Update docs for `customize-mode'

[gnu-emacs] / lisp / version.el

diff --git a/lisp/version.el b/lisp/version.el
index 43103fde13119d4fe2092950c6118051c93c6461..77188a51ee3b03e5f5895b85a2a89fe406805937 100644 (file)
--- a/lisp/version.el
+++ b/lisp/version.el
@@ -1,6 +1,6 @@
 ;;; version.el --- record version number of Emacs
 
-;; Copyright (C) 1985, 1992, 1994-1995, 1999-2015 Free Software
+;; Copyright (C) 1985, 1992, 1994-1995, 1999-2016 Free Software
 ;; Foundation, Inc.
 
 ;; Maintainer: emacs-devel@gnu.org
@@ -113,17 +113,17 @@ or if we could not determine the revision.")
                  (looking-at "[0-9a-fA-F]\\{40\\}"))
           (match-string 0)))))
 
-(defun emacs-repository--version-git-1 (file)
+(defun emacs-repository--version-git-1 (file dir)
   "Internal subroutine of `emacs-repository-get-version'."
   (when (file-readable-p file)
-    (erase-buffer)
-    (insert-file-contents file)
-    (cond ((looking-at "[0-9a-fA-F]\\{40\\}")
-          (match-string 0))
-         ((looking-at "ref: \\(.*\\)")
-          (emacs-repository--version-git-1
-           (expand-file-name (match-string 1)
-                             (file-name-directory file)))))))
+    (with-temp-buffer
+      (insert-file-contents file)
+      (cond ((looking-at "[0-9a-fA-F]\\{40\\}")
+             (match-string 0))
+            ((looking-at "ref: \\(.*\\)")
+             (emacs-repository--version-git-1
+              (expand-file-name (match-string 1) dir)
+              dir))))))
 
 (defun emacs-repository-get-version (&optional dir external)
   "Try to return as a string the repository revision of the Emacs sources.
@@ -138,20 +138,38 @@ Optional argument EXTERNAL non-nil means to just ask the VCS itself,
 if the sources appear to be under version control.  Otherwise only ask
 the VCS if we cannot find any information ourselves."
   (or dir (setq dir source-directory))
-  (when (file-directory-p (expand-file-name ".git" dir))
-    (if external
-       (emacs-repository-version-git dir)
-      (or (let ((files '("HEAD" "refs/heads/master"))
-               file rev)
-           (with-temp-buffer
-             (while (and (not rev)
-                         (setq file (car files)))
-               (setq file (expand-file-name (format ".git/%s" file) dir)
-                     files (cdr files)
-                     rev (emacs-repository--version-git-1 file))))
-           rev)
-         ;; AFAICS this doesn't work during dumping (bug#20799).
-         (emacs-repository-version-git dir)))))
+  (let* ((base-dir (expand-file-name ".git" dir))
+         (in-main-worktree (file-directory-p base-dir))
+         (in-linked-worktree nil)
+         sub-dir)
+    ;; If the sources are in a linked worktree, .git is a file that points to
+    ;; the location of the main worktree and the repo's administrative files.
+    (when (and (not in-main-worktree)
+               (file-regular-p base-dir)
+               (file-readable-p base-dir))
+      (with-temp-buffer
+        (insert-file-contents base-dir)
+        (when (looking-at "gitdir: \\(.*\.git\\)\\(.*\\)$")
+          (setq base-dir (match-string 1)
+                sub-dir (concat base-dir (match-string 2))
+                in-linked-worktree t))))
+    ;; We've found a worktree, either main or linked.
+    (when (or in-main-worktree in-linked-worktree)
+      (if external
+          (emacs-repository-version-git dir)
+        (or (if in-linked-worktree
+                (emacs-repository--version-git-1
+                 (expand-file-name "HEAD" sub-dir) base-dir)
+              (let ((files '("HEAD" "refs/heads/master"))
+                    file rev)
+                (while (and (not rev)
+                            (setq file (car files)))
+                  (setq file (expand-file-name file base-dir)
+                        files (cdr files)
+                        rev (emacs-repository--version-git-1 file base-dir)))
+                rev))
+            ;; AFAICS this doesn't work during dumping (bug#20799).
+            (emacs-repository-version-git dir))))))
 
 ;; We put version info into the executable in the form that `ident' uses.
 (purecopy (concat "\n$Id: " (subst-char-in-string ?\n ?\s (emacs-version))