lisp/isearch-multi.el

   1 ;;; isearch-multi.el --- isearch extensions for multi-buffer search
   2
   3 ;; Copyright (C) 2007, 2008  Free Software Foundation, Inc.
   4
   5 ;; Author: Juri Linkov <juri@jurta.org>
   6 ;; Keywords: matching
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;; This file adds more dimensions to the search space.  It implements
  26 ;; various features that extend isearch.  One of them is an ability to
  27 ;; search through multiple buffers.
  28
  29 ;;; Code:
  30
  31 ;;; Search multiple buffers
  32
  33 (defgroup isearch-buffers nil
  34   "Using isearch to search through multiple buffers."
  35   :version "23.1"
  36   :group 'isearch)
  37
  38 (defcustom isearch-buffers-multi t
  39   "Non-nil enables searching multiple related buffers, in certain modes."
  40   :type 'boolean
  41   :version "23.1"
  42   :group 'isearch-buffers)
  43
  44 (defcustom isearch-buffers-pause t
  45   "A choice defining where to pause the search.
  46 If the value is nil, don't pause before going to the next buffer.
  47 If the value is `initial', pause only after a failing search in the
  48 initial buffer.
  49 If t, pause in all buffers that contain the search string."
  50   :type '(choice
  51           (const :tag "Don't pause" nil)
  52           (const :tag "Only in initial buffer" initial)
  53           (const :tag "All buffers" t))
  54   :version "23.1"
  55   :group 'isearch-buffers)
  56
  57 ;;;###autoload
  58 (defvar isearch-buffers-current-buffer nil
  59   "The buffer where the search is currently searching.
  60 The value is nil when the search still is in the initial buffer.")
  61
  62 ;;;###autoload
  63 (defvar isearch-buffers-next-buffer-function nil
  64   "Function to call to get the next buffer to search.
  65
  66 When this variable is set to a function that returns a buffer, then
  67 after typing another \\[isearch-forward] or \\[isearch-backward] \
  68 at a failing search, the search goes
  69 to the next buffer in the series and continues searching for the
  70 next occurrence.
  71
  72 The first argument of this function is the current buffer where the
  73 search is currently searching.  It defines the base buffer relative to
  74 which this function should find the next buffer.  When the isearch
  75 direction is backward (when `isearch-forward' is nil), this function
  76 should return the previous buffer to search.  If the second argument of
  77 this function WRAP is non-nil, then it should return the first buffer
  78 in the series; and for the backward search, it should return the last
  79 buffer in the series.")
  80
  81 ;;;###autoload
  82 (define-minor-mode isearch-buffers-minor-mode
  83   "Minor mode for using isearch to search through multiple buffers.
  84 With arg, turn isearch-buffers minor mode on if arg is positive, off otherwise."
  85   :group 'isearch-buffers ;; :lighter " X"
  86   (if isearch-buffers-minor-mode
  87       (progn
  88         (add-hook 'isearch-mode-hook 'isearch-buffers-init nil t)
  89         (set (make-local-variable 'isearch-search-fun-function)
  90              'isearch-buffers-search-fun)
  91         (set (make-local-variable 'isearch-wrap-function)
  92              'isearch-buffers-wrap)
  93         (set (make-local-variable 'isearch-push-state-function)
  94              'isearch-buffers-push-state))
  95     (remove-hook 'isearch-mode-hook 'isearch-buffers-init t)
  96     (kill-local-variable 'isearch-search-fun-function)
  97     (kill-local-variable 'isearch-wrap-function)
  98     (kill-local-variable 'isearch-push-state-function)))
  99
 100 (defun isearch-buffers-init ()
 101   "Set up isearch to search multiple buffers.
 102 Intended to be added to `isearch-mode-hook'."
 103   (setq isearch-buffers-current-buffer nil))
 104
 105 (defun isearch-buffers-search-fun ()
 106   "Return the proper search function, for isearch in multiple buffers."
 107   (lambda (string bound noerror)
 108     (let ((search-fun
 109            ;; Use standard functions to search within one buffer
 110            (cond
 111             (isearch-word
 112              (if isearch-forward 'word-search-forward 'word-search-backward))
 113             (isearch-regexp
 114              (if isearch-forward 're-search-forward 're-search-backward))
 115             (t
 116              (if isearch-forward 'search-forward 'search-backward))))
 117           found buffer)
 118       (or
 119        ;; 1. First try searching in the initial buffer
 120        (let ((res (funcall search-fun string bound noerror)))
 121          ;; Reset wrapping for all-buffers pause after successful search
 122          (if (and res (eq isearch-buffers-pause t))
 123              (setq isearch-buffers-current-buffer nil))
 124          res)
 125        ;; 2. If the above search fails, start visiting next/prev buffers
 126        ;; successively, and search the string in them.  Do this only
 127        ;; when bound is nil (i.e. not while lazy-highlighting search
 128        ;; strings in the current buffer).
 129        (when (and (not bound) isearch-buffers-multi)
 130          ;; If no-pause or there was one attempt to leave the current buffer
 131          (if (or (null isearch-buffers-pause)
 132                  (and isearch-buffers-pause isearch-buffers-current-buffer))
 133              (condition-case nil
 134                  (progn
 135                    (while (not found)
 136                      ;; Find the next buffer to search
 137                      (setq buffer (funcall isearch-buffers-next-buffer-function
 138                                            buffer))
 139                      (with-current-buffer buffer
 140                        (goto-char (if isearch-forward (point-min) (point-max)))
 141                        (setq isearch-barrier (point) isearch-opoint (point))
 142                        ;; After visiting the next/prev buffer search the
 143                        ;; string in it again, until the function in
 144                        ;; isearch-buffers-next-buffer-function raises an error
 145                        ;; at the beginning/end of the buffer sequence.
 146                        (setq found (funcall search-fun string bound noerror))))
 147                    ;; Set buffer for isearch-search-string to switch
 148                    (if buffer (setq isearch-buffers-current-buffer buffer))
 149                    ;; Return point of the new search result
 150                    found)
 151                ;; Return nil when isearch-buffers-next-buffer-function fails
 152                (error nil))
 153            (signal 'search-failed (list string "Repeat for next buffer"))))))))
 154
 155 (defun isearch-buffers-wrap ()
 156   "Wrap the multiple buffers search when search is failed.
 157 Switch buffer to the first buffer for a forward search,
 158 or to the last buffer for a backward search.
 159 Set `isearch-buffers-current-buffer' to the current buffer to display
 160 the isearch suffix message [initial buffer] only when isearch leaves
 161 the initial buffer."
 162   (if (or (null isearch-buffers-pause)
 163           (and isearch-buffers-pause isearch-buffers-current-buffer))
 164       (progn
 165         (switch-to-buffer
 166          (setq isearch-buffers-current-buffer
 167                (funcall isearch-buffers-next-buffer-function
 168                         (current-buffer) t)))
 169         (goto-char (if isearch-forward (point-min) (point-max))))
 170     (setq isearch-buffers-current-buffer (current-buffer))
 171     (setq isearch-wrapped nil)))
 172
 173 (defun isearch-buffers-push-state ()
 174   "Save a function restoring the state of multiple buffers search.
 175 Save the current buffer to the additional state parameter in the
 176 search status stack."
 177   `(lambda (cmd)
 178      (isearch-buffers-pop-state cmd ,(current-buffer))))
 179
 180 (defun isearch-buffers-pop-state (cmd buffer)
 181   "Restore the multiple buffers search state.
 182 Switch to the buffer restored from the search status stack."
 183   (unless (equal buffer (current-buffer))
 184     (switch-to-buffer (setq isearch-buffers-current-buffer buffer))))
 185
 186 (provide 'isearch-multi)
 187
 188 ;; arch-tag: a6d38ffa-4d14-4e39-8ac6-46af9d6a6773
 189 ;;; isearch-multi.el ends here