master d8924e179e: Extend file-expand-wildcards to allow regexps

[Lars Ingebrigtsen]

branch: master
commit d8924e179e2e53bf9abffa987f428890b4edcf57
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Extend file-expand-wildcards to allow regexps
    
    * doc/lispref/files.texi (Contents of Directories): Document it.
    * lisp/files.el (file-expand-wildcards): Extend to allow regexps.
    
    * lisp/emacs-lisp/shortdoc.el (file): Expand the
    file-expand-wildcards example.
---
 doc/lispref/files.texi      |  8 +++++++-
 etc/NEWS                    |  3 +++
 lisp/emacs-lisp/shortdoc.el |  4 +++-
 lisp/files.el               | 23 +++++++++++++++++------
 4 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/doc/lispref/files.texi b/doc/lispref/files.texi
index 75905658e6..d473261026 100644
--- a/doc/lispref/files.texi
+++ b/doc/lispref/files.texi
@@ -3112,10 +3112,16 @@ except those two.  It is useful as the 
@var{match-regexp} argument to
 returns @code{nil}, if directory @samp{/foo} is empty.
 @end defvr
 
-@defun file-expand-wildcards pattern &optional full
+@defun file-expand-wildcards pattern &optional full regexp
 This function expands the wildcard pattern @var{pattern}, returning
 a list of file names that match it.
 
+@var{pattern} is, by default, a ``glob''/wildcard string, e.g.,
+@samp{"/tmp/*.png"} or @samp{"/*/*/foo.png"}, but can also be a
+regular expression if the optional @var{regexp} parameter is non-nil.
+In any case, the matches are applied per sub-directory, so a match
+can't span a parent/sub directory.
+
 If @var{pattern} is written as an absolute file name,
 the values are absolute also.
 
diff --git a/etc/NEWS b/etc/NEWS
index 551aea411e..a46bf850b1 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -1936,6 +1936,9 @@ Previously it produced a nonsense value, -1, that was 
never intended.
 
 * Lisp Changes in Emacs 29.1
 
++++
+** 'file-expand-wildcards' can now also take a regexp match.
+
 ---
 ** vc-mtn (the backend for Monotone) has been made obsolete.
 
diff --git a/lisp/emacs-lisp/shortdoc.el b/lisp/emacs-lisp/shortdoc.el
index 92b9c1dd32..a1256ce1b8 100644
--- a/lisp/emacs-lisp/shortdoc.el
+++ b/lisp/emacs-lisp/shortdoc.el
@@ -468,7 +468,9 @@ A FUNC form can have any number of `:no-eval' (or 
`:no-value'),
    :no-eval* (directory-files-and-attributes "/tmp/foo"))
   (file-expand-wildcards
    :no-eval (file-expand-wildcards "/tmp/*.png")
-   :eg-result ("/tmp/foo.png" "/tmp/zot.png"))
+   :eg-result ("/tmp/foo.png" "/tmp/zot.png")
+   :no-eval (file-expand-wildcards "/*/foo.png")
+   :eg-result ("/tmp/foo.png" "/var/foo.png"))
   (locate-dominating-file
    :no-eval (locate-dominating-file "foo.png" "/tmp/foo/bar/zot")
    :eg-result "/tmp/foo.png")
diff --git a/lisp/files.el b/lisp/files.el
index b5da0ea5c5..95f5b2c535 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -7198,13 +7198,21 @@ by `sh' are supported."
   :type 'string
   :group 'dired)
 
-(defun file-expand-wildcards (pattern &optional full)
+(defun file-expand-wildcards (pattern &optional full regexp)
   "Expand wildcard pattern PATTERN.
 This returns a list of file names that match the pattern.
-Files are sorted in `string<' order.
 
-If PATTERN is written as an absolute file name,
-the values are absolute also.
+PATTERN is, by default, a \"glob\"/wildcard string, e.g.,
+\"/tmp/*.png\" or \"/*/*/foo.png\", but can also be a regular
+expression if the optional REGEXP parameter is non-nil.  In any
+case, the matches are applied per sub-directory, so a match can't
+span a parent/sub directory, which means that a regexp bit can't
+contain the \"/\" character.
+
+The list of files returned are sorted in `string<' order.
+
+If PATTERN is written as an absolute file name, the values are
+absolute also.
 
 If PATTERN is written as a relative file name, it is interpreted
 relative to the current default directory, `default-directory'.
@@ -7219,7 +7227,8 @@ default directory.  However, if FULL is non-nil, they are 
absolute."
           (dirs (if (and dirpart
                          (string-match "[[*?]" (file-local-name dirpart)))
                     (mapcar 'file-name-as-directory
-                            (file-expand-wildcards (directory-file-name 
dirpart)))
+                            (file-expand-wildcards
+                              (directory-file-name dirpart) nil regexp))
                   (list dirpart)))
           contents)
       (dolist (dir dirs)
@@ -7233,7 +7242,9 @@ default directory.  However, if FULL is non-nil, they are 
absolute."
                                                        (file-name-nondirectory 
name))
                                    name))
                               (directory-files (or dir ".") full
-                                               (wildcard-to-regexp nondir))))))
+                                                (if regexp
+                                                    nondir
+                                                 (wildcard-to-regexp 
nondir)))))))
            (setq contents
                  (nconc
                   (if (and dir (not full))