From: Glenn Morris Date: Tue, 13 Sep 2011 21:02:27 +0000 (-0400) Subject: * lisp/emacs-lisp/debug.el (debugger-make-xrefs): Preserve point. (Bug#9462) X-Git-Tag: emacs-pretest-24.0.90~104^2~59 X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=8e39b2e837bb3de939eda51074b6c6f95aaef5f2;p=emacs.git * lisp/emacs-lisp/debug.el (debugger-make-xrefs): Preserve point. (Bug#9462) --- diff --git a/lisp/ChangeLog b/lisp/ChangeLog index 73384823c48..a689b696f2f 100644 --- a/lisp/ChangeLog +++ b/lisp/ChangeLog @@ -1,3 +1,8 @@ +2011-09-13 Glenn Morris + + * emacs-lisp/debug.el (debugger-make-xrefs): + Preserve point. (Bug#9462) + 2011-09-13 Chong Yidong * window.el (window-deletable-p): Use next-frame. diff --git a/lisp/emacs-lisp/debug.el b/lisp/emacs-lisp/debug.el index 8276030ccf8..6533721054c 100644 --- a/lisp/emacs-lisp/debug.el +++ b/lisp/emacs-lisp/debug.el @@ -342,71 +342,72 @@ That buffer should be current already." "Attach cross-references to function names in the `*Backtrace*' buffer." (interactive "b") (with-current-buffer (or buffer (current-buffer)) - (setq buffer (current-buffer)) - (let ((inhibit-read-only t) - (old-end (point-min)) (new-end (point-min))) - ;; If we saved an old backtrace, find the common part - ;; between the new and the old. - ;; Compare line by line, starting from the end, - ;; because that's the part that is likely to be unchanged. - (if debugger-previous-backtrace - (let (old-start new-start (all-match t)) - (goto-char (point-max)) - (with-temp-buffer - (insert debugger-previous-backtrace) - (while (and all-match (not (bobp))) - (setq old-end (point)) - (forward-line -1) - (setq old-start (point)) - (with-current-buffer buffer - (setq new-end (point)) - (forward-line -1) - (setq new-start (point))) - (if (not (zerop - (let ((case-fold-search nil)) - (compare-buffer-substrings - (current-buffer) old-start old-end - buffer new-start new-end)))) - (setq all-match nil)))) - ;; Now new-end is the position of the start of the - ;; unchanged part in the current buffer, and old-end is - ;; the position of that same text in the saved old - ;; backtrace. But we must subtract (point-min) since strings are - ;; indexed in origin 0. - - ;; Replace the unchanged part of the backtrace - ;; with the text from debugger-previous-backtrace, - ;; since that already has the proper xrefs. - ;; With this optimization, we only need to scan - ;; the changed part of the backtrace. - (delete-region new-end (point-max)) - (goto-char (point-max)) - (insert (substring debugger-previous-backtrace - (- old-end (point-min)))) - ;; Make the unchanged part of the backtrace inaccessible - ;; so it won't be scanned. - (narrow-to-region (point-min) new-end))) - - ;; Scan the new part of the backtrace, inserting xrefs. - (goto-char (point-min)) - (while (progn - (goto-char (+ (point) 2)) - (skip-syntax-forward "^w_") - (not (eobp))) - (let* ((beg (point)) - (end (progn (skip-syntax-forward "w_") (point))) - (sym (intern-soft (buffer-substring-no-properties - beg end))) - (file (and sym (symbol-file sym 'defun)))) - (when file - (goto-char beg) - ;; help-xref-button needs to operate on something matched - ;; by a regexp, so set that up for it. - (re-search-forward "\\(\\sw\\|\\s_\\)+") - (help-xref-button 0 'help-function-def sym file))) - (forward-line 1)) - (widen)) - (setq debugger-previous-backtrace (buffer-string)))) + (save-excursion + (setq buffer (current-buffer)) + (let ((inhibit-read-only t) + (old-end (point-min)) (new-end (point-min))) + ;; If we saved an old backtrace, find the common part + ;; between the new and the old. + ;; Compare line by line, starting from the end, + ;; because that's the part that is likely to be unchanged. + (if debugger-previous-backtrace + (let (old-start new-start (all-match t)) + (goto-char (point-max)) + (with-temp-buffer + (insert debugger-previous-backtrace) + (while (and all-match (not (bobp))) + (setq old-end (point)) + (forward-line -1) + (setq old-start (point)) + (with-current-buffer buffer + (setq new-end (point)) + (forward-line -1) + (setq new-start (point))) + (if (not (zerop + (let ((case-fold-search nil)) + (compare-buffer-substrings + (current-buffer) old-start old-end + buffer new-start new-end)))) + (setq all-match nil)))) + ;; Now new-end is the position of the start of the + ;; unchanged part in the current buffer, and old-end is + ;; the position of that same text in the saved old + ;; backtrace. But we must subtract (point-min) since strings are + ;; indexed in origin 0. + + ;; Replace the unchanged part of the backtrace + ;; with the text from debugger-previous-backtrace, + ;; since that already has the proper xrefs. + ;; With this optimization, we only need to scan + ;; the changed part of the backtrace. + (delete-region new-end (point-max)) + (goto-char (point-max)) + (insert (substring debugger-previous-backtrace + (- old-end (point-min)))) + ;; Make the unchanged part of the backtrace inaccessible + ;; so it won't be scanned. + (narrow-to-region (point-min) new-end))) + + ;; Scan the new part of the backtrace, inserting xrefs. + (goto-char (point-min)) + (while (progn + (goto-char (+ (point) 2)) + (skip-syntax-forward "^w_") + (not (eobp))) + (let* ((beg (point)) + (end (progn (skip-syntax-forward "w_") (point))) + (sym (intern-soft (buffer-substring-no-properties + beg end))) + (file (and sym (symbol-file sym 'defun)))) + (when file + (goto-char beg) + ;; help-xref-button needs to operate on something matched + ;; by a regexp, so set that up for it. + (re-search-forward "\\(\\sw\\|\\s_\\)+") + (help-xref-button 0 'help-function-def sym file))) + (forward-line 1)) + (widen)) + (setq debugger-previous-backtrace (buffer-string))))) (defun debugger-step-through () "Proceed, stepping through subexpressions of this expression.