Doxygen: Rewrite mwdoc-filter to fix bug with slashes in comments

The behaviour stays the same (extract type from @var comment and
insert into source code between e.g. "protected" and "$name") but
implemented using PHP's tokenizer instead of global regexes.

This fixes the problem with slashes being found inside the
documentation comment and various other edge cases, such as use
of slashes inside comments.

Also fix the problem with PHP namespaces being misinterpreted
as a Doxygen /command by escaping slashes automatically. This
shouldn't conflict with actual commands, since we use '@' for
all commands (e.g. @param, @return, @since etc.)

Change-Id: Ic03a8fc9d4b4851f66c2e975d9955ba20ab92f0e

diff --git a/maintenance/mwdoc-filter.php b/maintenance/mwdoc-filter.php
index 0cc7bde..ed63c5c 100644 (file)
--- a/maintenance/mwdoc-filter.php
+++ b/maintenance/mwdoc-filter.php
@@ -2,13 +2,40 @@
 /**
  * Doxygen filter to show correct member variable types in documentation.
  *
- * Should be filled in doxygen INPUT_FILTER as "php mwdoc-filter.php"
+ * Should be set in Doxygen INPUT_FILTER as "php mwdoc-filter.php"
  *
- * Original source code by Goran Rakic
- * http://blog.goranrakic.com/
- * http://stackoverflow.com/questions/4325224
+ * Based on
+ * <http://virtualtee.blogspot.co.uk/2012/03/tip-for-using-doxygen-for-php-code.html>
  *
- * @file
+ * Improved to resolve various bugs and better MediaWiki PHPDoc conventions:
+ *
+ * - Insert variable name after typehint instead of at end of line so that
+ *   documentation text may follow after "@var Type".
+ * - Insert typehint into source code before $variable instead of inside the comment
+ *   so that Doxygen interprets it.
+ * - Strip the text after @var from the output to avoid Doxygen warnings aboug bogus
+ *   symbols being documented but not declared or defined.
+ *
+ * Copyright (C) 2012 Tamas Imrei <tamas.imrei@gmail.com> http://virtualtee.blogspot.com/
+ * Copyright (C) 2015 Timo Tijhof
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
  */
 
 if ( PHP_SAPI != 'cli' ) {
@@ -16,33 +43,58 @@ if ( PHP_SAPI != 'cli' ) {
 }
 
 $source = file_get_contents( $argv[1] );
-$regexp = '#'
-       . '\@var'
-       . '\s+'
-       // Type hint
-       . '([^\s]+)'
-       . '\s+'
-       // Any text or line(s) between type hint and '/' closing the comment
-       // (includes the star of "*/"). Descriptions containing a slash
-       // are not supported. Those will have to to be rewritten to have their
-       // description *before* the @var:
-       // /**
-       //  * Description with / in it.
-       //  * @var array
-       //  */
-       // instead of:
-       // /**
-       //  * @var array Description with / in it.
-       //  */
-       . '([^/]+)'
-       . '/'
-       . '\s+'
-       . '(var|public|protected|private)'
-       . '\s+'
-       // Variable name
-       . '(\$[^\s;=]+)'
-       . '#';
-$replac = '${2}/ ${3} ${1} ${4}';
-$source = preg_replace( $regexp, $replac, $source );
+$tokens = token_get_all( $source );
+
+$buffer = $bufferType = null;
+foreach ( $tokens as $token ) {
+       if ( is_string( $token ) ) {
+               if ( $buffer !== null && $token === ';' ) {
+                       // If we still have a buffer and the statement has ended,
+                       // flush it and move on.
+                       echo $buffer;
+                       $buffer = $bufferType = null;
+               }
+               echo $token;
+               continue;
+       }
+       list( $id, $content ) = $token;
+       switch ( $id ) {
+               case T_DOC_COMMENT:
+                       // Escape slashes so that references to namespaces are not
+                       // wrongly interpreted as a Doxygen "\command".
+                       $content = addcslashes( $content, '\\' );
+                       // Look for instances of "@var Type" not followed by $name.
+                       if ( preg_match( '#@var\s+([^\s]+)\s+([^\$]+)#s', $content ) ) {
+                               $buffer = preg_replace_callback(
+                                       // Strip the "@var Type" part and remember the type
+                                       '#(@var\s+)([^\s]+)#s',
+                                       function ( $matches ) use ( &$bufferType ) {
+                                               $bufferType = $matches[2];
+                                               return '';
+                                       },
+                                       $content
+                               );
+                       } else {
+                               echo $content;
+                       }
+                       break;
 
-echo $source;
+               case T_VARIABLE:
+                       if ( $buffer !== null ) {
+                               echo $buffer;
+                               echo "$bufferType $content";
+                               $buffer = $bufferType = null;
+                       } else {
+                               echo $content;
+                       }
+                       break;
+
+               default:
+                       if ( $buffer !== null ) {
+                               $buffer .= $content;
+                       } else {
+                               echo $content;
+                       }
+                       break;
+       }
+}