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Diffstat (limited to 'lisp/textmodes/emacs-news-mode.el')
| -rw-r--r-- | lisp/textmodes/emacs-news-mode.el | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/lisp/textmodes/emacs-news-mode.el b/lisp/textmodes/emacs-news-mode.el new file mode 100644 index 00000000000..fdb3cb86284 --- /dev/null +++ b/lisp/textmodes/emacs-news-mode.el @@ -0,0 +1,224 @@ +;;; emacs-news-mode.el --- major mode to edit and view the NEWS file -*- lexical-binding: t; -*- + +;; Copyright (C) 2022 Free Software Foundation, Inc. + +;; Keywords: tools + +;; 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/>. + +;;; Commentary: + +;;; Code: + +(eval-when-compile (require 'cl-lib)) + +(defgroup emacs-news-mode nil + "Major mode for editing and viewing the Emacs NEWS file." + :group 'lisp) + +(defface emacs-news-is-documented + '((t :inherit font-lock-type-face)) + "Face used for displaying the \"is documented\" tag." + :version "29.1") + +(defface emacs-news-does-not-need-documentation + '((t :inherit font-lock-preprocessor-face)) + "Face used for displaying the \"does not need documentation\" tag." + :version "29.1") + +(defvar-keymap emacs-news-mode-map + "C-c C-s" #'emacs-news-next-untagged-entry + "C-c C-r" #'emacs-news-previous-untagged-entry + "C-c C-g" #'emacs-news-goto-section + "C-c C-f" #'emacs-news-find-heading + "C-c C-n" #'emacs-news-count-untagged-entries) + +(defvar emacs-news-mode-font-lock-keywords + `(("^---$" 0 'emacs-news-does-not-need-documentation) + ("^\\+\\+\\+$" 0 'emacs-news-is-documented))) + +(defun emacs-news--mode-common () + (setq-local font-lock-defaults '(emacs-news-mode-font-lock-keywords t)) + (setq-local outline-regexp "\\*+ " + outline-minor-mode-cycle t + ;; We subtract one from the level, because we have a + ;; space after the asterisks. + outline-level (lambda () (1- (length (match-string 0)))) + outline-minor-mode-highlight 'append) + (outline-minor-mode)) + +;;;###autoload +(define-derived-mode emacs-news-mode text-mode "NEWS" + "Major mode for editing the Emacs NEWS file." + (setq-local fill-paragraph-function #'emacs-news--fill-paragraph) + (emacs-news--mode-common)) + +;;;###autoload +(define-derived-mode emacs-news-view-mode special-mode "NEWS" + "Major mode for viewing the Emacs NEWS file." + (setq buffer-read-only t) + (emacs-news--buttonize) + (button-mode) + (emacs-news--mode-common)) + +(defun emacs-news--fill-paragraph (&optional justify) + (cond + ;; We're in a heading -- do nothing. + ((save-excursion + (beginning-of-line) + (looking-at "\\*+ ")) + ) + ;; We're in a news item -- exclude the heading before filling. + ((and (save-excursion + (re-search-backward (concat "^\\(?:" paragraph-start "\\|\\*+ \\)") + nil t)) + (= (char-after (match-beginning 0)) ?*)) + (save-restriction + (narrow-to-region (save-excursion + (goto-char (match-beginning 0)) + (forward-line 1) + (point)) + (point-max)) + (fill-paragraph justify))) + ;; Fill normally. + (t + (fill-paragraph justify)))) + +(defun emacs-news-next-untagged-entry (&optional reverse) + "Go to the next untagged NEWS entry. +If REVERSE (interactively, the prefix), go to the previous +untagged NEWS entry." + (interactive "P" emacs-news-mode) + (let ((start (point)) + (found nil)) + ;; Don't consider the current line, because that would stop + ;; progress if calling this command repeatedly. + (unless reverse + (forward-line 1)) + (while (and (not found) + (funcall (if reverse #'re-search-backward + #'re-search-forward) + "^\\(\\*+\\) " nil t)) + (when (and (not (save-excursion + (forward-line -1) + (looking-at "---$\\|\\+\\+\\+$"))) + ;; We have an entry without a tag before it, but + ;; check whether it's a heading (which we can + ;; determine if the next entry has more asterisks). + (not (emacs-news--heading-p))) + ;; It wasn't a sub-heading, so we've found one. + (setq found t))) + (if found + (progn + (push-mark start) + (message "Untagged entry") + (beginning-of-line) + t) + (message "No further untagged entries") + (goto-char start) + nil))) + +(defun emacs-news--heading-p () + (save-excursion + (beginning-of-line) + ;; A heading starts with * characters, and then a blank line, and + ;; then paragraphs with more * characters than in the heading. + (and (looking-at "\\(\\*+\\) ") + (let ((level (length (match-string 1)))) + (forward-line 1) + (and (looking-at "$") + (re-search-forward "^\\(\\*+\\) " nil t) + (> (length (match-string 1)) level)))))) + +(defun emacs-news-previous-untagged-entry () + "Go to the previous untagged NEWS entry." + (interactive nil emacs-news-mode) + (emacs-news-next-untagged-entry t)) + +(defun emacs-news-count-untagged-entries () + "Say how many untagged entries there are in the current NEWS buffer." + (interactive nil emacs-news-mode) + (save-excursion + (goto-char (point-min)) + (let ((i 0)) + (while (emacs-news-next-untagged-entry) + (setq i (1+ i))) + (message (if (= i 1) + "There's 1 untagged entry" + (format "There are %s untagged entries" i)))))) + +(defun emacs-news--buttonize () + "Make manual and symbol references into buttons." + (save-excursion + (with-silent-modifications + (let ((inhibit-read-only t)) + ;; Do functions and variables. + (goto-char (point-min)) + (search-forward "\f" nil t) + (while (re-search-forward "'\\([^-][^ \t\n]+\\)'" nil t) + ;; Filter out references to key sequences. + (let ((string (match-string 1))) + (when-let ((symbol (intern-soft string))) + (when (or (boundp symbol) + (fboundp symbol)) + (buttonize-region (match-beginning 1) (match-end 1) + (lambda (symbol) + (describe-symbol symbol)) + symbol))))) + ;; Do manual references. + (goto-char (point-min)) + (search-forward "\f" nil t) + (while (re-search-forward "\"\\(([a-z0-9]+)[ \n][^\"]\\{1,80\\}\\)\"" + nil t) + (buttonize-region (match-beginning 1) (match-end 1) + (lambda (node) (info node)) + (match-string 1))))))) + +(defun emacs-news--sections (regexp) + (let ((sections nil)) + (save-excursion + (goto-char (point-min)) + (while (re-search-forward (concat "^" regexp "\\(.*\\)") nil t) + (when (save-match-data (emacs-news--heading-p)) + (push (buffer-substring-no-properties + (match-beginning 1) (match-end 1)) + sections)))) + (nreverse sections))) + +(defun emacs-news-goto-section (section) + "Go to SECTION in the Emacs NEWS file." + (interactive (list + (completing-read "Goto section: " (emacs-news--sections "\\* ") + nil t)) + emacs-news-mode) + (goto-char (point-min)) + (when (search-forward (concat "\n* " section) nil t) + (beginning-of-line))) + +(defun emacs-news-find-heading (heading) + "Go to HEADING in the Emacs NEWS file." + (interactive (list + (completing-read "Goto heading: " + (emacs-news--sections "\\*\\*\\*? ") + nil t)) + emacs-news-mode) + (goto-char (point-min)) + (when (re-search-forward (concat "^*+ " (regexp-quote heading)) nil t) + (beginning-of-line))) + +(provide 'emacs-news-mode) + +;;; emacs-news-mode.el ends here |