test/biditest.el

   1 ;;; biditest.el --- test bidi reordering in GNU Emacs display engine.
   2
   3 ;; Copyright (C) 2013-2014 Free Software Foundation, Inc.
   4
   5 ;; Author: Eli Zaretskii
   6 ;; Maintainer: emacs-devel@gnu.org
   7 ;; Package: emacs
   8
   9 ;; This program is free software: you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation, either version 3 of the License, or
  12 ;; (at your option) any later version.
  13
  14 ;; This program is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  21
  22 ;;; Commentary:
  23
  24 ;; Produce a specially-formatted text file from BidiCharacterTest.txt
  25 ;; file that is part of the Unicode Standard's UCD package.  The file
  26 ;; shows the expected results of reordering according to the UBA.  The
  27 ;; file is supposed to be visited in Emacs, and the resulting display
  28 ;; compared with the expected one.
  29
  30 ;;; Code:
  31
  32 (defun biditest-generate-testfile (input-file output-file)
  33   "Generate a bidi test file OUTPUT-FILE from data in INPUT-FILE.
  34
  35 INPUT-FILE should be in the format of the BidiCharacterTest.txt file
  36 available from the Unicode site, as part of the UCD database, see
  37 http://www.unicode.org/Public/UCD/latest/ucd/BidiCharacterTest.txt.
  38
  39 The resulting file should be viewed with `inhibit-bidi-mirroring' set to t."
  40   (let ((output-buf (get-buffer-create "*biditest-output*"))
  41         (lnum 1)
  42         tbuf)
  43     (with-temp-buffer
  44       (message "Generating output in %s ..." output-file)
  45       (setq tbuf (current-buffer))
  46       (insert-file-contents input-file)
  47       (goto-char (point-min))
  48       (while (not (eobp))
  49         (when (looking-at "^\\([0-9A-F ]+\\);\\([012]\\);\\([01]\\);\\([0-9 ]+\\);\\([0-9 ]+\\)$")
  50           (let ((codes (match-string 1))
  51                 (default-paragraph (match-string 2))
  52                 (resolved-paragraph (match-string 3))
  53                 ;; FIXME: Should compare LEVELS with what the display
  54                 ;; engine actually produced.
  55                 (levels (match-string 4))
  56                 (indices (match-string 5)))
  57             (setq codes (split-string codes " ")
  58                   indices (split-string indices " "))
  59             (switch-to-buffer output-buf)
  60             (insert (format "Test on line %d:\n\n" lnum))
  61             ;; Force paragraph direction to what the UCD test
  62             ;; specifies.
  63             (insert (cond
  64                      ((string= default-paragraph "0") ;L2R
  65                       #x200e)
  66                      ((string= default-paragraph "1") ;R2L
  67                       #x200f)
  68                      (t "")))   ; dynamic
  69             ;; Insert the characters
  70             (mapc (lambda (code)
  71                     (insert (string-to-number code 16)))
  72                   codes)
  73             (insert "\n\n")
  74             ;; Insert the expected results
  75             (insert "Expected result:\n\n")
  76             ;; We want the expected results displayed exactly as
  77             ;; specified in the test file, without any reordering, so
  78             ;; we override the directional properties of all of the
  79             ;; characters in the expected result by prepending
  80             ;; LRO/RLO.
  81             (cond ((string= resolved-paragraph "0")
  82                    (insert #x200e #x202d))
  83                   ((string= resolved-paragraph "1")
  84                    (insert #x200f #x202e)
  85                    ;; We need to reverse the list of indices for R2L
  86                    ;; paragraphs, so that their logical order on
  87                    ;; display matches user expectations.
  88                    (setq indices (nreverse indices))))
  89             (mapc (lambda (index)
  90                     (insert (string-to-number
  91                              (nth (string-to-number index 10) codes)
  92                              16)))
  93                   indices)
  94             (insert #x202c)     ; end the embedding
  95             (insert "\n\n"))
  96           (switch-to-buffer tbuf))
  97         (forward-line 1)
  98         (setq lnum (1+ lnum)))
  99       (switch-to-buffer output-buf)
 100       (let ((coding-system-for-write 'utf-8-unix))
 101         (write-file output-file))
 102       (message "Generating output in %s ... done" output-file))))
 103
 104 (defun biditest-create-test ()
 105   "Create a test file for testing the Emacs bidirectional display.
 106
 107 The resulting file should be viewed with `inhibit-bidi-mirroring' set to t."
 108   (biditest-generate-testfile (pop command-line-args-left)
 109                               (or (pop command-line-args-left)
 110                                   "biditest.txt")))
 111
 112 ;; A handy function for displaying the resolved bidi levels.
 113 (defun bidi-levels ()
 114   "Display the resolved bidirectional levels of characters on current line.
 115
 116 The results can be compared with the levels stated in the
 117 BidiCharacterTest.txt file."
 118   (interactive)
 119   (message "%s" (bidi-resolved-levels)))
 120
 121 (define-key global-map [f8] 'bidi-levels)