From e4dd88023d4ae4e361d42d2c01a1a81113f7e861 Mon Sep 17 00:00:00 2001 From: Dries Buytaert Date: Thu, 10 Jun 2010 15:20:48 +0000 Subject: - Patch #768040 by jhodgdon, janusman, codycraven: truncate_utf8() only works for latin languages and drupal_substr() had a bug. --- includes/unicode.inc | 144 +++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 123 insertions(+), 21 deletions(-) (limited to 'includes/unicode.inc') diff --git a/includes/unicode.inc b/includes/unicode.inc index c3638c9a8..2813a5739 100644 --- a/includes/unicode.inc +++ b/includes/unicode.inc @@ -17,6 +17,67 @@ define('UNICODE_SINGLEBYTE', 0); */ define('UNICODE_MULTIBYTE', 1); +/** + * Matches Unicode characters that are word boundaries. + * + * @see http://unicode.org/glossary + * + * Characters with the following General_category (gc) property values are used + * as word boundaries. While this does not fully conform to the Word Boundaries + * algorithm described in http://unicode.org/reports/tr29, as PCRE does not + * contain the Word_Break property table, this simpler algorithm has to do. + * - Cc, Cf, Cn, Co, Cs: Other. + * - Pc, Pd, Pe, Pf, Pi, Po, Ps: Punctuation. + * - Sc, Sk, Sm, So: Symbols. + * - Zl, Zp, Zs: Separators. + * + * Non-boundary characters include the following General_category (gc) property + * values: + * - Ll, Lm, Lo, Lt, Lu: Letters. + * - Mc, Me, Mn: Combining Marks. + * - Nd, Nl, No: Numbers. + * + * Note that the PCRE property matcher is not used because we wanted to be + * compatible with Unicode 5.2.0 regardless of the PCRE version used (and any + * bugs in PCRE property tables). + */ +define('PREG_CLASS_UNICODE_WORD_BOUNDARY', + '\x{0}-\x{2F}\x{3A}-\x{40}\x{5B}-\x{60}\x{7B}-\x{A9}\x{AB}-\x{B1}\x{B4}' . + '\x{B6}-\x{B8}\x{BB}\x{BF}\x{D7}\x{F7}\x{2C2}-\x{2C5}\x{2D2}-\x{2DF}' . + '\x{2E5}-\x{2EB}\x{2ED}\x{2EF}-\x{2FF}\x{375}\x{37E}-\x{385}\x{387}\x{3F6}' . + '\x{482}\x{55A}-\x{55F}\x{589}-\x{58A}\x{5BE}\x{5C0}\x{5C3}\x{5C6}' . + '\x{5F3}-\x{60F}\x{61B}-\x{61F}\x{66A}-\x{66D}\x{6D4}\x{6DD}\x{6E9}' . + '\x{6FD}-\x{6FE}\x{700}-\x{70F}\x{7F6}-\x{7F9}\x{830}-\x{83E}' . + '\x{964}-\x{965}\x{970}\x{9F2}-\x{9F3}\x{9FA}-\x{9FB}\x{AF1}\x{B70}' . + '\x{BF3}-\x{BFA}\x{C7F}\x{CF1}-\x{CF2}\x{D79}\x{DF4}\x{E3F}\x{E4F}' . + '\x{E5A}-\x{E5B}\x{F01}-\x{F17}\x{F1A}-\x{F1F}\x{F34}\x{F36}\x{F38}' . + '\x{F3A}-\x{F3D}\x{F85}\x{FBE}-\x{FC5}\x{FC7}-\x{FD8}\x{104A}-\x{104F}' . + '\x{109E}-\x{109F}\x{10FB}\x{1360}-\x{1368}\x{1390}-\x{1399}\x{1400}' . + '\x{166D}-\x{166E}\x{1680}\x{169B}-\x{169C}\x{16EB}-\x{16ED}' . + '\x{1735}-\x{1736}\x{17B4}-\x{17B5}\x{17D4}-\x{17D6}\x{17D8}-\x{17DB}' . + '\x{1800}-\x{180A}\x{180E}\x{1940}-\x{1945}\x{19DE}-\x{19FF}' . + '\x{1A1E}-\x{1A1F}\x{1AA0}-\x{1AA6}\x{1AA8}-\x{1AAD}\x{1B5A}-\x{1B6A}' . + '\x{1B74}-\x{1B7C}\x{1C3B}-\x{1C3F}\x{1C7E}-\x{1C7F}\x{1CD3}\x{1FBD}' . + '\x{1FBF}-\x{1FC1}\x{1FCD}-\x{1FCF}\x{1FDD}-\x{1FDF}\x{1FED}-\x{1FEF}' . + '\x{1FFD}-\x{206F}\x{207A}-\x{207E}\x{208A}-\x{208E}\x{20A0}-\x{20B8}' . + '\x{2100}-\x{2101}\x{2103}-\x{2106}\x{2108}-\x{2109}\x{2114}' . + '\x{2116}-\x{2118}\x{211E}-\x{2123}\x{2125}\x{2127}\x{2129}\x{212E}' . + '\x{213A}-\x{213B}\x{2140}-\x{2144}\x{214A}-\x{214D}\x{214F}' . + '\x{2190}-\x{244A}\x{249C}-\x{24E9}\x{2500}-\x{2775}\x{2794}-\x{2B59}' . + '\x{2CE5}-\x{2CEA}\x{2CF9}-\x{2CFC}\x{2CFE}-\x{2CFF}\x{2E00}-\x{2E2E}' . + '\x{2E30}-\x{3004}\x{3008}-\x{3020}\x{3030}\x{3036}-\x{3037}' . + '\x{303D}-\x{303F}\x{309B}-\x{309C}\x{30A0}\x{30FB}\x{3190}-\x{3191}' . + '\x{3196}-\x{319F}\x{31C0}-\x{31E3}\x{3200}-\x{321E}\x{322A}-\x{3250}' . + '\x{3260}-\x{327F}\x{328A}-\x{32B0}\x{32C0}-\x{33FF}\x{4DC0}-\x{4DFF}' . + '\x{A490}-\x{A4C6}\x{A4FE}-\x{A4FF}\x{A60D}-\x{A60F}\x{A673}\x{A67E}' . + '\x{A6F2}-\x{A716}\x{A720}-\x{A721}\x{A789}-\x{A78A}\x{A828}-\x{A82B}' . + '\x{A836}-\x{A839}\x{A874}-\x{A877}\x{A8CE}-\x{A8CF}\x{A8F8}-\x{A8FA}' . + '\x{A92E}-\x{A92F}\x{A95F}\x{A9C1}-\x{A9CD}\x{A9DE}-\x{A9DF}' . + '\x{AA5C}-\x{AA5F}\x{AA77}-\x{AA79}\x{AADE}-\x{AADF}\x{ABEB}' . + '\x{D800}-\x{F8FF}\x{FB29}\x{FD3E}-\x{FD3F}\x{FDFC}-\x{FDFD}' . + '\x{FE10}-\x{FE19}\x{FE30}-\x{FE6B}\x{FEFF}-\x{FF0F}\x{FF1A}-\x{FF20}' . + '\x{FF3B}-\x{FF40}\x{FF5B}-\x{FF65}\x{FFE0}-\x{FFFD}'); + /** * Wrapper around _unicode_check(). */ @@ -213,44 +274,80 @@ function drupal_truncate_bytes($string, $len) { } /** - * Truncate a UTF-8-encoded string safely to a number of characters. + * Truncates a UTF-8-encoded string safely to a number of characters. * * @param $string * The string to truncate. - * @param $len - * An upper limit on the returned string length. + * @param $max_length + * An upper limit on the returned string length, including trailing ellipsis + * if $add_ellipsis is TRUE. * @param $wordsafe - * Flag to truncate at last space within the upper limit. Defaults to FALSE. - * @param $dots - * Flag to add trailing dots. Defaults to FALSE. + * If TRUE, attempt to truncate on a word boundary. Word boundaries are + * spaces, punctuation, and Unicode characters used as word boundaries in + * non-Latin languages; see PREG_CLASS_UNICODE_WORD_BOUNDARY for more + * information. If a word boundary cannot be found that would make the length + * of the returned string fall within length guidelines (see parameters + * $max_return_length and $min_wordsafe_length), word boundaries are ignored. + * @param $add_ellipsis + * If TRUE, add t('...') to the end of the truncated string (defaults to + * FALSE). The string length will still fall within $max_return_length. + * @param $min_wordsafe_length + * If $wordsafe is TRUE, the minimum acceptable length for truncation (before + * adding an ellipsis, if $add_ellipsis is TRUE). Has no effect if $wordsafe + * is FALSE. This can be used to prevent having a very short resulting string + * that will not be understandable. For instance, if you are truncating the + * string "See myverylongurlexample.com for more information" to a word-safe + * return length of 20, the only available word boundary within 20 characters + * is after the word "See", which wouldn't leave a very informative string. If + * you had set $min_wordsafe_length to 10, though, the function would realise + * that "See" alone is too short, and would then just truncate ignoring word + * boundaries, giving you "See myverylongurl..." (assuming you had set + * $add_ellipses to TRUE). + * * @return * The truncated string. */ -function truncate_utf8($string, $len, $wordsafe = FALSE, $dots = FALSE) { +function truncate_utf8($string, $max_length, $wordsafe = FALSE, $add_ellipsis = FALSE, $min_wordsafe_length = 1) { + $ellipsis = ''; + $max_length = max($max_length, 0); + $min_wordsafe_length = max($min_wordsafe_length, 0); - if (drupal_strlen($string) <= $len) { + if (drupal_strlen($string) <= $max_length) { + // No truncation needed, so don't add ellipsis, just return. return $string; } - if ($dots) { - $len -= 4; + if ($add_ellipsis) { + // Truncate ellipsis in case $max_length is small. + $ellipsis = drupal_substr(t('...'), 0, $max_length); + $max_length -= drupal_strlen($ellipsis); + $max_length = max($max_length, 0); + } + + if ($max_length <= $min_wordsafe_length) { + // Do not attempt word-safe if lengths are bad. + $wordsafe = FALSE; } if ($wordsafe) { - $string = drupal_substr($string, 0, $len + 1); // leave one more character - if ($last_space = strrpos($string, ' ')) { // space exists AND is not on position 0 - $string = substr($string, 0, $last_space); + $matches = array(); + // Find the last word boundary, if there is one within $min_wordsafe_length + // to $max_length characters. preg_match() is always greedy, so it will + // find the longest string possible. + $found = preg_match('/^(.{' . $min_wordsafe_length . ',' . $max_length . '})[' . PREG_CLASS_UNICODE_WORD_BOUNDARY . ']/u', $string, $matches); + if ($found) { + $string = $matches[1]; } else { - $string = drupal_substr($string, 0, $len); + $string = drupal_substr($string, 0, $max_length); } } else { - $string = drupal_substr($string, 0, $len); + $string = drupal_substr($string, 0, $max_length); } - if ($dots) { - $string .= ' ...'; + if ($add_ellipsis) { + $string .= $ellipsis; } return $string; @@ -516,16 +613,21 @@ function drupal_substr($text, $start, $length = NULL) { // Count all the continuation bytes from the starting index until we have // found $length characters or reached the end of the string, then // backtrace one byte. - $iend = $istart - 1; $chars = -1; + $iend = $istart - 1; + $chars = -1; + $last_real = FALSE; while ($iend < $strlen - 1 && $chars < $length) { $iend++; $c = ord($text[$iend]); + $last_real = FALSE; if ($c < 0x80 || $c >= 0xC0) { $chars++; + $last_real = TRUE; } } - // Backtrace one byte if the end of the string was not reached. - if ($iend < $strlen - 1) { + // Backtrace one byte if the last character we found was a real character + // and we don't need it. + if ($last_real && $chars >= $length) { $iend--; } } @@ -548,7 +650,7 @@ function drupal_substr($text, $start, $length = NULL) { } else { // $length == 0, return an empty string. - $iend = $istart - 1; + return ''; } return substr($text, $istart, max(0, $iend - $istart + 1)); -- cgit v1.2.3