Improve the optional translation of quotes

Fix several problems with the recently-added custom variable
help-quote-translation where the code would quote inconsistently
in help buffers.  Add support for quoting 'like this', which
is common in other GNU programs in ASCII environments.  Change
help-quote-translation to use more mnemonic values: values are now the
initial quoting char, e.g., (setq help-quote-translation ?`) gets the
traditional Emacs help-buffer quoting style `like this'.  Change the
default behavior of substitute-command-keys to match what's done in
set-locale-environment, i.e., quote ‘like this’ if displayable,
'like this' otherwise.
* doc/lispref/help.texi (Keys in Documentation): Document
new behavior of substitute-command-keys, and document
help-quote-translation.
* doc/lispref/tips.texi (Documentation Tips):
Mention the effect of help-quote-translation.
* etc/NEWS: Mention new behavior of substitute-command-keys,
and merge help-quote-translation news into it.
When talking about doc strings, mention new ways to type quotes.
* lisp/cedet/mode-local.el (overload-docstring-extension):
Revert my recent change to this function, which shouldn't be
needed as the result is a doc string.
* lisp/cedet/mode-local.el (mode-local-print-binding)
(mode-local-describe-bindings-2):
* lisp/cedet/srecode/srt-mode.el (srecode-macro-help):
* lisp/cus-theme.el (describe-theme-1):
* lisp/descr-text.el (describe-text-properties-1, describe-char):
* 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):
Use substitute-command-keys to ensure a more-consistent quoting
style in help buffers.
* lisp/cus-start.el (standard):
Document new help-quote-translation behavior.
* lisp/emacs-lisp/lisp-mode.el (lisp-fdefs):
* lisp/help-mode.el (help-xref-symbol-regexp, help-xref-info-regexp)
(help-xref-url-regexp):
* lisp/international/mule-cmds.el (help-xref-mule-regexp-template):
* lisp/wid-edit.el (widget-documentation-link-regexp):
Also match 'foo', in case we're in a help buffer generated when
help-quote-translation is ?'.
* src/doc.c: Include disptab.h, for DISP_CHAR_VECTOR.
(LEFT_SINGLE_QUOTATION_MARK, uLSQM0, uLSQM1, uLSQM2, uRSQM0)
(uRSQM1, uRSQM2, LSQM, RSQM): New constants.
(Fsubstitute_command_keys): Document and implement new behavior.
(Vhelp_quote_translation): Document new behavior.

1 files changed, 8 insertions, 5 deletions

diff --git a/lisp/faces.el b/lisp/faces.el
index 4366c0b9f23..ac6486ee46c 100644
--- a/lisp/faces.el
+++ b/lisp/faces.el
@@ -1428,10 +1428,12 @@ If FRAME is omitted or nil, use the selected frame."
 		  (when alias
 		    (setq face alias)
 		    (insert
-		     (format "\n  %s is an alias for the face ‘%s’.\n%s"
+		     (format (substitute-command-keys
+                              "\n  %s is an alias for the face ‘%s’.\n%s")
 			     f alias
 			     (if (setq obsolete (get f 'obsolete-face))
-				 (format "  This face is obsolete%s; use ‘%s’ instead.\n"
+				 (format (substitute-command-keys
+                                          "  This face is obsolete%s; use ‘%s’ instead.\n")
 					 (if (stringp obsolete)
 					     (format " since %s" obsolete)
 					   "")
@@ -1449,12 +1451,13 @@ If FRAME is omitted or nil, use the selected frame."
 		    (help-xref-button 1 'help-customize-face f)))
 		(setq file-name (find-lisp-object-file-name f 'defface))
 		(when file-name
-		  (princ "Defined in ‘")
+		  (princ (substitute-command-keys "Defined in ‘"))
 		  (princ (file-name-nondirectory file-name))
-		  (princ "’")
+		  (princ (substitute-command-keys "’"))
 		  ;; Make a hyperlink to the library.
 		  (save-excursion
-		    (re-search-backward "‘\\([^‘’]+\\)’" nil t)
+		    (re-search-backward
+                     (substitute-command-keys "‘\\([^‘’]+\\)’") nil t)
 		    (help-xref-button 1 'help-face-def f file-name))
 		  (princ ".")
 		  (terpri)