lisp/finder.el

   1 ;;; finder.el --- topic & keyword-based code finder
   2
   3 ;; Copyright (C) 1992, 1997-1999, 2001-2014 Free Software Foundation, Inc.
   4
   5 ;; Author: Eric S. Raymond <esr@snark.thyrsus.com>
   6 ;; Created: 16 Jun 1992
   7 ;; Version: 1.0
   8 ;; Keywords: help
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software: you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation, either version 3 of the License, or
  15 ;; (at your option) any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  24
  25 ;;; Commentary:
  26
  27 ;; This mode uses the Keywords library header to provide code-finding
  28 ;; services by keyword.
  29
  30 ;;; Code:
  31
  32 (require 'package)
  33 (require 'lisp-mnt)
  34 (require 'find-func) ;for find-library(-suffixes)
  35 (require 'finder-inf nil t)
  36
  37 ;; These are supposed to correspond to top-level customization groups,
  38 ;; says rms.
  39 (defvar finder-known-keywords
  40   '((abbrev     . "abbreviation handling, typing shortcuts, and macros")
  41     (bib        . "bibliography processors")
  42     (c          . "C and related programming languages")
  43     (calendar   . "calendar and time management tools")
  44     (comm       . "communications, networking, and remote file access")
  45     (convenience . "convenience features for faster editing")
  46     (data       . "editing data (non-text) files")
  47     (docs       . "Emacs documentation facilities")
  48     (emulations . "emulations of other editors")
  49     (extensions . "Emacs Lisp language extensions")
  50     (faces      . "fonts and colors for text")
  51     (files      . "file editing and manipulation")
  52     (frames     . "Emacs frames and window systems")
  53     (games      . "games, jokes and amusements")
  54     (hardware   . "interfacing with system hardware")
  55     (help       . "Emacs help systems")
  56     (hypermedia . "links between text or other media types")
  57     (i18n       . "internationalization and character-set support")
  58     (internal   . "code for Emacs internals, build process, defaults")
  59     (languages  . "specialized modes for editing programming languages")
  60     (lisp       . "Lisp support, including Emacs Lisp")
  61     (local      . "code local to your site")
  62     (maint      . "Emacs development tools and aids")
  63     (mail       . "email reading and posting")
  64     (matching   . "searching, matching, and sorting")
  65     (mouse      . "mouse support")
  66     (multimedia . "images and sound")
  67     (news       . "USENET news reading and posting")
  68     (outlines   . "hierarchical outlining and note taking")
  69     (processes  . "processes, subshells, and compilation")
  70     (terminals  . "text terminals (ttys)")
  71     (tex        . "the TeX document formatter")
  72     (tools      . "programming tools")
  73     (unix       . "UNIX feature interfaces and emulators")
  74     (vc         . "version control")
  75     (wp         . "word processing"))
  76   "Association list of the standard \"Keywords:\" headers.
  77 Each element has the form (KEYWORD . DESCRIPTION).")
  78
  79 (defvar finder-mode-map
  80   (let ((map (make-sparse-keymap))
  81         (menu-map (make-sparse-keymap "Finder")))
  82     (define-key map " " 'finder-select)
  83     (define-key map "f" 'finder-select)
  84     (define-key map [follow-link] 'mouse-face)
  85     (define-key map [mouse-2]   'finder-mouse-select)
  86     (define-key map "\C-m"      'finder-select)
  87     (define-key map "?" 'finder-summary)
  88     (define-key map "n" 'next-line)
  89     (define-key map "p" 'previous-line)
  90     (define-key map "q" 'finder-exit)
  91     (define-key map "d" 'finder-list-keywords)
  92
  93     (define-key map [menu-bar finder-mode]
  94       (cons "Finder" menu-map))
  95     (define-key menu-map [finder-exit]
  96       '(menu-item "Quit" finder-exit
  97                   :help "Exit Finder mode"))
  98     (define-key menu-map [finder-summary]
  99       '(menu-item "Summary" finder-summary
 100                   :help "Summary item on current line in a finder buffer"))
 101     (define-key menu-map [finder-list-keywords]
 102       '(menu-item "List keywords" finder-list-keywords
 103                   :help "Display descriptions of the keywords in the Finder buffer"))
 104     (define-key menu-map [finder-select]
 105       '(menu-item "Select" finder-select
 106                   :help "Select item on current line in a finder buffer"))
 107     map)
 108   "Keymap used in `finder-mode'.")
 109
 110 (defvar finder-mode-syntax-table
 111   (let ((st (make-syntax-table emacs-lisp-mode-syntax-table)))
 112     (modify-syntax-entry ?\; ".   " st)
 113     st)
 114   "Syntax table used while in `finder-mode'.")
 115
 116 (defvar finder-font-lock-keywords
 117   '(("`\\([^'`]+\\)'" 1 font-lock-constant-face prepend))
 118   "Font-lock keywords for Finder mode.")
 119
 120 (defvar finder-headmark nil
 121   "Internal Finder mode variable, local in Finder buffer.")
 122
 123 ;;; Code for regenerating the keyword list.
 124
 125 (defvar finder-keywords-hash nil
 126   "Hash table mapping keywords to lists of package names.
 127 Keywords and package names both should be symbols.")
 128
 129 (defvar generated-finder-keywords-file "finder-inf.el"
 130   "The function `finder-compile-keywords' writes keywords into this file.")
 131
 132 ;; Skip autogenerated files, because they will never contain anything
 133 ;; useful, and because in parallel builds of Emacs they may get
 134 ;; modified while we are trying to read them.
 135 ;; http://lists.gnu.org/archive/html/emacs-pretest-bug/2007-01/msg00469.html
 136 ;; ldefs-boot is not auto-generated, but has nothing useful.
 137 (defvar finder-no-scan-regexp "\\(^\\.#\\|\\(loaddefs\\|ldefs-boot\\|\
 138 cus-load\\|finder-inf\\|esh-groups\\|subdirs\\|leim-list\\)\\.el$\\)"
 139   "Regexp matching file names not to scan for keywords.")
 140
 141 (autoload 'autoload-rubric "autoload")
 142
 143 (defconst finder--builtins-descriptions
 144   ;; I have no idea whether these are supposed to be capitalized
 145   ;; and/or end in a full-stop.  Existing file headers are inconsistent,
 146   ;; but mainly seem to not do so.
 147   '((emacs . "the extensible text editor")
 148     (nxml . "a new XML mode"))
 149   "Alist of built-in package descriptions.
 150 Entries have the form (PACKAGE-SYMBOL . DESCRIPTION).
 151 When generating `package--builtins', this overrides what the description
 152 would otherwise be.")
 153
 154 (defvar finder--builtins-alist
 155   '(("calc" . calc)
 156     ("ede"  . ede)
 157     ("erc"  . erc)
 158     ("eshell" . eshell)
 159     ("gnus" . gnus)
 160     ("international" . emacs)
 161     ("language" . emacs)
 162     ("mh-e" . mh-e)
 163     ("semantic" . semantic)
 164     ("analyze" . semantic)
 165     ("bovine" . semantic)
 166     ("decorate" . semantic)
 167     ("symref" . semantic)
 168     ("wisent" . semantic)
 169     ;; This should really be ("nxml" . nxml-mode), because nxml-mode.el
 170     ;; is the main file for the package.  Then we would not need an
 171     ;; entry in finder--builtins-descriptions.  But I do not know if
 172     ;; it is safe to change this, in case it is already in use.
 173     ("nxml" . nxml)
 174     ("org"  . org)
 175     ("srecode" . srecode)
 176     ("term" . emacs)
 177     ("url"  . url))
 178   "Alist of built-in package directories.
 179 Each element should have the form (DIR . PACKAGE), where DIR is a
 180 directory name and PACKAGE is the name of a package (a symbol).
 181 When generating `package--builtins', Emacs assumes any file in
 182 DIR is part of the package PACKAGE.")
 183
 184 (defun finder-compile-keywords (&rest dirs)
 185   "Regenerate list of built-in Emacs packages.
 186 This recomputes `package--builtins' and `finder-keywords-hash',
 187 and prints them into the file `generated-finder-keywords-file'.
 188
 189 Optional DIRS is a list of Emacs Lisp directories to compile
 190 from; the default is `load-path'."
 191   ;; Allow compressed files also.
 192   (setq package--builtins nil)
 193   (setq finder-keywords-hash (make-hash-table :test 'eq))
 194   (let ((el-file-regexp "^\\([^=].*\\)\\.el\\(\\.\\(gz\\|Z\\)\\)?$")
 195         package-override files base-name ; processed
 196         summary keywords package version entry desc)
 197     (dolist (d (or dirs load-path))
 198       (when (file-exists-p (directory-file-name d))
 199         (message "Directory %s" d)
 200         (setq package-override
 201               (intern-soft
 202                (cdr-safe
 203                 (assoc (file-name-nondirectory (directory-file-name d))
 204                        finder--builtins-alist))))
 205         (setq files (directory-files d nil el-file-regexp))
 206         (dolist (f files)
 207           (unless (or (string-match finder-no-scan-regexp f)
 208                       (null (setq base-name
 209                                   (and (string-match el-file-regexp f)
 210                                        (intern (match-string 1 f))))))
 211 ;;                    (memq base-name processed))
 212 ;; There are multiple files in the tree with the same basename.
 213 ;; So skipping files based on basename means you randomly (depending
 214 ;; on which order the files are traversed in) miss some packages.
 215 ;; http://debbugs.gnu.org/14010
 216 ;; You might think this could lead to two files providing the same package,
 217 ;; but it does not, because the duplicates are (at time of writing)
 218 ;; all due to files in cedet, which end up with package-override set.
 219 ;; FIXME this is obviously fragile.
 220 ;; Make the (eq base-name package) case below issue a warning if
 221 ;; package-override is nil?
 222 ;;          (push base-name processed)
 223             (with-temp-buffer
 224               (insert-file-contents (expand-file-name f d))
 225               (setq keywords (mapcar 'intern (lm-keywords-list))
 226                     package  (or package-override
 227                                  (let ((str (lm-header "package")))
 228                                    (if str (intern str)))
 229                                  base-name)
 230                     summary  (or (cdr
 231                                   (assq package finder--builtins-descriptions))
 232                                  (lm-synopsis))
 233                     version  (lm-header "version")))
 234             (when summary
 235               (setq version (ignore-errors (version-to-list version)))
 236               (setq entry (assq package package--builtins))
 237               (cond ((null entry)
 238                      (push (cons package
 239                                  (package-make-builtin version summary))
 240                            package--builtins))
 241                     ;; The idea here is that eg calc.el gets to define
 242                     ;; the description of the calc package.
 243                     ;; This does not work for eg nxml-mode.el.
 244                     ((eq base-name package)
 245                      (setq desc (cdr entry))
 246                      (aset desc 0 version)
 247                      (aset desc 2 summary)))
 248               (dolist (kw keywords)
 249                 (puthash kw
 250                          (cons package
 251                                (delq package
 252                                      (gethash kw finder-keywords-hash)))
 253                          finder-keywords-hash))))))))
 254
 255   (setq package--builtins
 256         (sort package--builtins
 257               (lambda (a b) (string< (symbol-name (car a))
 258                                      (symbol-name (car b))))))
 259
 260   (with-current-buffer
 261       (find-file-noselect generated-finder-keywords-file)
 262     (setq buffer-undo-list t)
 263     (erase-buffer)
 264     (insert (autoload-rubric generated-finder-keywords-file
 265                              "keyword-to-package mapping" t))
 266     (search-backward "\f")
 267     ;; FIXME: Now that we have package--builtin-versions, package--builtins is
 268     ;; only needed to get the list of unversioned packages and to get the
 269     ;; summary description of each package.
 270     (insert "(setq package--builtins '(\n")
 271     (dolist (package package--builtins)
 272       (insert "  ")
 273       (prin1 package (current-buffer))
 274       (insert "\n"))
 275     (insert "))\n\n")
 276     ;; Insert hash table.
 277     (insert "(setq finder-keywords-hash\n      ")
 278     (prin1 finder-keywords-hash (current-buffer))
 279     (insert ")\n")
 280     (basic-save-buffer)))
 281
 282 (defun finder-compile-keywords-make-dist ()
 283   "Regenerate `finder-inf.el' for the Emacs distribution."
 284   (apply 'finder-compile-keywords command-line-args-left)
 285   (kill-emacs))
 286
 287 ;;; Now the retrieval code
 288
 289 (defun finder-insert-at-column (column &rest strings)
 290   "Insert, at column COLUMN, other args STRINGS."
 291   (if (>= (current-column) column) (insert "\n"))
 292   (move-to-column column t)
 293   (apply 'insert strings))
 294
 295 (defvar finder-help-echo nil)
 296
 297 (defun finder-mouse-face-on-line ()
 298   "Put `mouse-face' and `help-echo' properties on the previous line."
 299   (save-excursion
 300     (forward-line -1)
 301     ;; If finder-insert-at-column moved us to a new line, go back one more.
 302     (if (looking-at "[ \t]") (forward-line -1))
 303     (unless finder-help-echo
 304       (setq finder-help-echo
 305             (let* ((keys1 (where-is-internal 'finder-select
 306                                              finder-mode-map))
 307                    (keys (nconc (where-is-internal
 308                                  'finder-mouse-select finder-mode-map)
 309                                 keys1)))
 310               (concat (mapconcat 'key-description keys ", ")
 311                       ": select item"))))
 312     (add-text-properties
 313      (line-beginning-position) (line-end-position)
 314      '(mouse-face highlight
 315                   help-echo finder-help-echo))))
 316
 317 (defun finder-unknown-keywords ()
 318   "Return an alist of unknown keywords and number of their occurrences.
 319 Unknown keywords are those present in `finder-keywords-hash' but
 320 not `finder-known-keywords'."
 321   (let (alist)
 322     (maphash (lambda (kw packages)
 323                (unless (assq kw finder-known-keywords)
 324                  (push (cons kw (length packages)) alist)))
 325              finder-keywords-hash)
 326     (sort alist (lambda (a b) (string< (car a) (car b))))))
 327
 328 ;;;###autoload
 329 (defun finder-list-keywords ()
 330   "Display descriptions of the keywords in the Finder buffer."
 331   (interactive)
 332   (if (get-buffer "*Finder*")
 333       (pop-to-buffer "*Finder*")
 334     (pop-to-buffer (get-buffer-create "*Finder*"))
 335     (finder-mode)
 336     (let ((inhibit-read-only t))
 337       (erase-buffer)
 338       (dolist (assoc finder-known-keywords)
 339         (let ((keyword (car assoc)))
 340           (insert (propertize (symbol-name keyword)
 341                               'font-lock-face 'font-lock-constant-face))
 342           (finder-insert-at-column 14 (concat (cdr assoc) "\n"))
 343           (finder-mouse-face-on-line)))
 344       (goto-char (point-min))
 345       (setq finder-headmark (point)
 346             buffer-read-only t)
 347       (set-buffer-modified-p nil)
 348       (balance-windows)
 349       (finder-summary))))
 350
 351 (defun finder-list-matches (key)
 352   (let* ((id (intern key))
 353          (packages (gethash id finder-keywords-hash)))
 354     (unless packages
 355       (error "No packages matching key `%s'" key))
 356     (let ((package-list-unversioned t))
 357       (package-show-package-list packages))))
 358
 359 (define-button-type 'finder-xref 'action #'finder-goto-xref)
 360
 361 (defun finder-goto-xref (button)
 362   "Jump to a lisp file for the BUTTON at point."
 363   (let* ((file (button-get button 'xref))
 364          (lib (locate-library file)))
 365     (if lib (finder-commentary lib)
 366       (message "Unable to locate `%s'" file))))
 367
 368 ;;;###autoload
 369 (defun finder-commentary (file)
 370   "Display FILE's commentary section.
 371 FILE should be in a form suitable for passing to `locate-library'."
 372   (interactive
 373    (list
 374     (completing-read "Library name: "
 375                      (apply-partially 'locate-file-completion-table
 376                                       (or find-function-source-path load-path)
 377                                       (find-library-suffixes)))))
 378   (let ((str (lm-commentary (find-library-name file))))
 379     (or str (error "Can't find any Commentary section"))
 380     ;; This used to use *Finder* but that would clobber the
 381     ;; directory of categories.
 382     (pop-to-buffer "*Finder-package*")
 383     (setq buffer-read-only nil
 384           buffer-undo-list t)
 385     (erase-buffer)
 386     (insert str)
 387     (goto-char (point-min))
 388     (delete-blank-lines)
 389     (goto-char (point-max))
 390     (delete-blank-lines)
 391     (goto-char (point-min))
 392     (while (re-search-forward "^;+ ?" nil t)
 393       (replace-match "" nil nil))
 394     (goto-char (point-min))
 395     (while (re-search-forward "\\<\\([-[:alnum:]]+\\.el\\)\\>" nil t)
 396       (if (locate-library (match-string 1))
 397           (make-text-button (match-beginning 1) (match-end 1)
 398                             'xref (match-string-no-properties 1)
 399                             'help-echo "Read this file's commentary"
 400                             :type 'finder-xref)))
 401     (goto-char (point-min))
 402     (setq buffer-read-only t)
 403     (set-buffer-modified-p nil)
 404     (shrink-window-if-larger-than-buffer)
 405     (finder-mode)
 406     (finder-summary)))
 407
 408 (defun finder-current-item ()
 409   (let ((key (save-excursion
 410                (beginning-of-line)
 411                (current-word))))
 412     (if (or (and finder-headmark (< (point) finder-headmark))
 413             (zerop (length key)))
 414         (error "No keyword or filename on this line")
 415       key)))
 416
 417 (defun finder-select ()
 418   "Select item on current line in a Finder buffer."
 419   (interactive)
 420   (let ((key (finder-current-item)))
 421       (if (string-match "\\.el$" key)
 422           (finder-commentary key)
 423         (finder-list-matches key))))
 424
 425 (defun finder-mouse-select (event)
 426   "Select item in a Finder buffer with the mouse."
 427   (interactive "e")
 428   (with-current-buffer (window-buffer (posn-window (event-start event)))
 429     (goto-char (posn-point (event-start event)))
 430     (finder-select)))
 431
 432 ;;;###autoload
 433 (defun finder-by-keyword ()
 434   "Find packages matching a given keyword."
 435   (interactive)
 436   (finder-list-keywords))
 437
 438 (define-derived-mode finder-mode nil "Finder"
 439   "Major mode for browsing package documentation.
 440 \\<finder-mode-map>
 441 \\[finder-select]       more help for the item on the current line
 442 \\[finder-exit] exit Finder mode and kill the Finder buffer."
 443   :syntax-table finder-mode-syntax-table
 444   (setq buffer-read-only t
 445         buffer-undo-list t)
 446   (set (make-local-variable 'finder-headmark) nil))
 447
 448 (defun finder-summary ()
 449   "Summarize basic Finder commands."
 450   (interactive)
 451   (message "%s"
 452    (substitute-command-keys
 453     "\\<finder-mode-map>\\[finder-select] = select, \
 454 \\[finder-mouse-select] = select, \\[finder-list-keywords] = to \
 455 finder directory, \\[finder-exit] = quit, \\[finder-summary] = help")))
 456
 457 (defun finder-exit ()
 458   "Exit Finder mode.
 459 Delete the window and kill all Finder-related buffers."
 460   (interactive)
 461   (ignore-errors (delete-window))
 462   (let ((buf "*Finder*"))
 463     (and (get-buffer buf) (kill-buffer buf))))
 464
 465 (defun finder-unload-function ()
 466   "Unload the Finder library."
 467   (with-demoted-errors (unload-feature 'finder-inf t))
 468   ;; continue standard unloading
 469   nil)
 470
 471 \f
 472 (provide 'finder)
 473
 474 ;;; finder.el ends here