Support curved quotes in doc strings

Emacs's traditional doc string style has been to quote symbols
`like this'.  This worked well on now-obsolete terminals where
` and ' were symmetric quotes, but nowadays curved quotes
‘like this’ look better.  Support quoting the new way too.
(Bug#20385)
* doc/lispref/tips.texi (Documentation Tips): Symbols can be quoted
‘like-this’ as well as `like-this'.
* etc/NEWS: Mention this.
* lisp/cedet/mode-local.el (overload-docstring-extension)
(mode-local-print-binding, mode-local-describe-bindings-2):
* lisp/cus-theme.el (describe-theme-1):
* lisp/descr-text.el (describe-text-properties-1, describe-char):
* lisp/emacs-lisp/checkdoc.el (checkdoc-this-string-valid-engine):
* lisp/emacs-lisp/cl-generic.el (cl--generic-describe):
* lisp/emacs-lisp/eieio-opt.el (eieio-help-class)
(eieio-help-constructor):
* lisp/emacs-lisp/package.el (describe-package-1):
* lisp/faces.el (describe-face):
* lisp/help-fns.el (help-fns--key-bindings)
(help-fns--compiler-macro, help-fns--parent-mode, help-fns--obsolete):
(help-fns--interactive-only, describe-function-1):
(describe-variable):
* lisp/help.el (describe-mode):
* lisp/international/mule-cmds.el (describe-input-method)
(describe-language-environment):
* lisp/international/mule-diag.el (describe-character-set)
(print-coding-system-briefly, list-input-methods)
(list-input-methods-1):
Insert curved quotes rather than grave accent and apostrophe.
* lisp/cedet/srecode/texi.el (srecode-texi-texify-docstring):
* lisp/emacs-lisp/checkdoc.el (checkdoc-this-string-valid-engine)
(checkdoc-proper-noun-region-engine):
* lisp/emacs-lisp/lisp-mode.el (lisp-el-font-lock-keywords-2)
(lisp-cl-font-lock-keywords-2):
* lisp/finder.el (finder-font-lock-keywords):
* lisp/gnus/gnus-art.el (gnus-button-alist):
* lisp/help-fns.el (help-do-arg-highlight)
(describe-function-1, describe-variable):
* lisp/help-mode.el (help-xref-symbol-regexp)
(help-xref-info-regexp, help-xref-url-regexp):
* lisp/help.el (describe-mode):
* lisp/international/mule-cmds.el (help-xref-mule-regexp-template):
* lisp/wid-edit.el (widget-documentation-link-regexp):
Parse symbols quoted ‘like-this’ as well as `like-this'.
* lisp/progmodes/elisp-mode.el (emacs-lisp-mode):
Add "‘" and "’" to electric-pair-text-pairs.
(elisp--form-quoted-p): Also allow "‘" as a quoting char.
(elisp-completion-at-point, elisp--preceding-sexp):
Also treat "‘" and "’" as quoting chars.

1 files changed, 11 insertions, 9 deletions

diff --git a/lisp/emacs-lisp/checkdoc.el b/lisp/emacs-lisp/checkdoc.el
index 18361c8888f..4761ac5e6fc 100644
--- a/lisp/emacs-lisp/checkdoc.el
+++ b/lisp/emacs-lisp/checkdoc.el
@@ -1524,7 +1524,7 @@ may require more formatting")
      ;;     Instead, use the `\\[...]' construct to stand for them.
      (save-excursion
        (let ((f nil) (m nil) (start (point))
-	     (re "[^`A-Za-z0-9_]\\([CMA]-[a-zA-Z]\\|\\(\\([CMA]-\\)?\
+	     (re "[^`‘A-Za-z0-9_]\\([CMA]-[a-zA-Z]\\|\\(\\([CMA]-\\)?\
 mouse-[0-3]\\)\\)\\>"))
 	 ;; Find the first key sequence not in a sample
 	 (while (and (not f) (setq m (re-search-forward re e t)))
@@ -1554,7 +1554,8 @@ mouse-[0-3]\\)\\)\\>"))
      (save-excursion
        (let ((case-fold-search t)
 	     (ret nil) mb me)
-	 (while (and (re-search-forward "`\\(\\sw\\(\\sw\\|\\s_\\)+\\)'" e t)
+	 (while (and (re-search-forward
+                      "[`‘]\\(\\sw\\(\\sw\\|\\s_\\)+\\)['’]" e t)
 		     (not ret))
 	   (let* ((ms1 (match-string 1))
 		  (sym (intern-soft ms1)))
@@ -1785,16 +1786,17 @@ Replace with \"%s\"? " original replace)
 	     )))
      ;;* When a documentation string refers to a Lisp symbol, write it as
      ;;  it would be printed (which usually means in lower case), with
-     ;;  single-quotes around it.  For example: `lambda'.  There are two
-     ;;  exceptions: write t and nil without single-quotes.  (In this
-     ;;  manual, we normally do use single-quotes for those symbols.)
+     ;;  single-quotes around it.  For example: ‘lambda’.  There are two
+     ;;  exceptions: write t and nil without single-quotes.  (For
+     ;;  compatibility with an older Emacs style, quoting with ` and '
+     ;;  also works, e.g., `lambda' is treated like ‘lambda’.)
      (save-excursion
        (let ((found nil) (start (point)) (msg nil) (ms nil))
 	 (while (and (not msg)
 		     (re-search-forward
 		      ;; Ignore manual page references like
 		      ;; git-config(1).
-		      "[^-([`':a-zA-Z]\\(\\w+[:-]\\(\\w\\|\\s_\\)+\\)[^](']"
+		      "[^-([`'‘’:a-zA-Z]\\(\\w+[:-]\\(\\w\\|\\s_\\)+\\)[^]('’]"
 		      e t))
 	   (setq ms (match-string 1))
 	   ;; A . is a \s_ char, so we must remove periods from
@@ -1812,7 +1814,7 @@ Replace with \"%s\"? " original replace)
 		 (if (checkdoc-autofix-ask-replace
 		      (match-beginning 1) (+ (match-beginning 1)
 					     (length ms))
-		      msg (concat "`" ms "'") t)
+		      msg (concat "‘" ms "’") t)
 		     (setq msg nil)
 		   (setq msg
 			 (format "Lisp symbol `%s' should appear in quotes"
@@ -1824,7 +1826,7 @@ Replace with \"%s\"? " original replace)
 	   nil)))
      ;; t and nil case
      (save-excursion
-       (if (re-search-forward "\\(`\\(t\\|nil\\)'\\)" e t)
+       (if (re-search-forward "\\([`‘]\\(t\\|nil\\)['’]\\)" e t)
 	   (if (checkdoc-autofix-ask-replace
 		(match-beginning 1) (match-end 1)
 		(format "%s should not appear in quotes.  Remove? "
@@ -1989,7 +1991,7 @@ If the offending word is in a piece of quoted text, then it is skipped."
             (if (and (not (save-excursion
                             (goto-char b)
                             (forward-char -1)
-                            (looking-at "`\\|\"\\|\\.\\|\\\\")))
+                            (looking-at "[`\".‘]\\|\\\\")))
                      ;; surrounded by /, as in a URL or filename: /emacs/
                      (not (and (= ?/ (char-after e))
                                (= ?/ (char-before b))))