3 * WordPress Diff bastard child of old MediaWiki Diff Formatter.
5 * Basically all that remains is the table structure and some method names.
11 if ( ! class_exists( 'Text_Diff', false ) ) {
12 /** Text_Diff class */
13 require( dirname(__FILE__).'/Text/Diff.php' );
14 /** Text_Diff_Renderer class */
15 require( dirname(__FILE__).'/Text/Diff/Renderer.php' );
16 /** Text_Diff_Renderer_inline class */
17 require( dirname(__FILE__).'/Text/Diff/Renderer/inline.php' );
21 * Table renderer to display the diff lines.
24 * @uses Text_Diff_Renderer Extends
26 class WP_Text_Diff_Renderer_Table extends Text_Diff_Renderer {
29 * @see Text_Diff_Renderer::_leading_context_lines
34 public $_leading_context_lines = 10000;
37 * @see Text_Diff_Renderer::_trailing_context_lines
42 public $_trailing_context_lines = 10000;
45 * Threshold for when a diff should be saved or omitted.
51 protected $_diff_threshold = 0.6;
54 * Inline display helper object name.
60 protected $inline_diff_renderer = 'WP_Text_Diff_Renderer_inline';
63 * Should we show the split view or not
69 protected $_show_split_view = true;
71 protected $compat_fields = array( '_show_split_view', 'inline_diff_renderer', '_diff_threshold' );
74 * Constructor - Call parent constructor with params array.
76 * This will set class properties based on the key value pairs in the array.
80 * @param array $params
82 public function __construct( $params = array() ) {
83 parent::__construct( $params );
84 if ( isset( $params[ 'show_split_view' ] ) )
85 $this->_show_split_view = $params[ 'show_split_view' ];
91 * @param string $header
94 public function _startBlock( $header ) {
101 * @param array $lines
102 * @param string $prefix
104 public function _lines( $lines, $prefix=' ' ) {
110 * @param string $line HTML-escape the value.
113 public function addedLine( $line ) {
114 return "<td class='diff-addedline'>{$line}</td>";
121 * @param string $line HTML-escape the value.
124 public function deletedLine( $line ) {
125 return "<td class='diff-deletedline'>{$line}</td>";
131 * @param string $line HTML-escape the value.
134 public function contextLine( $line ) {
135 return "<td class='diff-context'>{$line}</td>";
143 public function emptyLine() {
144 return '<td> </td>';
151 * @param array $lines
152 * @param bool $encode
155 public function _added( $lines, $encode = true ) {
157 foreach ($lines as $line) {
159 $processed_line = htmlspecialchars( $line );
162 * Contextually filters a diffed line.
164 * Filters TextDiff processing of diffed line. By default, diffs are processed with
165 * htmlspecialchars. Use this filter to remove or change the processing. Passes a context
166 * indicating if the line is added, deleted or unchanged.
170 * @param String $processed_line The processed diffed line.
171 * @param String $line The unprocessed diffed line.
172 * @param string null The line context. Values are 'added', 'deleted' or 'unchanged'.
174 $line = apply_filters( 'process_text_diff_html', $processed_line, $line, 'added' );
177 if ( $this->_show_split_view ) {
178 $r .= '<tr>' . $this->emptyLine() . $this->emptyLine() . $this->addedLine( $line ) . "</tr>\n";
180 $r .= '<tr>' . $this->addedLine( $line ) . "</tr>\n";
190 * @param array $lines
191 * @param bool $encode
194 public function _deleted( $lines, $encode = true ) {
196 foreach ($lines as $line) {
198 $processed_line = htmlspecialchars( $line );
200 /** This filter is documented in wp-includes/wp-diff.php */
201 $line = apply_filters( 'process_text_diff_html', $processed_line, $line, 'deleted' );
203 if ( $this->_show_split_view ) {
204 $r .= '<tr>' . $this->deletedLine( $line ) . $this->emptyLine() . $this->emptyLine() . "</tr>\n";
206 $r .= '<tr>' . $this->deletedLine( $line ) . "</tr>\n";
217 * @param array $lines
218 * @param bool $encode
221 public function _context( $lines, $encode = true ) {
223 foreach ($lines as $line) {
225 $processed_line = htmlspecialchars( $line );
227 /** This filter is documented in wp-includes/wp-diff.php */
228 $line = apply_filters( 'process_text_diff_html', $processed_line, $line, 'unchanged' );
230 if ( $this->_show_split_view ) {
231 $r .= '<tr>' . $this->contextLine( $line ) . $this->emptyLine() . $this->contextLine( $line ) . "</tr>\n";
233 $r .= '<tr>' . $this->contextLine( $line ) . "</tr>\n";
240 * Process changed lines to do word-by-word diffs for extra highlighting.
242 * (TRAC style) sometimes these lines can actually be deleted or added rows.
243 * We do additional processing to figure that out
249 * @param array $final
252 public function _changed( $orig, $final ) {
255 // Does the aforementioned additional processing
256 // *_matches tell what rows are "the same" in orig and final. Those pairs will be diffed to get word changes
257 // match is numeric: an index in other column
258 // match is 'X': no match. It is a new row
259 // *_rows are column vectors for the orig column and the final column.
260 // row >= 0: an indix of the $orig or $final array
261 // row < 0: a blank row for that column
262 list($orig_matches, $final_matches, $orig_rows, $final_rows) = $this->interleave_changed_lines( $orig, $final );
264 // These will hold the word changes as determined by an inline diff
265 $orig_diffs = array();
266 $final_diffs = array();
268 // Compute word diffs for each matched pair using the inline diff
269 foreach ( $orig_matches as $o => $f ) {
270 if ( is_numeric($o) && is_numeric($f) ) {
271 $text_diff = new Text_Diff( 'auto', array( array($orig[$o]), array($final[$f]) ) );
272 $renderer = new $this->inline_diff_renderer;
273 $diff = $renderer->render( $text_diff );
275 // If they're too different, don't include any <ins> or <dels>
276 if ( preg_match_all( '!(<ins>.*?</ins>|<del>.*?</del>)!', $diff, $diff_matches ) ) {
277 // length of all text between <ins> or <del>
278 $stripped_matches = strlen(strip_tags( join(' ', $diff_matches[0]) ));
279 // since we count lengith of text between <ins> or <del> (instead of picking just one),
280 // we double the length of chars not in those tags.
281 $stripped_diff = strlen(strip_tags( $diff )) * 2 - $stripped_matches;
282 $diff_ratio = $stripped_matches / $stripped_diff;
283 if ( $diff_ratio > $this->_diff_threshold )
284 continue; // Too different. Don't save diffs.
287 // Un-inline the diffs by removing del or ins
288 $orig_diffs[$o] = preg_replace( '|<ins>.*?</ins>|', '', $diff );
289 $final_diffs[$f] = preg_replace( '|<del>.*?</del>|', '', $diff );
293 foreach ( array_keys($orig_rows) as $row ) {
294 // Both columns have blanks. Ignore them.
295 if ( $orig_rows[$row] < 0 && $final_rows[$row] < 0 )
298 // If we have a word based diff, use it. Otherwise, use the normal line.
299 if ( isset( $orig_diffs[$orig_rows[$row]] ) )
300 $orig_line = $orig_diffs[$orig_rows[$row]];
301 elseif ( isset( $orig[$orig_rows[$row]] ) )
302 $orig_line = htmlspecialchars($orig[$orig_rows[$row]]);
306 if ( isset( $final_diffs[$final_rows[$row]] ) )
307 $final_line = $final_diffs[$final_rows[$row]];
308 elseif ( isset( $final[$final_rows[$row]] ) )
309 $final_line = htmlspecialchars($final[$final_rows[$row]]);
313 if ( $orig_rows[$row] < 0 ) { // Orig is blank. This is really an added row.
314 $r .= $this->_added( array($final_line), false );
315 } elseif ( $final_rows[$row] < 0 ) { // Final is blank. This is really a deleted row.
316 $r .= $this->_deleted( array($orig_line), false );
317 } else { // A true changed row.
318 if ( $this->_show_split_view ) {
319 $r .= '<tr>' . $this->deletedLine( $orig_line ) . $this->emptyLine() . $this->addedLine( $final_line ) . "</tr>\n";
321 $r .= '<tr>' . $this->deletedLine( $orig_line ) . "</tr><tr>" . $this->addedLine( $final_line ) . "</tr>\n";
330 * Takes changed blocks and matches which rows in orig turned into which rows in final.
333 * *_matches ( which rows match with which )
334 * *_rows ( order of rows in each column interleaved with blank rows as
340 * @param array $final
343 public function interleave_changed_lines( $orig, $final ) {
345 // Contains all pairwise string comparisons. Keys are such that this need only be a one dimensional array.
347 foreach ( array_keys($orig) as $o ) {
348 foreach ( array_keys($final) as $f ) {
349 $matches["$o,$f"] = $this->compute_string_distance( $orig[$o], $final[$f] );
352 asort($matches); // Order by string distance.
354 $orig_matches = array();
355 $final_matches = array();
357 foreach ( $matches as $keys => $difference ) {
358 list($o, $f) = explode(',', $keys);
362 // Already have better matches for these guys
363 if ( isset($orig_matches[$o]) && isset($final_matches[$f]) )
366 // First match for these guys. Must be best match
367 if ( !isset($orig_matches[$o]) && !isset($final_matches[$f]) ) {
368 $orig_matches[$o] = $f;
369 $final_matches[$f] = $o;
373 // Best match of this final is already taken? Must mean this final is a new row.
374 if ( isset($orig_matches[$o]) )
375 $final_matches[$f] = 'x';
377 // Best match of this orig is already taken? Must mean this orig is a deleted row.
378 elseif ( isset($final_matches[$f]) )
379 $orig_matches[$o] = 'x';
382 // We read the text in this order
383 ksort($orig_matches);
384 ksort($final_matches);
386 // Stores rows and blanks for each column.
387 $orig_rows = $orig_rows_copy = array_keys($orig_matches);
388 $final_rows = array_keys($final_matches);
390 // Interleaves rows with blanks to keep matches aligned.
391 // We may end up with some extraneous blank rows, but we'll just ignore them later.
392 foreach ( $orig_rows_copy as $orig_row ) {
393 $final_pos = array_search($orig_matches[$orig_row], $final_rows, true);
394 $orig_pos = (int) array_search($orig_row, $orig_rows, true);
396 if ( false === $final_pos ) { // This orig is paired with a blank final.
397 array_splice( $final_rows, $orig_pos, 0, -1 );
398 } elseif ( $final_pos < $orig_pos ) { // This orig's match is up a ways. Pad final with blank rows.
399 $diff_pos = $final_pos - $orig_pos;
400 while ( $diff_pos < 0 )
401 array_splice( $final_rows, $orig_pos, 0, $diff_pos++ );
402 } elseif ( $final_pos > $orig_pos ) { // This orig's match is down a ways. Pad orig with blank rows.
403 $diff_pos = $orig_pos - $final_pos;
404 while ( $diff_pos < 0 )
405 array_splice( $orig_rows, $orig_pos, 0, $diff_pos++ );
409 // Pad the ends with blank rows if the columns aren't the same length
410 $diff_count = count($orig_rows) - count($final_rows);
411 if ( $diff_count < 0 ) {
412 while ( $diff_count < 0 )
413 array_push($orig_rows, $diff_count++);
414 } elseif ( $diff_count > 0 ) {
415 $diff_count = -1 * $diff_count;
416 while ( $diff_count < 0 )
417 array_push($final_rows, $diff_count++);
420 return array($orig_matches, $final_matches, $orig_rows, $final_rows);
424 * Computes a number that is intended to reflect the "distance" between two strings.
428 * @param string $string1
429 * @param string $string2
432 public function compute_string_distance( $string1, $string2 ) {
433 // Vectors containing character frequency for all chars in each string
434 $chars1 = count_chars($string1);
435 $chars2 = count_chars($string2);
437 // L1-norm of difference vector.
438 $difference = array_sum( array_map( array($this, 'difference'), $chars1, $chars2 ) );
440 // $string1 has zero length? Odd. Give huge penalty by not dividing.
444 // Return distance per character (of string1).
445 return $difference / strlen($string1);
456 public function difference( $a, $b ) {
457 return abs( $a - $b );
461 * Make private properties readable for backward compatibility.
466 * @param string $name Property to get.
467 * @return mixed Property.
469 public function __get( $name ) {
470 if ( in_array( $name, $this->compat_fields ) ) {
476 * Make private properties settable for backward compatibility.
481 * @param string $name Property to check if set.
482 * @param mixed $value Property value.
483 * @return mixed Newly-set property.
485 public function __set( $name, $value ) {
486 if ( in_array( $name, $this->compat_fields ) ) {
487 return $this->$name = $value;
492 * Make private properties checkable for backward compatibility.
497 * @param string $name Property to check if set.
498 * @return bool Whether the property is set.
500 public function __isset( $name ) {
501 if ( in_array( $name, $this->compat_fields ) ) {
502 return isset( $this->$name );
507 * Make private properties un-settable for backward compatibility.
512 * @param string $name Property to unset.
514 public function __unset( $name ) {
515 if ( in_array( $name, $this->compat_fields ) ) {
516 unset( $this->$name );
522 * Better word splitting than the PEAR package provides.
525 * @uses Text_Diff_Renderer_inline Extends
527 class WP_Text_Diff_Renderer_inline extends Text_Diff_Renderer_inline {
533 * @param string $string
534 * @param string $newlineEscape
537 public function _splitOnWords($string, $newlineEscape = "\n") {
538 $string = str_replace("\0", '', $string);
539 $words = preg_split( '/([^\w])/u', $string, -1, PREG_SPLIT_DELIM_CAPTURE );
540 $words = str_replace( "\n", $newlineEscape, $words );