Merge from origin/emacs-26

af1624f * lisp/net/shr.el (shr-browse-url): Doc fix.  (Bug#30957)
3a451bd ; * doc/emacs/msdos.texi: Fix wording of last change.
3bc1e2f Mention `key-description' as inverse of `kbd' (Bug#30942)
e50196e Document return value of pcase (Bug#30425)
8a2466f * doc/emacs/macos.texi: Tweak grammar and capitalization.
9db62bf Distinguish free from non-free OSes
ff49d86 * doc/emacs/misc.texi (Amusements): Avoid non-printing charac...
5bab671 Fix xrefs in pdf Emacs manual

doc/emacs/fortran-xtra.texi

@@ -208,7 +208,13 @@ line is a continuation of the previous line.  We call this @dfn{fixed
 form}.  (In GNU Emacs we always count columns from 0; but note that
 the Fortran standard counts from 1.  You can customize the variable
 @code{column-number-indicator-zero-based} to make the column display
-Fortran-like; @pxref{Optional Mode Line}.)  The variable
+@iftex
+Fortran-like; @pxref{Optional Mode Line,,, emacs, the Emacs Manual}.)
+@end iftex
+@ifnottex
+Fortran-like; @pxref{Optional Mode Line}.)
+@end ifnottex
+The variable
 @code{fortran-continuation-string} specifies what character to put in
 column 5.  A line that starts with a tab character followed by any digit
 except @samp{0} is also a continuation line.  We call this style of
@@ -254,7 +260,13 @@ column 8 must consist of one tab character.
 indentation assumes it is a line number and moves it to columns 0
 through 4.  (Columns always count from 0 in Emacs, but setting
 @code{column-number-indicator-zero-based} to @code{nil} can change
-that, @pxref{Optional Mode Line}.)
+that,
+@iftex
+@pxref{Optional Mode Line,,, emacs, the Emacs Manual}.)
+@end iftex
+@ifnottex
+@pxref{Optional Mode Line}.)
+@end ifnottex
 
 @vindex fortran-line-number-indent
   Line numbers of four digits or less are normally indented one space.
@@ -535,7 +547,13 @@ statement body.  Column numbers appear above them.
 
   Note that the column numbers count from zero, as always in GNU Emacs
 (but customizing @code{column-number-indicator-zero-based} can change
-column display to match that of Fortran; @pxref{Optional Mode Line}).
+column display to match that of Fortran;
+@iftex
+@pxref{Optional Mode Line,,, emacs, the Emacs Manual}.)
+@end iftex
+@ifnottex
+@pxref{Optional Mode Line}.)
+@end ifnottex
 As a result, the numbers may be one less than those you are familiar
 with; but the positions they indicate in the line are standard for
 Fortran.

doc/emacs/macos.texi

@@ -14,6 +14,14 @@ built either without window system support, with X11, or with the
 Cocoa interface; this section only applies to the Cocoa build.  This
 does not support versions before macOS 10.6.
 
+  GNUstep is free software; macOS is not.  Because it is a non-free
+operating system, macOS denies its users the freedom that every computer
+user deserves.  That is an injustice.  For your freedom's sake, we
+urge you to switch to a free operating system.
+
+  We support GNU Emacs on proprietary operating systems because
+we hope this taste of freedom will inspire users to escape from them.
+
   For various historical and technical reasons, Emacs uses the term
 @samp{Nextstep} internally, instead of ``Cocoa'' or ``macOS''; for
 instance, most of the commands and variables described in this section

doc/emacs/misc.texi

@@ -3011,7 +3011,7 @@ is idle.
 
 @findex butterfly
 @cindex butterfly
-  Real Programmers™ deploy @kbd{M-x butterfly}, which uses butterflies
+  ``Real Programmers'' deploy @kbd{M-x butterfly}, which uses butterflies
 to flip a bit on the drive platter, see @uref{https://xkcd.com/378}.
 
 @findex doctor

doc/emacs/msdos.texi

@@ -19,6 +19,13 @@ manual (@pxref{MS-DOS,,, emacs-xtra, Specialized Emacs Features}).
 section (@pxref{MS-DOS}).
 @end ifnottex
 
+  MS-Windows is a non-free operating system; that means it denies its
+users the freedom that every computer user deserves.  That is an
+injustice.  For your freedom's sake, we urge you to switch to a free
+operating system.
+
+  We support GNU Emacs on proprietary operating systems because we
+hope this taste of freedom will inspire users to escape from them.
 
   The behavior of Emacs on MS-Windows is reasonably similar to what is
 documented in the rest of the manual, including support for long file

doc/emacs/picture-xtra.texi

@@ -262,7 +262,14 @@ Clear out the region-rectangle with spaces
 text.
 @item C-c C-w @var{r}
 Similar, but save rectangle contents in register @var{r} first
-(@code{picture-clear-rectangle-to-register}).  @xref{Registers}.
+(@code{picture-clear-rectangle-to-register}).
+@iftex
+@xref{Registers,,, emacs, the Emacs Manual}.
+@end iftex
+@ifnottex
+@xref{Registers}.
+@end ifnottex
+
 @item C-c C-y
 Copy last killed rectangle into the buffer by overwriting, with upper
 left corner at point (@code{picture-yank-rectangle}).  With argument,

doc/lispref/control.texi

@@ -317,7 +317,8 @@ list of the form @code{(@var{pattern} @var{body-forms}@dots{})}.
 @var{pattern} of each clause, in textual order.  If the value matches,
 the clause succeeds; @code{pcase} then evaluates its @var{body-forms},
 and returns the value of the last of @var{body-forms}.  Any remaining
-@var{clauses} are ignored.
+@var{clauses} are ignored.  If no clauses match, then the @code{pcase}
+form evaluates to @code{nil}.
 
 The @var{pattern} part of a clause can be of one of two types:
 @dfn{QPattern}, a pattern quoted with a backquote; or a

lisp/emacs-lisp/pcase.el

@@ -118,7 +118,9 @@ two element list, binding its elements to symbols named `foo' and
 
 A significant difference from `cl-destructuring-bind' is that, if
 a pattern match fails, the next case is tried until either a
-successful match is found or there are no more cases.
+successful match is found or there are no more cases.  The CODE
+expression corresponding to the matching pattern determines the
+return value.  If there is no match the returned value is nil.
 
 Another difference is that pattern elements may be quoted,
 meaning they must match exactly: The pattern \\='(foo bar)
@@ -211,7 +213,8 @@ Emacs Lisp manual for more information and examples."
 
 ;;;###autoload
 (defmacro pcase-exhaustive (exp &rest cases)
-  "The exhaustive version of `pcase' (which see)."
+  "The exhaustive version of `pcase' (which see).
+If EXP fails to match any of the patterns in CASES, an error is signaled."
   (declare (indent 1) (debug pcase))
   (let* ((x (gensym "x"))
          (pcase--dontwarn-upats (cons x pcase--dontwarn-upats)))

lisp/net/shr.el

@@ -934,8 +934,12 @@ size, and full-buffer size."
   (shr-browse-url))
 
 (defun shr-browse-url (&optional external mouse-event)
-  "Browse the URL under point.
-If EXTERNAL, browse the URL using `shr-external-browser'."
+  "Browse the URL at point using `browse-url'.
+If EXTERNAL is non-nil (interactively, the prefix argument), browse
+the URL using `shr-external-browser'.
+If this function is invoked by a mouse click, it will browse the URL
+at the position of the click.  Optional argument MOUSE-EVENT describes
+the mouse click event."
   (interactive (list current-prefix-arg last-nonmenu-event))
   (mouse-set-point mouse-event)
   (let ((url (get-text-property (point) 'shr-url)))

lisp/subr.el

@@ -768,7 +768,9 @@ side-effects, and the argument LIST is not modified."
 KEYS should be a string in the format returned by commands such
 as `C-h k' (`describe-key').
 This is the same format used for saving keyboard macros (see
-`edmacro-mode')."
+`edmacro-mode').
+
+For an approximate inverse of this, see `key-description'."
   ;; Don't use a defalias, since the `pure' property is only true for
   ;; the calling convention of `kbd'.
   (read-kbd-macro keys))