lisp/emacs-lisp/check-declare.el

   1 ;;; check-declare.el --- Check declare-function statements
   2
   3 ;; Copyright (C) 2007, 2008, 2009, 2010, 2011  Free Software Foundation, Inc.
   4
   5 ;; Author: Glenn Morris <rgm@gnu.org>
   6 ;; Keywords: lisp, tools, maint
   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 ;; The byte-compiler often warns about undefined functions that you
  26 ;; know will actually be defined when it matters.  The `declare-function'
  27 ;; statement allows you to suppress these warnings.  This package
  28 ;; checks that all such statements in a file or directory are accurate.
  29 ;; The entry points are `check-declare-file' and `check-declare-directory'.
  30
  31 ;; For more information, see Info node `elisp(Declaring Functions)'.
  32
  33 ;;; TODO:
  34
  35 ;; 1. Warn about functions marked as obsolete, eg
  36 ;; password-read-and-add in smime.el.
  37 ;; 2. defmethod, defclass argument checking.
  38 ;; 3. defclass also defines -p and -child-p.
  39
  40 ;;; Code:
  41
  42 (defconst check-declare-warning-buffer "*Check Declarations Warnings*"
  43   "Name of buffer used to display any `check-declare' warnings.")
  44
  45 (defun check-declare-locate (file basefile)
  46   "Return the full path of FILE.
  47 Expands files with a \".c\" or \".m\" extension relative to the Emacs
  48 \"src/\" directory.  Otherwise, `locate-library' searches for FILE.
  49 If that fails, expands FILE relative to BASEFILE's directory part.
  50 The returned file might not exist.  If FILE has an \"ext:\" prefix, so does
  51 the result."
  52   (let ((ext (string-match "^ext:" file))
  53         tfile)
  54     (if ext
  55         (setq file (substring file 4)))
  56     (setq file
  57           (if (member (file-name-extension file) '("c" "m"))
  58               (expand-file-name file (expand-file-name "src" source-directory))
  59             (if (setq tfile (locate-library file))
  60                 (progn
  61                   (setq tfile
  62                         (replace-regexp-in-string "\\.elc\\'" ".el" tfile))
  63                   (if (and (not (file-exists-p tfile))
  64                            (file-exists-p (concat tfile ".gz")))
  65                       (concat tfile ".gz")
  66                     tfile))
  67               (setq tfile (expand-file-name file
  68                                             (file-name-directory basefile)))
  69               (if (or (file-exists-p tfile)
  70                       (string-match "\\.el\\'" tfile))
  71                   tfile
  72                 (concat tfile ".el")))))
  73     (if ext (concat "ext:" file)
  74       file)))
  75
  76 (defun check-declare-scan (file)
  77   "Scan FILE for `declare-function' calls.
  78 Return a list with elements of the form (FNFILE FN ARGLIST FILEONLY),
  79 where only the first two elements need be present.  This claims that FNFILE
  80 defines FN, with ARGLIST.  FILEONLY non-nil means only check that FNFILE
  81 exists, not that it defines FN.  This is for function definitions that we
  82 don't know how to recognize (e.g. some macros)."
  83   (let ((m (format "Scanning %s..." file))
  84         alist form len fn fnfile arglist fileonly)
  85     (message "%s" m)
  86     (with-temp-buffer
  87       (insert-file-contents file)
  88       ;; FIXME we could theoretically be inside a string.
  89       (while (re-search-forward "^[ \t]*\\((declare-function\\)[ \t\n]" nil t)
  90         (goto-char (match-beginning 1))
  91         (if (and (setq form (ignore-errors (read (current-buffer)))
  92                        len (length form))
  93                  (> len 2) (< len 6)
  94                  (symbolp (setq fn (cadr form)))
  95                  (setq fn (symbol-name fn)) ; later we use as a search string
  96                  (stringp (setq fnfile (nth 2 form)))
  97                  (setq fnfile (check-declare-locate fnfile
  98                                                     (expand-file-name file)))
  99                  ;; Use `t' to distinguish unspecified arglist from empty one.
 100                  (or (eq t (setq arglist (if (> len 3)
 101                                              (nth 3 form)
 102                                            t)))
 103                      (listp arglist))
 104                  (symbolp (setq fileonly (nth 4 form))))
 105             (setq alist (cons (list fnfile fn arglist fileonly) alist))
 106           ;; FIXME make this more noticeable.
 107           (message "Malformed declaration for `%s'" (cadr form)))))
 108     (message "%sdone" m)
 109     alist))
 110
 111 (defun check-declare-errmsg (errlist &optional full)
 112   "Return a string with the number of errors in ERRLIST, if any.
 113 Normally just counts the number of elements in ERRLIST.
 114 With optional argument FULL, sums the number of elements in each element."
 115   (if errlist
 116       (let ((l (length errlist)))
 117         (when full
 118           (setq l 0)
 119           (dolist (e errlist)
 120             (setq l (+ l (1- (length e))))))
 121         (format "%d problem%s found" l (if (= l 1) "" "s")))
 122     "OK"))
 123
 124 (autoload 'byte-compile-arglist-signature "bytecomp")
 125
 126 (defun check-declare-verify (fnfile fnlist)
 127   "Check that FNFILE contains function definitions matching FNLIST.
 128 Each element of FNLIST has the form (FILE FN ARGLIST FILEONLY), where
 129 only the first two elements need be present.  This means FILE claimed FN
 130 was defined in FNFILE with the specified ARGLIST.  FILEONLY non-nil means
 131 to only check that FNFILE exists, not that it actually defines FN.
 132
 133 Returns nil if all claims are found to be true, otherwise a list
 134 of errors with elements of the form \(FILE FN TYPE), where TYPE
 135 is a string giving details of the error."
 136   (let ((m (format "Checking %s..." fnfile))
 137         (cflag (member (file-name-extension fnfile) '("c" "m")))
 138         (ext (string-match "^ext:" fnfile))
 139         re fn sig siglist arglist type errlist minargs maxargs)
 140     (message "%s" m)
 141     (if ext
 142         (setq fnfile (substring fnfile 4)))
 143     (if (file-regular-p fnfile)
 144         (with-temp-buffer
 145           (insert-file-contents fnfile)
 146           ;; defsubst's don't _have_ to be known at compile time.
 147           (setq re (format (if cflag
 148                                "^[ \t]*\\(DEFUN\\)[ \t]*([ \t]*\"%s\""
 149                              "^[ \t]*(\\(fset[ \t]+'\\|\
 150 def\\(?:un\\|subst\\|foo\\|method\\|class\\|\
 151 ine-\\(?:derived\\|generic\\|\\(?:global\\(?:ized\\)?-\\)?minor\\)-mode\\|\
 152 \\(?:ine-obsolete-function-\\)?alias[ \t]+'\\|\
 153 ine-overloadable-function\\)\\)\
 154 \[ \t]*%s\\([ \t;]+\\|$\\)")
 155                            (regexp-opt (mapcar 'cadr fnlist) t)))
 156           (while (re-search-forward re nil t)
 157             (skip-chars-forward " \t\n")
 158             (setq fn (match-string 2)
 159                   type (match-string 1)
 160                   ;; (min . max) for a fixed number of arguments, or
 161                   ;; arglists with optional elements.
 162                   ;; (min) for arglists with &rest.
 163                   ;; sig = 'err means we could not find an arglist.
 164                   sig (cond (cflag
 165                              (or
 166                               (when (search-forward "," nil t 3)
 167                                 (skip-chars-forward " \t\n")
 168                                 ;; Assuming minargs and maxargs on same line.
 169                                 (when (looking-at "\\([0-9]+\\)[ \t]*,[ \t]*\
 170 \\([0-9]+\\|MANY\\|UNEVALLED\\)")
 171                                   (setq minargs (string-to-number
 172                                                  (match-string 1))
 173                                         maxargs (match-string 2))
 174                                   (cons minargs (unless (string-match "[^0-9]"
 175                                                                       maxargs)
 176                                                  (string-to-number
 177                                                   maxargs)))))
 178                               'err))
 179                             ((string-match
 180                               "\\`define-\\(derived\\|generic\\)-mode\\'"
 181                               type)
 182                              '(0 . 0))
 183                             ((string-match
 184                               "\\`define\\(-global\\(ized\\)?\\)?-minor-mode\\'"
 185                               type)
 186                              '(0 . 1))
 187                             ;; Prompt to update.
 188                             ((string-match
 189                               "\\`define-obsolete-function-alias\\>"
 190                               type)
 191                              'obsolete)
 192                             ;; Can't easily check arguments in these cases.
 193                             ((string-match "\\`\\(def\\(alias\\|\
 194 method\\|class\\)\\|fset\\)\\>" type)
 195                              t)
 196                             ((looking-at "\\((\\|nil\\)")
 197                              (byte-compile-arglist-signature
 198                               (read (current-buffer))))
 199                             (t
 200                              'err))
 201                   ;; alist of functions and arglist signatures.
 202                   siglist (cons (cons fn sig) siglist)))))
 203     (dolist (e fnlist)
 204       (setq arglist (nth 2 e)
 205             type
 206             (if (not re)
 207                 "file not found"
 208               (if (not (setq sig (assoc (cadr e) siglist)))
 209                   (unless (nth 3 e)     ; fileonly
 210                     "function not found")
 211                 (setq sig (cdr sig))
 212                 (cond ((eq sig 'obsolete) ; check even when no arglist specified
 213                        "obsolete alias")
 214                       ;; arglist t means no arglist specified, as
 215                       ;; opposed to an empty arglist.
 216                       ((eq arglist t) nil)
 217                       ((eq sig t) nil) ; eg defalias - can't check arguments
 218                       ((eq sig 'err)
 219                        "arglist not found") ; internal error
 220                       ((not (equal (byte-compile-arglist-signature
 221                                     arglist)
 222                                    sig))
 223                        "arglist mismatch")))))
 224       (when type
 225         (setq errlist (cons (list (car e) (cadr e) type) errlist))))
 226     (message "%s%s" m
 227              (if (or re (not ext))
 228                  (check-declare-errmsg errlist)
 229                (progn
 230                  (setq errlist nil)
 231                  "skipping external file")))
 232     errlist))
 233
 234 (defun check-declare-sort (alist)
 235   "Sort a list with elements FILE (FNFILE ...).
 236 Returned list has elements FNFILE (FILE ...)."
 237   (let (file fnfile rest sort a)
 238     (dolist (e alist)
 239       (setq file (car e))
 240       (dolist (f (cdr e))
 241         (setq fnfile (car f)
 242               rest (cdr f))
 243         (if (setq a (assoc fnfile sort))
 244             (setcdr a (append (cdr a) (list (cons file rest))))
 245           (setq sort (cons (list fnfile (cons file rest)) sort)))))
 246     sort))
 247
 248 (defun check-declare-warn (file fn fnfile type)
 249   "Warn that FILE made a false claim about FN in FNFILE.
 250 TYPE is a string giving the nature of the error.  Warning is displayed in
 251 `check-declare-warning-buffer'."
 252   (display-warning 'check-declare
 253                    (format "%s said `%s' was defined in %s: %s"
 254                            (file-name-nondirectory file) fn
 255                            (file-name-nondirectory fnfile)
 256                            type)
 257                    nil check-declare-warning-buffer))
 258
 259 (defun check-declare-files (&rest files)
 260   "Check veracity of all `declare-function' statements in FILES.
 261 Return a list of any errors found."
 262   (let (alist err errlist)
 263     (dolist (file files)
 264       (setq alist (cons (cons file (check-declare-scan file)) alist)))
 265     ;; Sort so that things are ordered by the files supposed to
 266     ;; contain the defuns.
 267     (dolist (e (check-declare-sort alist))
 268       (if (setq err (check-declare-verify (car e) (cdr e)))
 269           (setq errlist (cons (cons (car e) err) errlist))))
 270     (if (get-buffer check-declare-warning-buffer)
 271         (kill-buffer check-declare-warning-buffer))
 272     ;; Sort back again so that errors are ordered by the files
 273     ;; containing the declare-function statements.
 274     (dolist (e (check-declare-sort errlist))
 275         (dolist (f (cdr e))
 276           (check-declare-warn (car e) (cadr f) (car f) (nth 2 f))))
 277     errlist))
 278
 279 ;;;###autoload
 280 (defun check-declare-file (file)
 281   "Check veracity of all `declare-function' statements in FILE.
 282 See `check-declare-directory' for more information."
 283   (interactive "fFile to check: ")
 284   (or (file-exists-p file)
 285       (error "File `%s' not found" file))
 286   (let ((m (format "Checking %s..." file))
 287         errlist)
 288     (message "%s" m)
 289     (setq errlist (check-declare-files file))
 290     (message "%s%s" m (check-declare-errmsg errlist))
 291     errlist))
 292
 293 ;;;###autoload
 294 (defun check-declare-directory (root)
 295   "Check veracity of all `declare-function' statements under directory ROOT.
 296 Returns non-nil if any false statements are found."
 297   (interactive "DDirectory to check: ")
 298   (or (file-directory-p (setq root (expand-file-name root)))
 299       (error "Directory `%s' not found" root))
 300   (let ((m "Checking `declare-function' statements...")
 301         (m2 "Finding files with declarations...")
 302         errlist files)
 303     (message "%s" m)
 304     (message "%s" m2)
 305     (setq files (process-lines find-program root
 306                                "-name" "*.el"
 307                                "-exec" grep-program
 308                                "-l" "^[ \t]*(declare-function" "{}" ";"))
 309     (message "%s%d found" m2 (length files))
 310     (when files
 311       (setq errlist (apply 'check-declare-files files))
 312       (message "%s%s" m (check-declare-errmsg errlist t))
 313       errlist)))
 314
 315 (provide 'check-declare)
 316
 317 ;;; check-declare.el ends here.