* lisp/files.el: Use a fixed file name for the second dir-locals file

(dir-locals-file): Revert to its original fixed value.
(dir-locals-file-2): New const.
(dir-locals--all-files): Don't use `file-name-all-completions'.
Instead, just check for the 2 dir-locals files and return a list
of the ones that exit (if any).

* etc/NEWS: Document the change.

* doc/emacs/custom.texi (Directory Variables): Document the change.

* doc/lispref/variables.texi (Directory Local Variables): Update
accordingly.

2 files changed, 15 insertions, 28 deletions

diff --git a/doc/emacs/custom.texi b/doc/emacs/custom.texi
index 670848c65a1..7be660c85d1 100644
--- a/doc/emacs/custom.texi
+++ b/doc/emacs/custom.texi
@@ -1299,8 +1299,8 @@ named @file{.dir-locals.el}@footnote{ On MS-DOS, the name of this file
 should be @file{_dir-locals.el}, due to limitations of the DOS
 filesystems.  If the filesystem is limited to 8+3 file names, the name
 of the file will be truncated by the OS to @file{_dir-loc.el}.
-}@footnote{ You can also use files like @file{.dir-locals2.el}, which
-are loaded in addition.  This is useful when @file{.dir-locals.el} is
+}@footnote{ You can also use @file{.dir-locals-2.el}, which
+is loaded in addition.  This is useful when @file{.dir-locals.el} is
 under version control in a shared repository and can't be used for
 personal customizations.  } in a
 directory.  Whenever Emacs visits any file in that directory or any of
diff --git a/doc/lispref/variables.texi b/doc/lispref/variables.texi
index 42701614365..6c53e9b6cca 100644
--- a/doc/lispref/variables.texi
+++ b/doc/lispref/variables.texi
@@ -1765,33 +1765,20 @@ variables: by putting them in a special file, or by defining a
 @dfn{project class} for that directory.
 
 @defvr Constant dir-locals-file
-This constant is a wildcard pattern matching the name of files where
-Emacs expects to find directory-local variables.  Its value is
-@file{.dir-locals*.el}@footnote{
-The MS-DOS version of Emacs uses @file{_dir-locals*.el} instead, due to
+This constant is the name of the file where Emacs expects to find the
+directory-local variables.  The name of the file is
+@file{.dir-locals.el}@footnote{
+The MS-DOS version of Emacs uses @file{_dir-locals.el} instead, due to
 limitations of the DOS filesystems.
-}, and the most common file name to use is @file{.dir-locals.el}.
-
-Any file matching this name pattern in a directory causes Emacs to
-apply its settings when visiting files in that directory or any of its
-subdirectories (optionally, you can exclude subdirectories; see
-below).
-If some of the subdirectories have their own file matching
-@file{.dir-locals*.el}, Emacs uses the settings from the deepest file
-it finds starting from the file's directory and moving up the
-directory tree.  The file specifies local variables as a specially
-formatted list; see @ref{Directory Variables, , Per-directory Local
-Variables, emacs, The GNU Emacs Manual}, for more details.
-
-If the same directory contains multiple such files (for instance,
-@file{.dir-locals.el} and @file{.dir-locals2.el}), then all of them
-are used in @code{string<} order.  This means that, if two files
-specify different values for the same variable, the file sorted after
-will override the value of the previous file (for instance, values in
-@file{.dir-locals2.el} override those in @file{.dir-locals.el}).  Note
-that, because of how lexicographic order works, values in
-@file{.dir-locals10.el} are overridden by values in @file{.dir-locals2.el}.
-This can be avoided by using @file{.dir-locals02.el} instead.
+}.  A file by that name in a directory causes Emacs to apply its
+settings to any file in that directory or any of its subdirectories
+(optionally, you can exclude subdirectories; see below).
+If some of the subdirectories have their own @file{.dir-locals.el}
+files, Emacs uses the settings from the deepest file it finds starting
+from the file's directory and moving up the directory tree.  The file
+specifies local variables as a specially formatted list; see
+@ref{Directory Variables, , Per-directory Local Variables, emacs, The
+GNU Emacs Manual}, for more details.
 @end defvr
 
 @defun hack-dir-local-variables