vc-hg.el: New file.

2 files changed, 400 insertions, 0 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index adfef8ab290..9076e32c49b 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2007-07-06  Dan Nicolaescu  <dann@ics.uci.edu>
+
+        * vc-hg.el: New file.
+
 2007-07-06  Andreas Schwab  <schwab@suse.de>
 
         * emacs-lisp/lisp-mode.el (eval-last-sexp): Avoid introducing any
diff --git a/lisp/vc-hg.el b/lisp/vc-hg.el
new file mode 100644
index 00000000000..ec4f2e7d1ef
--- /dev/null
+++ b/lisp/vc-hg.el
@@ -0,0 +1,396 @@
+;;; vc-hg.el --- VC backend for the mercurial version control system
+
+;; Copyright (C) 2006, 2007 Free Software Foundation, Inc.
+
+;; Author: Ivan Kanis
+;; Keywords: tools
+;; Version: 1889
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 2, or (at your option)
+;; any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs; see the file COPYING.  If not, write to the
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
+
+;;; Commentary:
+
+;; This is a mercurial version control backend
+
+;;; Thanks:
+
+;;; Bugs:
+
+;;; Installation:
+
+;;; Todo:
+
+;; Implement the rest of the vc interface. See the comment at the
+;; beginning of vc.el. The current status is:
+
+;; FUNCTION NAME                               STATUS
+;; * registered (file)                         OK
+;; * state (file)                              OK
+;; - state-heuristic (file)                    ?? PROBABLY NOT NEEDED
+;; - dir-state (dir)                           NEEDED
+;; * workfile-version (file)                   OK
+;; - latest-on-branch-p (file)                 ??
+;; * checkout-model (file)                     OK
+;; - workfile-unchanged-p (file)               ??
+;; - mode-line-string (file)                   NOT NEEDED
+;; - dired-state-info (file)                   NEEDED
+;; STATE-CHANGING FUNCTIONS
+;; * register (file &optional rev comment)     OK
+;; - init-version ()                           NOT NEEDED
+;; - responsible-p (file)                      OK
+;; - could-register (file)                     OK
+;; - receive-file (file rev)                   ?? PROBABLY NOT NEEDED
+;; - unregister (file)                         COMMENTED OUT, MAY BE INCORRECT
+;; * checkin (file rev comment)                OK
+;; * find-version (file rev buffer)            OK
+;; * checkout (file &optional editable rev)    NOT NEEDED, COMMENTED OUT
+;; * revert (file &optional contents-done)     OK
+;; - cancel-version (file editable)            ?? PROBABLY NOT NEEDED   
+;; - merge (file rev1 rev2)                    NEEDED
+;; - merge-news (file)                         NEEDED
+;; - steal-lock (file &optional version)       NOT NEEDED
+;; HISTORY FUNCTIONS
+;; * print-log (file &optional buffer)         OK
+;; - log-view-mode ()                          OK
+;; - show-log-entry (version)                  NOT NEEDED, DEFAULT IS GOOD
+;; - wash-log (file)                           ??
+;; - logentry-check ()                         NOT NEEDED
+;; - comment-history (file)                    NOT NEEDED
+;; - update-changelog (files)                  NOT NEEDED
+;; * diff (file &optional rev1 rev2 buffer)    OK
+;; - revision-completion-table (file)          ??
+;; - diff-tree (dir &optional rev1 rev2)       TEST IT
+;; - annotate-command (file buf &optional rev) OK
+;; - annotate-time ()                          OK
+;; - annotate-current-time ()                  ?? NOT NEEDED
+;; - annotate-extract-revision-at-line ()      OK
+;; SNAPSHOT SYSTEM
+;; - create-snapshot (dir name branchp)        NEEDED (probably branch?)
+;; - assign-name (file name)                   NOT NEEDED
+;; - retrieve-snapshot (dir name update)       ?? NEEDED??
+;; MISCELLANEOUS
+;; - make-version-backups-p (file)             ??
+;; - repository-hostname (dirname)             ?? 
+;; - previous-version (file rev)               OK
+;; - next-version (file rev)                   OK
+;; - check-headers ()                          ??
+;; - clear-headers ()                          ??
+;; - delete-file (file)                        TEST IT
+;; - rename-file (old new)                     OK
+;; - find-file-hook ()                         PROBABLY NOT NEEDED
+;; - find-file-not-found-hook ()               PROBABLY NOT NEEDED
+
+;; Implement Stefan Monnier's advice:
+;; vc-hg-registered and vc-hg-state
+;; Both of those functions should be super extra careful to fail gracefully in
+;; unexpected circumstances. The reason this is important is that any error
+;; there will prevent the user from even looking at the file :-(
+;; Ideally, just like in vc-arch and vc-cvs, checking that the file is under
+;; mercurial's control and extracting the current revision should be done
+;; without even using `hg' (this way even if you don't have `hg' installed,
+;; Emacs is able to tell you this file is under mercurial's control).
+
+;;; History:
+;;
+
+;;; Code:
+
+(eval-when-compile
+  (require 'vc))
+
+;; XXX This should be moved to vc-hooks after this gets a bit more
+;; testing in the trunk.
+(add-to-list 'vc-handled-backends 'HG)
+
+;;; Customization options
+
+(defcustom vc-hg-global-switches nil
+  "*Global switches to pass to any Hg command."
+  :type '(choice (const :tag "None" nil)
+         (string :tag "Argument String")
+         (repeat :tag "Argument List"
+             :value ("")
+             string))
+  :version "22.2"
+  :group 'vc)
+
+;;; State querying functions
+
+;;;###autoload (defun vc-hg-registered (file)
+;;;###autoload   "Return non-nil if FILE is registered with hg."
+;;;###autoload   (if (vc-find-root file ".hg")       ; short cut
+;;;###autoload       (progn
+;;;###autoload         (load "vc-hg")
+;;;###autoload         (vc-hg-registered file))))
+
+;; Modelled after the similar function in vc-bzr.el
+(defun vc-hg-registered (file)
+  "Return non-nil if FILE is registered with hg."
+  (if (vc-hg-root file)               ; short cut
+      (vc-hg-state file)))            ; expensive
+
+(defun vc-hg-state (file)
+  "Hg-specific version of `vc-state'."
+  (let* 
+      ((status nil)
+       (out
+        (with-output-to-string
+          (with-current-buffer
+              standard-output
+            (setq status
+                  (condition-case nil
+                      ;; Ignore all errors.
+                      (call-process
+                       "hg" nil t nil "--cwd" (file-name-directory file)
+                       "status" (file-name-nondirectory file))
+                    ;; Some problem happened.  E.g. We can't find an `hg'
+                    ;; executable.
+                    (error nil)))))))
+    (when (eq 0 status)
+      (if (eq 0 (length out)) 'up-to-date
+        (let ((state (aref out 0)))
+          (cond
+           ((eq state ?M) 'edited)
+           ((eq state ?A) 'edited)
+           ((eq state ?P) 'needs-patch)
+           ((eq state ??) nil)
+           (t 'up-to-date)))))))
+
+(defun vc-hg-workfile-version (file)
+  "Hg-specific version of `vc-workfile-version'."
+  (let* 
+      ((status nil)
+       (out
+        (with-output-to-string
+          (with-current-buffer
+              standard-output
+            (setq status
+                  (condition-case nil
+                      ;; Ignore all errors.
+                      (call-process
+                       "hg" nil t nil "--cwd" (file-name-directory file)
+                       "log" "-l1" (file-name-nondirectory file))
+                    ;; Some problem happened.  E.g. We can't find an `hg'
+                    ;; executable.
+                    (error nil)))))))
+    (when (eq 0 status)
+      (if (string-match "changeset: *\\([0-9]*\\)" out)
+          (match-string 1 out)
+        "0"))))
+
+;;; History functions
+
+(defun vc-hg-print-log(file &optional buffer)
+  "Get change log associated with FILE."
+  ;; `log-view-mode' needs to have the file name in order to function
+  ;; correctly. "hg log" does not print it, so we insert it here by
+  ;; hand.
+
+  ;; `vc-do-command' creates the buffer, but we need it before running
+  ;; the command.
+  (vc-setup-buffer buffer)
+  ;; If the buffer exists from a previous invocation it might be
+  ;; read-only.
+  (let ((inhibit-read-only t))
+    (with-current-buffer
+        buffer
+      (insert "File:        " (file-name-nondirectory file) "\n")))
+  (vc-hg-command
+   buffer
+   (if (and (vc-stay-local-p file) (fboundp 'start-process)) 'async 0)
+   file "log"))
+
+(defvar log-view-message-re)
+(defvar log-view-file-re)
+(defvar log-view-font-lock-keywords)
+
+(define-derived-mode vc-hg-log-view-mode log-view-mode "HG-Log-View"
+  (require 'add-log) ;; we need the faces add-log
+  ;; Don't have file markers, so use impossible regexp.
+  (set (make-local-variable 'log-view-file-re) "^File:[ \t]+\\(.+\\)")
+  (set (make-local-variable 'log-view-message-re)
+       "^changeset:[ \t]*\\([0-9]+\\):\\(.+\\)")
+  (set (make-local-variable 'log-view-font-lock-keywords)
+       (append
+        log-view-font-lock-keywords
+        ;; Handle the case:
+        ;; user: foo@bar
+        '(("^user:[ \t]+\\([A-Za-z0-9_.+-]+@[A-Za-z0-9_.-]+\\)"
+           (1 'change-log-email))
+          ;; Handle the case:
+          ;; user: FirstName LastName <foo@bar>
+          ("^user:[ \t]+\\([^<(]+?\\)[ \t]*[(<]\\([A-Za-z0-9_.+-]+@[A-Za-z0-9_.-]+\\)[>)]"
+           (1 'change-log-name)
+           (2 'change-log-email))
+          ("^date: \\(.+\\)" (1 'change-log-date))
+          ("^summary:[ \t]+\\(.+\\)" (1 'log-view-message))))))
+
+(defun vc-hg-diff (file &optional oldvers newvers buffer)
+  "Get a difference report using hg between two versions of FILE."
+  (let ((working (vc-workfile-version file)))
+    (if (and (equal oldvers working) (not newvers))
+        (setq oldvers nil))
+    (if (and (not oldvers) newvers)
+        (setq oldvers working))
+    (apply 'call-process "hg" nil (or buffer "*vc-diff*") nil
+           "--cwd" (file-name-directory file) "diff"
+           (append
+            (if oldvers
+                (if newvers
+                    (list "-r" oldvers "-r" newvers)
+                  (list "-r" oldvers))
+              (list ""))
+            (list (file-name-nondirectory file))))))
+
+(defalias 'vc-hg-diff-tree 'vc-hg-diff)
+
+(defun vc-hg-annotate-command (file buffer &optional version)
+  "Execute \"hg annotate\" on FILE, inserting the contents in BUFFER.
+Optional arg VERSION is a version to annotate from."
+  (vc-hg-command buffer 0 file "annotate" "-d" "-n" (if version (concat "-r" version)))
+  (with-current-buffer buffer
+    (goto-char (point-min))
+    (re-search-forward "^[0-9]")
+    (delete-region (point-min) (1- (point)))))
+
+
+;; The format for one line output by "hg annotate -d -n" looks like this:
+;;215 Wed Jun 20 21:22:58 2007 -0700: CONTENTS
+;; i.e: VERSION_NUMBER DATE: CONTENTS
+(defconst vc-hg-annotate-re "^[ \t]*\\([0-9]+\\) \\(.\\{30\\}\\): ")
+
+(defun vc-hg-annotate-time ()
+  (when (looking-at vc-hg-annotate-re)
+    (goto-char (match-end 0))
+    (vc-annotate-convert-time
+     (date-to-time (match-string-no-properties 2)))))
+
+(defun vc-hg-annotate-extract-revision-at-line ()
+  (save-excursion
+    (beginning-of-line)
+    (if (looking-at vc-hg-annotate-re) (match-string-no-properties 1))))
+
+(defun vc-hg-previous-version (file rev)
+  (let ((newrev (1- (string-to-number rev))))
+    (when (>= newrev 0)
+      (number-to-string newrev))))
+
+(defun vc-hg-next-version (file rev)
+  (let ((newrev (1+ (string-to-number rev)))
+        (tip-version 
+         (with-temp-buffer
+           (vc-hg-command t nil nil "tip")
+           (goto-char (point-min))
+           (re-search-forward "^changeset:[ \t]*\\([0-9]+\\):")
+           (string-to-number (match-string-no-properties 1)))))
+    ;; We don't want to exceed the maximum possible version number, ie
+    ;; the tip version.
+    (when (<= newrev tip-version)
+      (number-to-string newrev))))
+
+;; Modelled after the similar function in vc-bzr.el
+(defun vc-hg-delete-file (file)
+  "Delete FILE and delete it in the hg repository."
+  (condition-case ()
+      (delete-file file)
+    (file-error nil))
+  (vc-hg-command nil nil file "remove" "--after" "--force"))
+
+;; Modelled after the similar function in vc-bzr.el
+(defun vc-hg-rename-file (old new)
+  "Rename file from OLD to NEW using `hg mv'."
+  (vc-hg-command nil nil new old "mv"))
+
+(defun vc-hg-register (file &optional rev comment)
+  "Register FILE under hg.
+REV is ignored.
+COMMENT is ignored."
+  (vc-hg-command nil nil file "add"))
+
+(defalias 'vc-hg-responsible-p 'vc-hg-root)
+
+;; Modelled after the similar function in vc-bzr.el
+(defun vc-hg-could-register (file)
+  "Return non-nil if FILE could be registered under hg."
+  (and (vc-hg-responsible-p file)      ; shortcut
+       (condition-case ()
+           (with-temp-buffer
+             (vc-hg-command t nil file "add" "--dry-run"))
+             ;; The command succeeds with no output if file is
+             ;; registered.
+         (error))))
+
+;; XXX This would remove the file. Is that correct?
+;; (defun vc-hg-unregister (file)
+;;   "Unregister FILE from hg."
+;;   (vc-hg-command nil nil file "remove"))
+
+(defun vc-hg-checkin (file rev comment)
+  "HG-specific version of `vc-backend-checkin'.
+REV is ignored."
+  (vc-hg-command nil nil file  "commit" "-m" comment))
+
+(defun vc-hg-find-version (file rev buffer)
+  (let ((coding-system-for-read 'binary)
+        (coding-system-for-write 'binary))
+    (if rev
+        (vc-hg-command buffer nil file "cat" "-r" rev)
+      (vc-hg-command buffer nil file "cat"))))
+
+;; Modelled after the similar function in vc-bzr.el
+;; This should not be needed, `vc-hg-find-version' provides the same
+;; functionality.
+;; (defun vc-hg-checkout (file &optional editable rev workfile)
+;;   "Retrieve a revision of FILE into a WORKFILE.
+;; EDITABLE is ignored.
+;; REV is the revision to check out into WORKFILE."
+;;   (unless workfile
+;;     (setq workfile (vc-version-backup-file-name file rev)))
+;;   (let ((coding-system-for-read 'binary)
+;;         (coding-system-for-write 'binary))
+;;   (with-temp-file workfile
+;;     (if rev
+;;         (vc-hg-command t nil file "cat" "-r" rev)
+;;       (vc-hg-command t nil file "cat")))))
+
+(defun vc-hg-checkout-model (file)
+  'implicit)
+
+;; Modelled after the similar function in vc-bzr.el
+(defun vc-hg-revert (file &optional contents-done)
+  (unless contents-done
+    (with-temp-buffer (vc-hg-command t nil file "revert"))))
+
+;;; Internal functions
+
+(defun vc-hg-command (buffer okstatus file &rest flags)
+  "A wrapper around `vc-do-command' for use in vc-hg.el.
+The difference to vc-do-command is that this function always invokes `hg',
+and that it passes `vc-hg-global-switches' to it before FLAGS."
+  (apply 'vc-do-command buffer okstatus "hg" file
+         (if (stringp vc-hg-global-switches)
+             (cons vc-hg-global-switches flags)
+           (append vc-hg-global-switches
+                   flags))))
+
+(defun vc-hg-root (file)
+  (vc-find-root file ".hg"))
+
+(provide 'vc-hg)
+
+;;; vc-hg.el ends here