Revert "Extend ‘format’ to translate curved quotes"

This reverts commit 244c801689d2f7a80480d83cd7d092d4762ebe08.

7 files changed, 120 insertions, 187 deletions

diff --git a/doc/lispref/help.texi b/doc/lispref/help.texi
index ab1696e6712..ca8ae3f314a 100644
--- a/doc/lispref/help.texi
+++ b/doc/lispref/help.texi
@@ -347,11 +347,19 @@ and @samp{\=\=} puts @samp{\=} into the output.
 @strong{Please note:} Each @samp{\} must be doubled when written in a
 string in Emacs Lisp.
 
+@defvar text-quoting-style
 @cindex curved quotes
 @cindex curly quotes
-The value of the @code{text-quoting-style} variable specifies the style
+The value of this variable specifies the style
 @code{substitute-command-keys} uses when generating left and right
-quotes.  @xref{Formatting Strings}, for more information.
+quotes.  If the variable's value is @code{curve}, the style is
+@t{‘like this’} with curved single quotes.  If the value is
+@code{straight}, the style is @t{'like this'} with straight
+apostrophes.  If the value is @code{grave}, the style is @t{`like
+this'} with grave accent and apostrophe.  The default value @code{nil}
+acts like @code{curve} if curved single quotes are displayable, and
+like @code{grave} otherwise.
+@end defvar
 
 @defun substitute-command-keys string
 This function scans @var{string} for the above special sequences and
diff --git a/doc/lispref/strings.texi b/doc/lispref/strings.texi
index 8de1473b83d..580eb43acca 100644
--- a/doc/lispref/strings.texi
+++ b/doc/lispref/strings.texi
@@ -805,27 +805,22 @@ formatting feature described here; they differ from @code{format} only
 in how they use the result of formatting.
 
 @defun format string &rest objects
-This function returns a string that is equivalent to copying
+This function returns a new string that is made by copying
 @var{string} and then replacing any format specification
 in the copy with encodings of the corresponding @var{objects}.  The
 arguments @var{objects} are the computed values to be formatted.
 
 The characters in @var{string}, other than the format specifications,
 are copied directly into the output, including their text properties,
-if any.  If the output equals @var{string}, this function may return
-@var{string} itself rather than a new copy.
+if any.
 @end defun
 
 @cindex @samp{%} in format
 @cindex format specification
-@cindex curved quotes
-@cindex curly quotes
   A format specification is a sequence of characters beginning with a
-@samp{%} or is a curved single quotation mark.  Except for @samp{%%}
-and quotation marks, each format specification says how to represent
-one of the arguments @var{objects}.  For example, if there
-is a @samp{%d} in @var{string}, the @code{format} function replaces it
-with the decimal representation of the integer to be formatted.
+@samp{%}.  Thus, if there is a @samp{%d} in @var{string}, the
+@code{format} function replaces it with the printed representation of
+one of the values to be formatted (one of the arguments @var{objects}).
 For example:
 
 @example
@@ -835,12 +830,11 @@ For example:
 @end group
 @end example
 
-  Since @code{format} interprets @samp{%}, @samp{‘} and @samp{’}
-characters as format
+  Since @code{format} interprets @samp{%} characters as format
 specifications, you should @emph{never} pass an arbitrary string as
 the first argument.  This is particularly true when the string is
 generated by some Lisp code.  Unless the string is @emph{known} to
-never include any of the three special characters, pass @code{"%s"}, described
+never include any @samp{%} characters, pass @code{"%s"}, described
 below, as the first argument, and the string as the second, like this:
 
 @example
@@ -914,27 +908,17 @@ is shorter.
 Replace the specification with a single @samp{%}.  This format
 specification is unusual in that it does not use a value.  For example,
 @code{(format "%% %d" 30)} returns @code{"% 30"}.
-
-@item ‘
-@itemx ’
-@cindex curved quotes
-@cindex curly quotes
-Replace the specification with a left or right quote, respectively.
-Although typically a curved single quotation mark stands for itself,
-other quoting styles are available as per the variable
-@samp{text-quoting-style} described below.
 @end table
 
-  Any other format character after @samp{%} results in an @samp{Invalid format
+  Any other format character results in an @samp{Invalid format
 operation} error.
 
-  Here are several examples, which assume the typical quoting style
-where curved single quotes stand for themselves:
+  Here are several examples:
 
 @example
 @group
-(format "The name of this buffer is ‘%s’." (buffer-name))
-     @result{} "The name of this buffer is ‘strings.texi’."
+(format "The name of this buffer is %s." (buffer-name))
+     @result{} "The name of this buffer is strings.texi."
 
 (format "The buffer object prints as %qs." (current-buffer))
      @result{} "The buffer object prints as ‘strings.texi’."
@@ -948,7 +932,7 @@ where curved single quotes stand for themselves:
 
 @cindex field width
 @cindex padding
-  A @samp{%} specification can have a @dfn{width}, which is a decimal number
+  A specification can have a @dfn{width}, which is a decimal number
 between the @samp{%} and the specification character.  If the printed
 representation of the object contains fewer characters than this
 width, @code{format} extends it with padding.  The width specifier is
@@ -964,7 +948,7 @@ the width specifier normally consists of spaces inserted on the left:
 If the width is too small, @code{format} does not truncate the
 object's printed representation.  Thus, you can use a width to specify
 a minimum spacing between columns with no risk of losing information.
-In the following two examples, @samp{%7s} specifies a minimum width
+In the following three examples, @samp{%7s} specifies a minimum width
 of 7.  In the first case, the string inserted in place of @samp{%7s}
 has only 3 letters, and needs 4 blank spaces as padding.  In the
 second case, the string @code{"specification"} is 13 letters wide but
@@ -972,12 +956,12 @@ is not truncated.
 
 @example
 @group
-(format "The word ‘%7s’ has %d letters in it."
+(format "The word '%7s' has %d letters in it."
         "foo" (length "foo"))
-     @result{} "The word ‘    foo’ has 3 letters in it."
-(format "The word ‘%7s’ has %d letters in it."
+     @result{} "The word '    foo' has 3 letters in it."
+(format "The word '%7s' has %d letters in it."
         "specification" (length "specification"))
-     @result{} "The word ‘specification’ has 13 letters in it."
+     @result{} "The word 'specification' has 13 letters in it."
 @end group
 @end example
 
@@ -1022,14 +1006,14 @@ variable @samp{text-quoting-style} described below.
 (format "%q-6d is padded on the right" 123)
      @result{} "‘123   ’ is padded on the right"
 
-(format "The word ‘%-7s’ actually has %d letters in it."
+(format "The word '%-7s' actually has %d letters in it."
         "foo" (length "foo"))
-     @result{} "The word ‘foo    ’ actually has 3 letters in it."
+     @result{} "The word 'foo    ' actually has 3 letters in it."
 @end group
 @end example
 
 @cindex precision in format specifications
-  The @samp{%} specification characters allow an optional @dfn{precision}
+  All the specification characters allow an optional @dfn{precision}
 before the character (after the width, if present).  The precision is
 a decimal-point @samp{.} followed by a digit-string.  For the
 floating-point specifications (@samp{%e}, @samp{%f}, @samp{%g}), the
@@ -1040,19 +1024,6 @@ shows only the first three characters of the representation for
 @var{object}.  Precision has no effect for other specification
 characters.
 
-@defvar text-quoting-style
-@cindex curved quotes
-@cindex curly quotes
-This variable specifies the style @code{format} uses when generating
-left and right quotes.  If the value is @code{curve}, the style is
-@t{‘like this’} with curved single quotes.  If the value is
-@code{straight}, the style is @t{'like this'} with straight
-apostrophes.  If the value is @code{grave}, the style is @t{`like
-this'} with grave accent and apostrophe.  The default value @code{nil}
-acts like @code{curve} if curved single quotes are displayable, and
-like @code{grave} otherwise.
-@end defvar
-
 @node Case Conversion
 @section Case Conversion in Lisp
 @cindex upper case
diff --git a/etc/NEWS b/etc/NEWS
index 72af95e8de5..d3a01c20247 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -910,19 +910,6 @@ denied" instead of "permission denied".  The old behavior was problematic
 in languages like German where downcasing rules depend on grammar.
 
 +++
-** ‘format’ now replaces curved single quotes.
-That is, it replaces strings' curved single quotes (also known as
-curly quotes) as per the value of the new custom variable
-‘text-quoting-style’: ‘curve’ means replace curved quotes with
-themselves ‘like this’, ‘straight’ means use straight apostrophes
-'like this', ‘grave’ means use grave accent and apostrophe `like
-this', and nil (default) means use curved quotes if displayable and
-grave accent and apostrophe otherwise.  Because it now may be used
-in many contexts where it's a no-op, ‘format’ is no longer required to
-create a string, and may return its first argument if the argument
-already has the correct value.
-
-+++
 ** New ‘format’ flag ‘q’
 The new ‘q’ flag causes ‘format’ to quote the output representation as
 per the value of ‘text quoting-style’.  E.g., (format "%qs failed"
diff --git a/lisp/calc/calc-help.el b/lisp/calc/calc-help.el
index 01ab49510cd..50a0291e4cd 100644
--- a/lisp/calc/calc-help.el
+++ b/lisp/calc/calc-help.el
@@ -365,7 +365,7 @@ C-w  Describe how there is no warranty for Calc."
     (let (Info-history)
       (Info-goto-node (buffer-substring (match-beginning 1) (match-end 1))))
     (let* ((string-target (or target thing))
-           (quoted (concat "['`‘]" (regexp-quote string-target) "['’]"))
+           (quoted (format "['`‘]%s['’]" (regexp-quote string-target)))
            (bracketed (format "\\[%s\\]\\|(%s)\\|\\<The[ \n]%s"
                               quoted quoted quoted)))
       (or (let ((case-fold-search nil))
diff --git a/lisp/emacs-lisp/derived.el b/lisp/emacs-lisp/derived.el
index 1f8572b278b..ee137f1771e 100644
--- a/lisp/emacs-lisp/derived.el
+++ b/lisp/emacs-lisp/derived.el
@@ -331,10 +331,9 @@ which more-or-less shadow%s %s's corresponding table%s."
                         "\n\nThis mode "
                       (concat
                        "\n\nIn addition to any hooks its parent mode "
-                       (if (string-match (concat "[`%‘]"
+                       (if (string-match (format "[`‘]%s['’]"
                                                  (regexp-quote
-                                                  (symbol-name parent))
-                                                 "['%’]")
+                                                  (symbol-name parent)))
                                          docstring)
                            nil
                          (format "`%s' " parent))
diff --git a/lisp/info.el b/lisp/info.el
index 8a43a8182aa..454fadaca03 100644
--- a/lisp/info.el
+++ b/lisp/info.el
@@ -3398,12 +3398,10 @@ Give an empty topic name to go to the Index node itself."
             (re-search-forward (format
                                 "[a-zA-Z]+: [a-zA-Z0-9_ *&]+ %s\\( \\|$\\)"
                                 (regexp-quote name)) nil t)
-            (search-forward (concat "['`‘]" name "['’]") nil t)
+            (search-forward (format "['`‘]%s['’]" name) nil t)
             (and (string-match "\\`.*\\( (.*)\\)\\'" name)
                  (search-forward
-                  (concat "['`%‘]"
-                          (substring name 0 (match-beginning 1))
-                          "['%’]")
+                  (format "['`‘]%s['’]" (substring name 0 (match-beginning 1)))
                   nil t))
             (search-forward name nil t)
             ;; Try again without the " <1>" makeinfo can append
diff --git a/src/editfns.c b/src/editfns.c
index 0e1b0c8f01d..8ac0ef16999 100644
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -3800,9 +3800,8 @@ DEFUN ("format", Fformat, Sformat, 1, MANY, 0,
 The first argument is a format control string.
 The other arguments are substituted into it to make the result, a string.
 
-The format control string may contain ordinary characters,
-%-sequences meaning to substitute the next available argument,
-and curved single quotation marks meaning to substitute quotes.
+The format control string may contain %-sequences meaning to substitute
+the next available argument:
 
 %s means print a string argument.  Actually, prints any object, with `princ'.
 %d means print as number in decimal (%o octal, %x hex).
@@ -3850,12 +3849,6 @@ precision specifier says how many decimal places to show; if zero, the
 decimal point itself is omitted.  For %s and %S, the precision
 specifier truncates the string to the given width.
 
-\\=‘ and \\=’ means print left and right quotes as per
-‘text-quoting-style’.
-
-Return the first argument if it contains no format directives.
-Otherwise, return a new string.
-
 usage: (format STRING &rest OBJECTS)  */)
   (ptrdiff_t nargs, Lisp_Object *args)
 {
@@ -3868,7 +3861,6 @@ usage: (format STRING &rest OBJECTS)  */)
   ptrdiff_t buf_save_value_index IF_LINT (= 0);
   char *format, *end, *format_start;
   ptrdiff_t formatlen, nchars;
-  bool changed = false;
   /* True if the format is multibyte.  */
   bool multibyte_format = 0;
   /* True if the output should be a multibyte string,
@@ -4020,7 +4012,6 @@ usage: (format STRING &rest OBJECTS)  */)
           if (format == end)
             error ("Format string ends in middle of format specifier");
 
-          changed = true;
           memset (&discarded[format0 - format_start], 1, format - format0);
           conversion = *format;
           if (conversion == '%')
@@ -4493,20 +4484,6 @@ usage: (format STRING &rest OBJECTS)  */)
 
               convbytes = format - src;
               memset (&discarded[src + 1 - format_start], 2, convbytes - 1);
-
-              if (quoting_style != CURVE_QUOTING_STYLE && convbytes == 3
-                  && (unsigned char) src[0] == uLSQM0
-                  && (unsigned char) src[1] == uLSQM1
-                  && ((unsigned char) src[2] == uLSQM2
-                      || (unsigned char) src[2] == uRSQM2))
-                {
-                  convbytes = 1;
-                  str[0] = (((unsigned char) src[2] == uLSQM2
-                             && quoting_style == GRAVE_QUOTING_STYLE)
-                            ? '`' : '\'');
-                  src = (char *) str;
-                  changed = true;
-                }
             }
           else
             {
@@ -4518,7 +4495,6 @@ usage: (format STRING &rest OBJECTS)  */)
                   int c = BYTE8_TO_CHAR (uc);
                   convbytes = CHAR_STRING (c, str);
                   src = (char *) str;
-                  changed = true;
                 }
             }
 
@@ -4566,119 +4542,113 @@ usage: (format STRING &rest OBJECTS)  */)
   if (bufsize < p - buf)
     emacs_abort ();
 
-  if (!changed)
-    val = args[0];
-  else
-    {
-      if (maybe_combine_byte)
-        nchars = multibyte_chars_in_text ((unsigned char *) buf, p - buf);
-      val = make_specified_string (buf, nchars, p - buf, multibyte);
+  if (maybe_combine_byte)
+    nchars = multibyte_chars_in_text ((unsigned char *) buf, p - buf);
+  val = make_specified_string (buf, nchars, p - buf, multibyte);
 
-      /* If the format string has text properties, or any of the string
-         arguments has text properties, set up text properties of the
-         result string.  */
+  /* If the format string has text properties, or any of the string
+     arguments has text properties, set up text properties of the
+     result string.  */
 
-      if (string_intervals (args[0]) || arg_intervals)
-        {
-          Lisp_Object len, new_len, props;
-          struct gcpro gcpro1;
+  if (string_intervals (args[0]) || arg_intervals)
+    {
+      Lisp_Object len, new_len, props;
+      struct gcpro gcpro1;
 
-          /* Add text properties from the format string.  */
-          len = make_number (SCHARS (args[0]));
-          props = text_property_list (args[0], make_number (0), len, Qnil);
-          GCPRO1 (props);
+      /* Add text properties from the format string.  */
+      len = make_number (SCHARS (args[0]));
+      props = text_property_list (args[0], make_number (0), len, Qnil);
+      GCPRO1 (props);
 
-          if (CONSP (props))
+      if (CONSP (props))
+        {
+          ptrdiff_t bytepos = 0, position = 0, translated = 0;
+          ptrdiff_t argn = 1;
+          Lisp_Object list;
+
+          /* Adjust the bounds of each text property
+             to the proper start and end in the output string.  */
+
+          /* Put the positions in PROPS in increasing order, so that
+             we can do (effectively) one scan through the position
+             space of the format string.  */
+          props = Fnreverse (props);
+
+          /* BYTEPOS is the byte position in the format string,
+             POSITION is the untranslated char position in it,
+             TRANSLATED is the translated char position in BUF,
+             and ARGN is the number of the next arg we will come to.  */
+          for (list = props; CONSP (list); list = XCDR (list))
             {
-              ptrdiff_t bytepos = 0, position = 0, translated = 0;
-              ptrdiff_t argn = 1;
-              Lisp_Object list;
-
-              /* Adjust the bounds of each text property
-                 to the proper start and end in the output string.  */
-
-              /* Put the positions in PROPS in increasing order, so that
-                 we can do (effectively) one scan through the position
-                 space of the format string.  */
-              props = Fnreverse (props);
-
-              /* BYTEPOS is the byte position in the format string,
-                 POSITION is the untranslated char position in it,
-                 TRANSLATED is the translated char position in BUF,
-                 and ARGN is the number of the next arg we will come to.  */
-              for (list = props; CONSP (list); list = XCDR (list))
-                {
-                  Lisp_Object item;
-                  ptrdiff_t pos;
+              Lisp_Object item;
+              ptrdiff_t pos;
 
-                  item = XCAR (list);
+              item = XCAR (list);
 
-                  /* First adjust the property start position.  */
-                  pos = XINT (XCAR (item));
+              /* First adjust the property start position.  */
+              pos = XINT (XCAR (item));
 
-                  /* Advance BYTEPOS, POSITION, TRANSLATED and ARGN
-                     up to this position.  */
-                  for (; position < pos; bytepos++)
+              /* Advance BYTEPOS, POSITION, TRANSLATED and ARGN
+                 up to this position.  */
+              for (; position < pos; bytepos++)
+                {
+                  if (! discarded[bytepos])
+                    position++, translated++;
+                  else if (discarded[bytepos] == 1)
                     {
-                      if (! discarded[bytepos])
-                        position++, translated++;
-                      else if (discarded[bytepos] == 1)
+                      position++;
+                      if (translated == info[argn].start)
                         {
-                          position++;
-                          if (translated == info[argn].start)
-                            {
-                              translated += info[argn].end - info[argn].start;
-                              argn++;
-                            }
+                          translated += info[argn].end - info[argn].start;
+                          argn++;
                         }
                     }
+                }
 
-                  XSETCAR (item, make_number (translated));
+              XSETCAR (item, make_number (translated));
 
-                  /* Likewise adjust the property end position.  */
-                  pos = XINT (XCAR (XCDR (item)));
+              /* Likewise adjust the property end position.  */
+              pos = XINT (XCAR (XCDR (item)));
 
-                  for (; position < pos; bytepos++)
+              for (; position < pos; bytepos++)
+                {
+                  if (! discarded[bytepos])
+                    position++, translated++;
+                  else if (discarded[bytepos] == 1)
                     {
-                      if (! discarded[bytepos])
-                        position++, translated++;
-                      else if (discarded[bytepos] == 1)
+                      position++;
+                      if (translated == info[argn].start)
                         {
-                          position++;
-                          if (translated == info[argn].start)
-                            {
-                              translated += info[argn].end - info[argn].start;
-                              argn++;
-                            }
+                          translated += info[argn].end - info[argn].start;
+                          argn++;
                         }
                     }
-
-                  XSETCAR (XCDR (item), make_number (translated));
                 }
 
-              add_text_properties_from_list (val, props, make_number (0));
+              XSETCAR (XCDR (item), make_number (translated));
             }
 
-          /* Add text properties from arguments.  */
-          if (arg_intervals)
-            for (n = 1; n < nargs; ++n)
-              if (info[n].intervals)
-                {
-                  len = make_number (SCHARS (args[n]));
-                  new_len = make_number (info[n].end - info[n].start);
-                  props = text_property_list (args[n], make_number (0),
-                                              len, Qnil);
-                  props = extend_property_ranges (props, new_len);
-                  /* If successive arguments have properties, be sure that
-                     the value of `composition' property be the copy.  */
-                  if (n > 1 && info[n - 1].end)
-                    make_composition_value_copy (props);
-                  add_text_properties_from_list (val, props,
-                                                 make_number (info[n].start));
-                }
-
-          UNGCPRO;
+          add_text_properties_from_list (val, props, make_number (0));
         }
+
+      /* Add text properties from arguments.  */
+      if (arg_intervals)
+        for (n = 1; n < nargs; ++n)
+          if (info[n].intervals)
+            {
+              len = make_number (SCHARS (args[n]));
+              new_len = make_number (info[n].end - info[n].start);
+              props = text_property_list (args[n], make_number (0), len, Qnil);
+              props = extend_property_ranges (props, new_len);
+              /* If successive arguments have properties, be sure that
+                 the value of `composition' property be the copy.  */
+              if (n > 1 && info[n - 1].end)
+                make_composition_value_copy (props);
+              add_text_properties_from_list (val, props,
+                                             make_number (info[n].start));
+            }
+
+      UNGCPRO;
     }
 
   /* If we allocated BUF or INFO with malloc, free it too.  */