    238     (kill-all-local-variables)
    239     (setq-local major-mode--suspended prev-major-mode)))
    240 
    241 (compat-defun major-mode-restore (&optional avoided-modes) ;; <compat-tests:major-mode-suspend>
    242   "Restore major mode earlier suspended with `major-mode-suspend'.
    243 If there was no earlier suspended major mode, then fallback to `normal-mode',
    244 though trying to avoid AVOIDED-MODES."
    245   (if major-mode--suspended
    246       (funcall (prog1 major-mode--suspended
    247                  (kill-local-variable 'major-mode--suspended)))
    248     (let ((auto-mode-alist
    249            (let ((alist (copy-sequence auto-mode-alist)))
    250              (dolist (mode avoided-modes)
    251                (setq alist (rassq-delete-all mode alist)))
    252              alist))
    253           (magic-fallback-mode-alist
    254            (let ((alist (copy-sequence magic-fallback-mode-alist)))
    255              (dolist (mode avoided-modes)
    256                (setq alist (rassq-delete-all mode alist)))
    257              alist)))
    258       (normal-mode))))
    259 
    260 (compat-defun read-char-from-minibuffer-insert-char () ;; <compat-tests:read-char-from-minibuffer>
    261   "Insert the character you type into the minibuffer and exit minibuffer.
    262 Discard all previous input before inserting and exiting the minibuffer."
    263   (interactive)
    264   (when (minibufferp)
    265     (delete-minibuffer-contents)
    266     (insert last-command-event)
    267     (exit-minibuffer)))
    268 
    269 (compat-defun read-char-from-minibuffer-insert-other () ;; <compat-tests:read-char-from-minibuffer>
    270   "Reject a disallowed character typed into the minibuffer.
    271 This command is intended to be bound to keys that users are not
    272 allowed to type into the minibuffer.  When the user types any
    273 such key, this command discard all minibuffer input and displays
    274 an error message."
    275   (interactive)
    276   (when (minibufferp)
    277     (delete-minibuffer-contents)
    278     (ding)
    279     (discard-input)
    280     (minibuffer-message "Wrong answer")
    281     (sit-for 2)))
    282 
    283 (compat-defvar read-char-history nil ;; <compat-tests:read-char-from-minibuffer>
    284   "The default history for the `read-char-from-minibuffer' function.")
    285 
    286 (compat-defvar read-char-from-minibuffer-map ;; <compat-tests:read-char-from-minibuffer>
    287   (let ((map (make-sparse-keymap)))
    288     (set-keymap-parent map minibuffer-local-map)
    289     (define-key map [remap self-insert-command] #'read-char-from-minibuffer-insert-char)
    290     (define-key map [remap exit-minibuffer] #'read-char-from-minibuffer-insert-other)
    291     map)
    292   "Keymap for the `read-char-from-minibuffer' function.")
    293 
    294 (compat-defvar read-char-from-minibuffer-map-hash  ;; <compat-tests:read-char-from-minibuffer>
    295   (make-hash-table :test 'equal)
    296   "Hash table of keymaps used by `read-char-from-minibuffer'."
    297   :constant t)
    298 
    299 (compat-defun read-char-from-minibuffer (prompt &optional chars history) ;; <compat-tests:read-char-from-minibuffer>
    300   "Read a character from the minibuffer, prompting for it with PROMPT.
    301 Like `read-char', but uses the minibuffer to read and return a character.
    302 Optional argument CHARS, if non-nil, should be a list of characters;
    303 the function will ignore any input that is not one of CHARS.
    304 Optional argument HISTORY, if non-nil, should be a symbol that
    305 specifies the history list variable to use for navigating in input
    306 history using \\`M-p' and \\`M-n', with \\`RET' to select a character from
    307 history.
    308 If you bind the variable `help-form' to a non-nil value
    309 while calling this function, then pressing `help-char'
    310 causes it to evaluate `help-form' and display the result.
    311 There is no need to explicitly add `help-char' to CHARS;
    312 `help-char' is bound automatically to `help-form-show'."
    313   (let* ((map (if (consp chars)
    314                   (or (gethash (list help-form (cons help-char chars))
    315                                read-char-from-minibuffer-map-hash)
    316                       (let ((map (make-sparse-keymap))
    317                             (msg help-form))
    318                         (set-keymap-parent map read-char-from-minibuffer-map)
    319                         ;; If we have a dynamically bound `help-form'
    320                         ;; here, then the `C-h' (i.e., `help-char')
    321                         ;; character should output that instead of
    322                         ;; being a command char.
    323                         (when help-form
    324                           (define-key map (vector help-char)
    325                             (lambda ()
    326                               (interactive)
    327                               (let ((help-form msg)) ; lexically bound msg
    328                                 (help-form-show)))))
    329                         (dolist (char chars)
    330                           (define-key map (vector char)
    331                             #'read-char-from-minibuffer-insert-char))
    332                         (define-key map [remap self-insert-command]
    333                           #'read-char-from-minibuffer-insert-other)
    334                         (puthash (list help-form (cons help-char chars))
    335                                  map read-char-from-minibuffer-map-hash)
    336                         map))
    337                 read-char-from-minibuffer-map))
    338          ;; Protect this-command when called from pre-command-hook (bug#45029)
    339          (this-command this-command)
    340          (result (read-from-minibuffer prompt nil map nil (or history t)))
    341          (char
    342           (if (> (length result) 0)
    343               ;; We have a string (with one character), so return the first one.
    344               (elt result 0)
    345             ;; The default value is RET.
    346             (when history (push "\r" (symbol-value history)))
    347             ?\r)))
    348     ;; Display the question with the answer.
    349     (message "%s%s" prompt (char-to-string char))
    350     char))
    351 
    352 ;;;; Defined in simple.el
    353 
    354 (compat-guard (not (fboundp 'decoded-time-second)) ;; <compat-tests:decoded-time>
    355   (cl-defstruct (decoded-time
    356                  (:constructor nil)
    357                  (:copier nil)
    358                  (:type list))
    359     (second nil :documentation "\
    360 This is an integer or a Lisp timestamp (TICKS . HZ) representing a nonnegative
    361 number of seconds less than 61.  (If not less than 60, it is a leap second,
    362 which only some operating systems support.)")
    363     (minute nil :documentation "This is an integer between 0 and 59 (inclusive).")
    364     (hour nil :documentation "This is an integer between 0 and 23 (inclusive).")
    365     (day nil :documentation "This is an integer between 1 and 31 (inclusive).")
    366     (month nil :documentation "\
    367 This is an integer between 1 and 12 (inclusive).  January is 1.")
    368     (year nil :documentation "This is a four digit integer.")
    369     (weekday nil :documentation "\
    370 This is a number between 0 and 6, and 0 is Sunday.")
    371     (dst -1 :documentation "\
    372 This is t if daylight saving time is in effect, nil if it is not
    373 in effect, and -1 if daylight saving information is not available.
    374 Also see `decoded-time-dst'.")
    375     (zone nil :documentation "\
    376 This is an integer indicating the UTC offset in seconds, i.e.,
    377 the number of seconds east of Greenwich.")))
    378 
    379 (compat-defun minibuffer-history-value () ;; <compat-tests:minibuffer-history-value>
    380   "Return the value of the minibuffer input history list.
    381 If `minibuffer-history-variable' points to a buffer-local variable and
    382 the minibuffer is active, return the buffer-local value for the buffer
    383 that was current when the minibuffer was activated."
    384   (buffer-local-value minibuffer-history-variable
    385                       (window-buffer (minibuffer-selected-window))))
    386 
    387 ;;;; Defined in minibuffer.el
    388 
    389 (compat-defmacro with-minibuffer-selected-window (&rest body) ;; <compat-tests:with-minibuffer-selected-window>
    390   "Execute the forms in BODY from the minibuffer in its original window.
    391 When used in a minibuffer window, select the window selected just before
    392 the minibuffer was activated, and execute the forms."
    393   (declare (indent 0) (debug t))
    394   `(when-let ((window (minibuffer-selected-window)))
    395      (with-selected-window window
    396        ,@body)))
    397 
    398 ;;;; Defined in byte-run.el
    399 
    400 (compat-defmacro with-suppressed-warnings (_warnings &rest body) ;; <compat-tests:with-suppressed-warnings>
    401   "Like `progn', but prevents compiler WARNINGS in BODY.
    402 NOTE: The compatibility version behaves like `with-no-warnings'."
    403   `(with-no-warnings ,@body))
    404 
    405 ;;;; Defined in image.el
    406 
    407 (compat-defun image--set-property (image property value) ;; <compat-tests:image-property>
    408   "Set PROPERTY in IMAGE to VALUE, internal use only."
    409   :extended "26.1"
    410   :feature image
    411   (if (null value)
    412       (while (cdr image)
    413         (if (eq (cadr image) property)
    414             (setcdr image (cdddr image))
    415           (setq image (cddr image))))
    416     (setcdr image (plist-put (cdr image) property value)))
    417   value)
    418 
    419 ;; HACK: image--set-property was broken with an off-by-one error on Emacs 26.
    420 ;; The bug was fixed in a4ad7bed187493c1c230f223b52c71f5c34f7c89. Therefore we
    421 ;; override the gv expander until Emacs 27.1.
    422 (compat-guard ;; <compat-tests:image-property>
    423     (or (= emacs-major-version 26) (not (get 'image-property 'gv-expander)))
    424   :feature image
    425   (gv-define-setter image-property (value image prop)
    426     `(,(if (< emacs-major-version 26) 'image--set-property 'compat--image--set-property)
    427       ,image ,prop ,value)))
    428 
    429 ;;;; Defined in files.el
    430 
    431 (compat-defun file-name-quoted-p (name &optional top) ;; <compat-tests:file-name-quoted-p>
    432   "Handle optional argument TOP."
    433   :extended "26.1"
    434   (let ((file-name-handler-alist (unless top file-name-handler-alist)))
    435     (string-prefix-p "/:" (file-local-name name))))
    436 
    437 (compat-defun file-name-quote (name &optional top) ;; <compat-tests:file-name-quote>
    438   "Handle optional argument TOP."
    439   :extended "26.1"
    440   (let* ((file-name-handler-alist (unless top file-name-handler-alist))
    441          (localname (file-local-name name)))
    442     (if (string-prefix-p "/:" localname)
    443         name
    444       (concat (file-remote-p name) "/:" localname))))
    445 
    446 (compat-defun file-name-unquote (name &optional top) ;; <compat-tests:file-name-unquote>
    447   "Handle optional argument TOP."
    448   :extended "26.1"
    449   (let* ((file-name-handler-alist (unless top file-name-handler-alist))
    450          (localname (file-local-name name)))
    451     (when (string-prefix-p "/:" localname)
    452       (setq localname (if (= (length localname) 2) "/" (substring localname 2))))
    453     (concat (file-remote-p name) localname)))
    454 
    455 (compat-defun file-size-human-readable (file-size &optional flavor space unit) ;; <compat-tests:file-size-human-readable>
    456   "Handle the optional arguments SPACE and UNIT."
    457   :extended t
    458   (let ((power (if (or (null flavor) (eq flavor 'iec))
    459                    1024.0
    460                  1000.0))
    461         (prefixes '("" "k" "M" "G" "T" "P" "E" "Z" "Y")))
    462     (while (and (>= file-size power) (cdr prefixes))
    463       (setq file-size (/ file-size power)
    464             prefixes (cdr prefixes)))
    465     (let* ((prefix (car prefixes))
    466            (prefixed-unit (if (eq flavor 'iec)
    467                               (concat
    468                                (if (string= prefix "k") "K" prefix)
    469                                (if (string= prefix "") "" "i")
    470                                (or unit "B"))
    471                             (concat prefix unit))))
    472       (format (if (and (>= (mod file-size 1.0) 0.05)
    473                        (< (mod file-size 1.0) 0.95))
    474                   "%.1f%s%s"
    475                 "%.0f%s%s")
    476               file-size
    477               (if (string= prefixed-unit "") "" (or space ""))
    478               prefixed-unit))))
    479 
    480 (compat-defun file-size-human-readable-iec (size) ;; <compat-tests:file-size-human-readable-iec>
    481   "Human-readable string for SIZE bytes, using IEC prefixes."
    482   (compat--file-size-human-readable size 'iec " "))
    483 
    484 (compat-defun exec-path () ;; <compat-tests:exec-path>
    485   "Return list of directories to search programs to run in remote subprocesses.
    486 The remote host is identified by `default-directory'.  For remote
    487 hosts that do not support subprocesses, this returns nil.
    488 If `default-directory' is a local directory, this function returns
    489 the value of the variable `exec-path'."
    490   (let ((handler (find-file-name-handler default-directory 'exec-path)))
    491     ;; NOTE: The handler may fail since it was added in 27.1.
    492     (or (and handler (ignore-errors (funcall handler 'exec-path)))
    493         (if (file-remote-p default-directory)
    494             ;; FIXME: Just return some standard path on remote
    495             '("/bin" "/usr/bin" "/sbin" "/usr/sbin" "/usr/local/bin" "/usr/local/sbin")
    496           exec-path))))
    497 
    498 (compat-defun executable-find (command &optional remote) ;; <compat-tests:executable-find>
    499   "Handle optional argument REMOTE."
    500   :extended t
    501   (if (and remote (file-remote-p default-directory))
    502       (let ((res (locate-file
    503                   command
    504                   (mapcar
    505                    (apply-partially
    506                     #'concat (file-remote-p default-directory))
    507                    (exec-path))
    508                   exec-suffixes 'file-executable-p)))
    509         (when (stringp res) (file-local-name res)))
    510     (executable-find command)))
    511 
    512 (compat-defun make-empty-file (filename &optional parents) ;; <compat-tests:make-empty-file>
    513   "Create an empty file FILENAME.
    514 Optional arg PARENTS, if non-nil then creates parent dirs as needed."
    515   (when (and (file-exists-p filename) (null parents))
    516     (signal 'file-already-exists (list "File exists" filename)))
    517   (let ((paren-dir (file-name-directory filename)))
    518     (when (and paren-dir (not (file-exists-p paren-dir)))
    519       (make-directory paren-dir parents)))
    520   (write-region "" nil filename nil 0))
    521 
    522 ;;;; Defined in regexp-opt.el
    523 
    524 (compat-defun regexp-opt (strings &optional paren) ;; <compat-tests:regexp-opt>
    525   "Handle an empty list of STRINGS."
    526   :extended t
    527   (if (null strings)
    528       (let ((re "\\`a\\`"))
    529         (cond ((null paren)
    530                (concat "\\(?:" re "\\)"))
    531               ((stringp paren)
    532                (concat paren re "\\)"))
    533               ((eq paren 'words)
    534                (concat "\\<\\(" re "\\)\\>"))
    535               ((eq paren 'symbols)
    536                (concat "\\_\\(<" re "\\)\\_>"))
    537               ((concat "\\(" re "\\)"))))
    538     (regexp-opt strings paren)))
    539 
    540 ;;;; Defined in package.el
    541 
    542 (declare-function lm-header "lisp-mnt")
    543 (declare-function macroexp-file-name nil)
    544 
    545 (compat-defun package-get-version () ;; <compat-tests:package-get-version>
    546   "Return the version number of the package in which this is used.
    547 Assumes it is used from an Elisp file placed inside the top-level directory
    548 of an installed ELPA package.
    549 The return value is a string (or nil in case we can’t find it)."
    550   ;; No :feature since the function is autoloaded.
    551   ;; In a sense, this is a lie, but it does just what we want: precompute
    552   ;; the version at compile time and hardcodes it into the .elc file!
    553   (declare (pure t))
    554   ;; Hack alert!
    555   (let ((file (or (macroexp-file-name) buffer-file-name)))
    556     (cond
    557      ((null file) nil)
    558      ;; Packages are normally installed into directories named "<pkg>-<vers>",
    559      ;; so get the version number from there.
    560      ((string-match
    561        "/[^/]+-\\([0-9]\\(?:[0-9.]\\|pre\\|beta\\|alpha\\|snapshot\\)+\\)/[^/]+\\'"
    562        file)
    563       (match-string 1 file))
    564      ;; For packages run straight from the an elpa.git clone, there's no
    565      ;; "-<vers>" in the directory name, so we have to fetch the version
    566      ;; the hard way.
    567      ((let* ((pkgdir (file-name-directory file))
    568              (pkgname (file-name-nondirectory (directory-file-name pkgdir)))
    569              (mainfile (expand-file-name (concat pkgname ".el") pkgdir)))
    570         (when (file-readable-p mainfile)
    571           (require 'lisp-mnt)
    572           (with-temp-buffer
    573             (insert-file-contents mainfile)
    574             (or (lm-header "package-version")
    575                 (lm-header "version")))))))))
    576 
    577 ;;;; Defined in time-date.el
    578 
    579 (compat-defun make-decoded-time ;; <compat-tests:make-decoded-time>
    580               (&key second minute hour day month year (dst -1) zone)
    581   "Return a `decoded-time' structure with only the keywords given filled out."
    582   :feature time-date
    583   (list second minute hour day month year nil dst zone))
    584 
    585 (compat-defun date-days-in-month (year month) ;; <compat-tests:date-days-in-month>
    586   "The number of days in MONTH in YEAR."
    587   :feature time-date
    588   (unless (and (numberp month)
    589                (<= 1 month)
    590                (<= month 12))
    591     (error "Month %s is invalid" month))
    592   (if (= month 2)
    593       (if (date-leap-year-p year)
    594           29
    595         28)
    596     (if (memq month '(1 3 5 7 8 10 12))
    597         31
    598       30)))
    599 
    600 (compat-defun date-ordinal-to-time (year ordinal) ;; <compat-tests:date-ordinal-to-time>
    601   "Convert a YEAR/ORDINAL to the equivalent `decoded-time' structure.
    602 ORDINAL is the number of days since the start of the year, with
    603 January 1st being 1."
    604   (let ((month 1))
    605     (while (> ordinal (date-days-in-month year month))
    606       (setq ordinal (- ordinal (date-days-in-month year month))
    607             month (1+ month)))
    608     (list nil nil nil ordinal month year nil nil nil)))
    609 
    610 ;;;; Defined in text-property-search.el
    611 
    612 (declare-function make-prop-match nil)
    613 (compat-guard (not (fboundp 'make-prop-match)) ;; <compat-tests:prop-match>
    614   (cl-defstruct (prop-match) beginning end value))
    615 
    616 (compat-defun text-property-search-forward ;; <compat-tests:text-property-search-forward>
    617     (property &optional value predicate not-current)
    618   "Search for the next region of text where PREDICATE is true.
    619 PREDICATE is used to decide whether a value of PROPERTY should be
    620 considered as matching VALUE.
    621 
    622 If PREDICATE is a function, it will be called with two arguments:
    623 VALUE and the value of PROPERTY.  The function should return
    624 non-nil if these two values are to be considered a match.
    625 
    626 Two special values of PREDICATE can also be used:
    627 If PREDICATE is t, that means a value must `equal' VALUE to be
    628 considered a match.
    629 If PREDICATE is nil (which is the default value), a value will
    630 match if is not `equal' to VALUE.  Furthermore, a nil PREDICATE
    631 means that the match region is ended if the value changes.  For
    632 instance, this means that if you loop with
    633 
    634   (while (setq prop (text-property-search-forward \\='face))
    635     ...)
    636 
    637 you will get all distinct regions with non-nil `face' values in
    638 the buffer, and the `prop' object will have the details about the
    639 match.  See the manual for more details and examples about how
    640 VALUE and PREDICATE interact.
    641 
    642 If NOT-CURRENT is non-nil, the function will search for the first
    643 region that doesn't include point and has a value of PROPERTY
    644 that matches VALUE.
    645 
    646 If no matches can be found, return nil and don't move point.
    647 If found, move point to the end of the region and return a
    648 `prop-match' object describing the match.  To access the details
    649 of the match, use `prop-match-beginning' and `prop-match-end' for
    650 the buffer positions that limit the region, and
    651 `prop-match-value' for the value of PROPERTY in the region."
    652   (let* ((match-p
    653           (lambda (prop-value)
    654             (funcall
    655              (cond
    656               ((eq predicate t)
    657                #'equal)
    658               ((eq predicate nil)
    659                (lambda (val p-val)
    660                  (not (equal val p-val))))
    661               (predicate))
    662              value prop-value)))
    663          (find-end
    664           (lambda (start)
    665             (let (end)
    666               (if (and value
    667                        (null predicate))
    668                   ;; This is the normal case: We're looking for areas where the
    669                   ;; values aren't, so we aren't interested in sub-areas where the
    670                   ;; property has different values, all non-matching value.
    671                   (let ((ended nil))
    672                     (while (not ended)
    673                       (setq end (next-single-property-change (point) property))
    674                       (if (not end)
    675                           (progn
    676                             (goto-char (point-max))
    677                             (setq end (point)
    678                                   ended t))
    679                         (goto-char end)
    680                         (unless (funcall match-p (get-text-property (point) property))
    681                           (setq ended t)))))
    682                 ;; End this at the first place the property changes value.
    683                 (setq end (next-single-property-change (point) property nil (point-max)))
    684                 (goto-char end))
    685               (make-prop-match
    686                :beginning start
    687                :end end
    688                :value (get-text-property start property))))))
    689     (cond
    690      ;; No matches at the end of the buffer.
    691      ((eobp)
    692       nil)
    693      ;; We're standing in the property we're looking for, so find the
    694      ;; end.
    695      ((and (funcall match-p (get-text-property (point) property))
    696            (not not-current))
    697       (funcall find-end (point)))
    698      (t
    699       (let ((origin (point))
    700             (ended nil)
    701             pos)
    702         ;; Find the next candidate.
    703         (while (not ended)
    704           (setq pos (next-single-property-change (point) property))
    705           (if (not pos)
    706               (progn
    707                 (goto-char origin)
    708                 (setq ended t))
    709             (goto-char pos)
    710             (if (funcall match-p (get-text-property (point) property))
    711                 (setq ended (funcall find-end (point)))
    712               ;; Skip past this section of non-matches.
    713               (setq pos (next-single-property-change (point) property))
    714               (unless pos
    715                 (goto-char origin)
    716                 (setq ended t)))))
    717         (and (not (eq ended t))
    718              ended))))))
    719 
    720 (compat-defun text-property-search-backward ;; <compat-tests:text-property-search-backward>
    721     (property &optional value predicate not-current)
    722   "Search for the previous region of text whose PROPERTY matches VALUE.
    723 
    724 Like `text-property-search-forward', which see, but searches backward,
    725 and if a matching region is found, place point at the start of the region."
    726   (let* ((match-p
    727           (lambda (prop-value)
    728             (funcall
    729              (cond
    730               ((eq predicate t)
    731                #'equal)
    732               ((eq predicate nil)
    733                (lambda (val p-val)
    734                  (not (equal val p-val))))
    735               (predicate))
    736              value prop-value)))
    737          (find-end
    738           (lambda (start)
    739             (let (end)
    740               (if (and value
    741                        (null predicate))
    742                   ;; This is the normal case: We're looking for areas where the
    743                   ;; values aren't, so we aren't interested in sub-areas where the
    744                   ;; property has different values, all non-matching value.
    745                   (let ((ended nil))
    746                     (while (not ended)
    747                       (setq end (previous-single-property-change (point) property))
    748                       (if (not end)
    749                           (progn
    750                             (goto-char (point-min))
    751                             (setq end (point)
    752                                   ended t))
    753                         (goto-char (1- end))
    754                         (unless (funcall match-p (get-text-property (point) property))
    755                           (goto-char end)
    756                           (setq ended t)))))
    757                 ;; End this at the first place the property changes value.
    758                 (setq end (previous-single-property-change
    759                            (point) property nil (point-min)))
    760                 (goto-char end))
    761               (make-prop-match
    762                :beginning end
    763                :end (1+ start)
    764                :value (get-text-property end property))))))
    765     (cond
    766      ;; We're at the start of the buffer; no previous matches.
    767      ((bobp)
    768       nil)
    769      ;; We're standing in the property we're looking for, so find the
    770      ;; end.
    771      ((funcall match-p (get-text-property (1- (point)) property))
    772       (let ((origin (point))
    773             (match (funcall find-end (1- (point)) property value predicate)))
    774         ;; When we want to ignore the current element, then repeat the
    775         ;; search if we haven't moved out of it yet.
    776         (if (and not-current
    777                  (equal (get-text-property (point) property)
    778                         (get-text-property origin property)))
    779             (text-property-search-backward property value predicate)
    780           match)))
    781      (t
    782       (let ((origin (point))
    783             (ended nil)
    784             pos)
    785         ;; Find the previous candidate.
    786         (while (not ended)
    787           (setq pos (previous-single-property-change (point) property))
    788           (if (not pos)
    789               (progn
    790                 (goto-char origin)
    791                 (setq ended t))
    792             (goto-char (1- pos))
    793             (if (funcall match-p (get-text-property (point) property))
    794                 (setq ended
    795                       (funcall find-end (point)))
    796               ;; Skip past this section of non-matches.
    797               (setq pos (previous-single-property-change (point) property))
    798               (unless pos
    799                 (goto-char origin)
    800                 (setq ended t)))))
    801         (and (not (eq ended t))
    802              ended))))))
    803 
    804 ;;;; Defined in ring.el
    805 
    806 (compat-defun ring-resize (ring size) ;; <compat-tests:ring-resize>
    807   "Set the size of RING to SIZE.
    808 If the new size is smaller, then the oldest items in the ring are
    809 discarded."
    810   :feature ring
    811   (when (integerp size)
    812     (let ((length (ring-length ring))
    813           (new-vec (make-vector size nil)))
    814       (if (= length 0)
    815           (setcdr ring (cons 0 new-vec))
    816         (let* ((hd (car ring))
    817                (old-size (ring-size ring))
    818                (old-vec (cddr ring))
    819                (copy-length (min size length))
    820                (copy-hd (mod (+ hd (- length copy-length)) length)))
    821           (setcdr ring (cons copy-length new-vec))
    822           ;; If the ring is wrapped, the existing elements must be written
    823           ;; out in the right order.
    824           (dotimes (j copy-length)
    825             (aset new-vec j (aref old-vec (mod (+ copy-hd j) old-size))))
    826           (setcar ring 0))))))
    827 
    828 ;;;; Defined in map-ynp.el
    829 
    830 (compat-version "26.2")
    831 
    832 (compat-defvar read-answer-short 'auto ;; <compat-tests:read-answer>
    833   "If non-nil, the `read-answer' function accepts single-character answers.
    834 If t, accept short (single key-press) answers to the question.
    835 If nil, require long answers.  If `auto', accept short answers if
    836 `use-short-answers' is non-nil, or the function cell of `yes-or-no-p'
    837 is set to `y-or-n-p'.
    838 
    839 Note that this variable does not affect calls to the more
    840 commonly-used `yes-or-no-p' function; it only affects calls to
    841 the `read-answer' function.  To control whether `yes-or-no-p'
    842 requires a long or a short answer, see the `use-short-answers'
    843 variable.")
    844 
    845 (compat-defun read-answer (question answers) ;; <compat-tests:read-answer>
    846   "Read an answer either as a complete word or its character abbreviation.
    847 Ask user a question and accept an answer from the list of possible answers.
    848 
    849 QUESTION should end in a space; this function adds a list of answers to it.
    850 
    851 ANSWERS is an alist with elements in the following format:
    852   (LONG-ANSWER SHORT-ANSWER HELP-MESSAGE)
    853 where
    854   LONG-ANSWER is a complete answer,
    855   SHORT-ANSWER is an abbreviated one-character answer,
    856   HELP-MESSAGE is a string describing the meaning of the answer.
    857 
    858 SHORT-ANSWER is not necessarily a single character answer.  It can be
    859 also a function key like F1, a character event such as C-M-h, or
    860 a control character like C-h.
    861 
    862 Example:
    863   \\='((\"yes\"  ?y \"perform the action\")
    864     (\"no\"   ?n \"skip to the next\")
    865     (\"all\"  ?! \"accept all remaining without more questions\")
    866     (\"help\" ?h \"show help\")
    867     (\"quit\" ?q \"exit\"))
    868 
    869 When `read-answer-short' is non-nil, accept short answers.
    870 
    871 Return a long answer even in case of accepting short ones.
    872 
    873 When `use-dialog-box' is t, pop up a dialog window to get user input."
    874   ;; NOTE: For simplicity we provide a primitive implementation based on
    875   ;; `read-multiple-choice', which does neither support long answers nor the the
    876   ;; gui dialog box.
    877   (cadr (read-multiple-choice
    878          (string-trim-right question)
    879          (delq nil
    880                (mapcar (lambda (x) (unless (equal "help" (car x))
    881                                      (list (cadr x) (car x) (caddr x))))
    882                        answers)))))
    883 
    884 (provide 'compat-27)
    885 ;;; compat-27.el ends here