[Emacs-diffs] /srv/bzr/emacs/emacs-24 r108031: Fix whitespace highlighting of context diffs.

[Chong Yidong]

------------------------------------------------------------
revno: 108031
fixes bug: http://debbugs.gnu.org/8612
committer: Chong Yidong <address@hidden>
branch nick: trunk
timestamp: Wed 2012-04-25 23:06:51 +0800
message:
  Fix whitespace highlighting of context diffs.
  
  * lisp/vc/diff-mode.el (diff-setup-whitespace): New function.
  (diff-mode): Use it.
  
  * lisp/vc/diff.el (diff-sentinel):
  * lisp/vc/vc.el (vc-diff-finish): Call diff-setup-whitespace to assign
  Whitespace mode variables based on diff style.
modified:
  lisp/ChangeLog
  lisp/vc/diff-mode.el
  lisp/vc/diff.el
  lisp/vc/vc.el

=== modified file 'lisp/ChangeLog'
--- a/lisp/ChangeLog    2012-04-25 14:47:33 +0000
+++ b/lisp/ChangeLog    2012-04-25 15:06:51 +0000
@@ -1,3 +1,12 @@
+2012-04-25  Chong Yidong  <address@hidden>
+
+       * vc/diff-mode.el (diff-setup-whitespace): New function.
+       (diff-mode): Use it.
+
+       * vc/diff.el (diff-sentinel):
+       * vc/vc.el (vc-diff-finish): Call diff-setup-whitespace to assign
+       Whitespace mode variables based on diff style (Bug#8612).
+
 2012-04-25  Leo Liu  <address@hidden>
 
        * files.el (auto-mode-alist): Use javascript-mode instead.

=== modified file 'lisp/vc/diff-mode.el'
--- a/lisp/vc/diff-mode.el      2012-04-14 06:28:57 +0000
+++ b/lisp/vc/diff-mode.el      2012-04-25 15:06:51 +0000
@@ -1283,11 +1283,7 @@
   (set (make-local-variable 'end-of-defun-function)
        'diff-end-of-file)
 
-  ;; Set up `whitespace-mode' so that turning it on will show trailing
-  ;; whitespace problems on the modified lines of the diff.
-  (set (make-local-variable 'whitespace-style) '(face trailing))
-  (set (make-local-variable 'whitespace-trailing-regexp)
-       "^[-\+!<>].*?\\([\t ]+\\)$")
+  (diff-setup-whitespace)
 
   (setq buffer-read-only diff-default-read-only)
   ;; setup change hooks
@@ -1332,6 +1328,22 @@
 
 ;;; Handy hook functions ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+(defun diff-setup-whitespace ()
+  "Set up Whitespace mode variables for the current Diff mode buffer.
+This sets `whitespace-style' and `whitespace-trailing-regexp' so
+that Whitespace mode shows trailing whitespace problems on the
+modified lines of the diff."
+  (set (make-local-variable 'whitespace-style) '(face trailing))
+  (let ((style (save-excursion
+                (goto-char (point-min))
+                (when (re-search-forward diff-hunk-header-re nil t)
+                  (goto-char (match-beginning 0))
+                  (diff-hunk-style)))))
+    (set (make-local-variable 'whitespace-trailing-regexp)
+        (if (eq style 'context)
+            "^[-\+!] .*?\\([\t ]+\\)$"
+          "^[-\+!<>].*?\\([\t ]+\\)$"))))
+
 (defun diff-delete-if-empty ()
   ;; An empty diff file means there's no more diffs to integrate, so we
   ;; can just remove the file altogether.  Very handy for .rej files if we

=== modified file 'lisp/vc/diff.el'
--- a/lisp/vc/diff.el   2012-01-19 07:21:25 +0000
+++ b/lisp/vc/diff.el   2012-04-25 15:06:51 +0000
@@ -30,6 +30,8 @@
 
 ;;; Code:
 
+(declare-function diff-setup-whitespace "diff-mode" ())
+
 (eval-when-compile (require 'cl))
 
 (defgroup diff nil
@@ -64,6 +66,7 @@
 delete the temporary files so named."
   (if old-temp-file (delete-file old-temp-file))
   (if new-temp-file (delete-file new-temp-file))
+  (diff-setup-whitespace)
   (save-excursion
     (goto-char (point-max))
     (let ((inhibit-read-only t))

=== modified file 'lisp/vc/vc.el'
--- a/lisp/vc/vc.el     2012-04-22 13:58:00 +0000
+++ b/lisp/vc/vc.el     2012-04-25 15:06:51 +0000
@@ -655,6 +655,8 @@
 (require 'vc-dispatcher)
 (require 'ediff)
 
+(declare-function diff-setup-whitespace "diff-mode" ())
+
 (eval-when-compile
   (require 'cl)
   (require 'dired))
@@ -1524,17 +1526,18 @@
   ;; possibility of an empty output is for an async process.
   (when (buffer-live-p buffer)
     (let ((window (get-buffer-window buffer t))
-          (emptyp (zerop (buffer-size buffer))))
+         (emptyp (zerop (buffer-size buffer))))
       (with-current-buffer buffer
-        (and messages emptyp
-             (let ((inhibit-read-only t))
-               (insert (cdr messages) ".\n")
-               (message "%s" (cdr messages))))
-        (goto-char (point-min))
-        (when window
-          (shrink-window-if-larger-than-buffer window)))
+       (and messages emptyp
+            (let ((inhibit-read-only t))
+              (insert (cdr messages) ".\n")
+              (message "%s" (cdr messages))))
+       (diff-setup-whitespace)
+       (goto-char (point-min))
+       (when window
+         (shrink-window-if-larger-than-buffer window)))
       (when (and messages (not emptyp))
-        (message "%sdone" (car messages))))))
+       (message "%sdone" (car messages))))))
 
 (defvar vc-diff-added-files nil
   "If non-nil, diff added files by comparing them to /dev/null.")