I had this parser comparer in my working copy since the summer.

diff --git a/maintenance/compareParsers.php b/maintenance/compareParsers.php
new file mode 100644 (file)
index 0000000..9f7ec19
--- /dev/null
+++ b/maintenance/compareParsers.php
@@ -0,0 +1,194 @@
+<?php
+/**
+ * Take page text out of an XML dump file and render basic HTML out to files.
+ * This is *NOT* suitable for publishing or offline use; it's intended for
+ * running comparative tests of parsing behavior using real-world data.
+ *
+ * Templates etc are pulled from the local wiki database, not from the dump.
+ *
+ * Copyright (C) 2011 Platonides - http://www.mediawiki.org/
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Maintenance
+ */
+ 
+require_once( dirname( __FILE__ ) . '/Maintenance.php' );
+
+class CompareParsers extends Maintenance {
+
+       private $count = 0;
+       private $outputDirectory, $startTime;
+
+       public function __construct() {
+               parent::__construct();
+               $this->saveFailed = false;
+               $this->mDescription = "Run a file or dump with several parsers";
+               $this->addOption( 'parser1', 'The first parser to compare.', true, true );
+               $this->addOption( 'parser2', 'The second parser to compare.', true, true );
+               $this->addOption( 'file', 'File with text to run.', false, true );
+               $this->addOption( 'dump', 'XML dump to execute all revisions.', false, true );
+               $this->addOption( 'from', 'Article from XML dump to start from.', false, true );
+               $this->addOption( 'tidy', 'Run tidy on the articles.', false, false );
+               $this->addOption( 'save-failed', 'Folder in which articles which differ will be stored.', false, true );
+               $this->addOption( 'show-diff', 'Show a diff of the two renderings.', false, false );
+               $this->addOption( 'diff-bin', 'Binary to use for diffing (can also be provided by DIFF env var).', false, false );
+               $this->addOption( 'strip-parameters', 'Remove parameters of html tags to increase readability.', false, false );
+               $this->addOption( 'show-parsed-output', 'Show the parsed html if both Parsers give the same output.', false, false );
+       }
+
+       public function execute() {
+               if (! ( $this->hasOption('file') ^ $this->hasOption('dump') ) ) {
+                       $this->error("You must provide file or dump", true);
+               }
+
+               if ( $this->hasOption('save-failed') ) {
+                       $this->saveFailed = $this->getOption('save-failed');
+               }
+               
+               $this->stripParametersEnabled = $this->hasOption( 'strip-parameters' );
+               $this->showParsedOutput = $this->hasOption( 'show-parsed-output' );
+               
+               $this->showDiff = $this->hasOption( 'show-diff' );
+               if ( $this->showDiff ) {
+                       $bin = $this->getOption( 'diff-bin', getenv( 'DIFF' ) );
+                       if ( $bin != '' ) {
+                               global $wgDiff;
+                               $wgDiff = $bin;
+                       }
+               }
+               
+               $user = new User();             
+               $this->options = ParserOptions::newFromUser( $user );
+               
+               if ( $this->hasOption( 'tidy' ) ) {
+                       global $wgUseTidy;
+                       if ( !$wgUseTidy ) {
+                               $this->error( 'Tidy was requested but $wgUseTidy is not set in LocalSettings.php', true );
+                       }
+                       $this->options->setTidy( true );
+               }
+               
+               if ( $this->hasOption('file') ) {
+                       $revision = new WikiRevision;
+                       
+                       $revision->setText( file_get_contents( $this->getOption('file') ) );
+                       $revision->setTitle( Title::newFromText( rawurldecode( basename( $this->getOption('file'), '.txt' ) ) ) );
+                       $this->handleRevision( $revision );
+                       return;
+               }
+               
+               $this->startTime = wfTime();
+
+               if ( $this->getOption('dump') == '-' ) {
+                       $source = new ImportStreamSource( $this->getStdin() );
+               } else {
+                       $this->error("Sorry, I don't support dump filenames yet. Use - and provide it on stdin on the meantime.", true);
+               }
+               $importer = new WikiImporter( $source );
+
+               $importer->setRevisionCallback(
+                       array( &$this, 'handleRevision' ) );
+               
+               $this->from = $this->getOption( 'from', null );
+               $this->count = 0;
+               $this->failed = 0;
+               $importer->doImport();
+               
+               $this->error( "{$this->failed} failed revisions out of {$this->count}" );
+               if ($this->count > 0)
+                       $this->output( " (" . ( $this->failed / $this->count ) . "%)\n" );
+                       
+               $delta = wfTime() - $this->startTime;
+               $this->error( "Compared {$this->count} pages in " . round($delta, 2) . " seconds " );
+               if ($delta > 0)
+                       $this->error( round($this->count / $delta, 2) . " pages/sec" );
+               $this->error( "\n" );
+       }
+       
+       function stripParameters( $text ) {
+               if ( !$this->stripParametersEnabled ) {
+                       return $text;
+               }
+               return preg_replace( '/(<a) [^>]+>/', '$1>', $text );
+       }
+       
+       /**
+        * Callback function for each revision, parse with both parsers and compare
+        * @param $rev Revision
+        */
+       public function handleRevision( $rev ) {
+               $title = $rev->getTitle();
+               if ( !$title ) {
+                       $this->error( "Got bogus revision with null title!" );
+                       return;
+               }
+               
+               $this->count++;
+               if ( isset( $this->from ) ) {
+                       if ( $this->from != $title )
+                               return;
+                       $this->output( "Skipped " . ($this->count - 1) . " pages\n" );
+                       
+                       $this->count = 1;
+                       $this->from = null;
+               }
+               
+               
+
+               $parser1Name = $this->getOption( 'parser1' );
+               $parser2Name = $this->getOption( 'parser2' );
+               
+               self::checkParserLocally( $parser1Name );
+               self::checkParserLocally( $parser2Name );
+               
+               $parser1 = new $parser1Name();
+               $parser2 = new $parser2Name();
+               
+               $output1 = $parser1->parse( $rev->getText(), $title, $this->options );
+               $output2 = $parser2->parse( $rev->getText(), $title, $this->options );
+
+               if ( $output1->getText() != $output2->getText() ) {
+                       $this->failed++;
+                       $this->error( "Parsing for {$title->getPrefixedText()} differs\n" );
+                       
+                       if ($this->saveFailed) {
+                               file_put_contents( $this->saveFailed . '/' . rawurlencode( $title->getPrefixedText() ) . ".txt", $rev->getText());
+                       }
+                       if ( $this->showDiff ) {
+                               $this->output( wfDiff( $this->stripParameters( $output1->getText() ), $this->stripParameters( $output2->getText() ), '' ) );
+                       }
+               } else {
+                       $this->output( $title->getPrefixedText() . "\tOK\n" );
+                       if ( $this->showParsedOutput ) {
+                               $this->output( $this->stripParameters( $output1->getText() ) );
+                       }
+               }
+       }
+       
+       private static function checkParserLocally( $parserName ) {
+               /* Look for the parser in a file appropiately named in the current folder */
+               if ( !class_exists( $parserName ) && file_exists( "$parserName.php" ) ) {
+                       global $wgAutoloadClasses;
+                       $wgAutoloadClasses[ $parserName ] = realpath( '.' ) . "/$parserName.php";
+               }
+       }
+
+}
+
+$maintClass = "CompareParsers";
+require_once( DO_MAINTENANCE );