Partial fix to bug 23167
[lhc/web/wiklou.git] / includes / Html.php
index c7476f2..b56a6d0 100644 (file)
@@ -1,5 +1,5 @@
 <?php
-# Copyright (C) 2009 Aryeh Gregor
+# Copyright © 2009 Aryeh Gregor
 # http://www.mediawiki.org/
 #
 # This program is free software; you can redistribute it and/or modify
@@ -20,7 +20,7 @@
 /**
  * This class is a collection of static functions that serve two purposes:
  *
- * 1) Implement any algorithms specified by HTML 5, or other HTML
+ * 1) Implement any algorithms specified by HTML5, or other HTML
  * specifications, in a convenient and self-contained way.
  *
  * 2) Allow HTML elements to be conveniently and safely generated, like the
  * This class is meant to be confined to utility functions that are called from
  * trusted code paths.  It does not do enforcement of policy like not allowing
  * <a> elements.
+ *
+ * @since 1.16
  */
 class Html {
-       # List of void elements from HTML 5, section 9.1.2 as of 2009-08-10
+       # List of void elements from HTML5, section 9.1.2 as of 2009-08-10
        private static $voidElements = array(
                'area',
                'base',
@@ -59,7 +61,7 @@ class Html {
        );
 
        # Boolean attributes, which may have the value omitted entirely.  Manually
-       # collected from the HTML 5 spec as of 2009-08-10.
+       # collected from the HTML5 spec as of 2009-08-10.
        private static $boolAttribs = array(
                'async',
                'autobuffer',
@@ -106,12 +108,51 @@ class Html {
         * @return string Raw HTML
         */
        public static function rawElement( $element, $attribs = array(), $contents = '' ) {
+               global $wgWellFormedXml;
+               $start = self::openElement( $element, $attribs );
+               if ( in_array( $element, self::$voidElements ) ) {
+                       if ( $wgWellFormedXml ) {
+                               # Silly XML.
+                               return substr( $start, 0, -1 ) . ' />';
+                       }
+                       return $start;
+               } else {
+                       return "$start$contents" . self::closeElement( $element );
+               }
+       }
+
+       /**
+        * Identical to rawElement(), but HTML-escapes $contents (like
+        * Xml::element()).
+        */
+       public static function element( $element, $attribs = array(), $contents = '' ) {
+               return self::rawElement( $element, $attribs, strtr( $contents, array(
+                       # There's no point in escaping quotes, >, etc. in the contents of
+                       # elements.
+                       '&' => '&amp;',
+                       '<' => '&lt;'
+               ) ) );
+       }
+
+       /**
+        * Identical to rawElement(), but has no third parameter and omits the end
+        * tag (and the self-closing '/' in XML mode for empty elements).
+        */
+       public static function openElement( $element, $attribs = array() ) {
                global $wgHtml5, $wgWellFormedXml;
                $attribs = (array)$attribs;
-               # This is not required in HTML 5, but let's do it anyway, for
+               # This is not required in HTML5, but let's do it anyway, for
                # consistency and better compression.
                $element = strtolower( $element );
 
+               # In text/html, initial <html> and <head> tags can be omitted under
+               # pretty much any sane circumstances, if they have no attributes.  See:
+               # <http://www.whatwg.org/specs/web-apps/current-work/multipage/syntax.html#optional-tags>
+               if ( !$wgWellFormedXml && !$attribs
+               && in_array( $element, array( 'html', 'head' ) ) ) {
+                       return '';
+               }
+
                # Remove HTML5-only attributes if we aren't doing HTML5
                if ( !$wgHtml5 ) {
                        if ( $element == 'input' ) {
@@ -155,29 +196,38 @@ class Html {
                        }
                }
 
-               $start = "<$element" . self::expandAttributes(
-                       self::dropDefaults( $element, $attribs ) );
-               if ( in_array( $element, self::$voidElements ) ) {
-                       if ( $wgWellFormedXml ) {
-                               return "$start />";
-                       }
-                       return "$start>";
-               } else {
-                       return "$start>$contents</$element>";
-               }
+               return "<$element" . self::expandAttributes(
+                       self::dropDefaults( $element, $attribs ) ) . '>';
        }
 
        /**
-        * Identical to rawElement(), but HTML-escapes $contents (like
-        * Xml::element()).
+        * Returns "</$element>", except if $wgWellFormedXml is off, in which case
+        * it returns the empty string when that's guaranteed to be safe.
+        *
+        * @param $element string Name of the element, e.g., 'a'
+        * @return string A closing tag, if required
         */
-       public static function element( $element, $attribs = array(), $contents = '' ) {
-               return self::rawElement( $element, $attribs, strtr( $contents, array(
-                       # There's no point in escaping quotes, >, etc. in the contents of
-                       # elements.
-                       '&' => '&amp;',
-                       '<' => '&lt;'
-               ) ) );
+       public static function closeElement( $element ) {
+               global $wgWellFormedXml;
+
+               $element = strtolower( $element );
+
+               # Reference:
+               # http://www.whatwg.org/specs/web-apps/current-work/multipage/syntax.html#optional-tags
+               if ( !$wgWellFormedXml && in_array( $element, array(
+                       'html',
+                       'head',
+                       'body',
+                       'li',
+                       'dt',
+                       'dd',
+                       'tr',
+                       'td',
+                       'th',
+               ) ) ) {
+                       return '';
+               }
+               return "</$element>";
        }
 
        /**
@@ -231,7 +281,7 @@ class Html {
                        'link' => array( 'media' => 'all' ),
                        'menu' => array( 'type' => 'list' ),
                        # Note: the use of text/javascript here instead of other JavaScript
-                       # MIME types follows the HTML 5 spec.
+                       # MIME types follows the HTML5 spec.
                        'script' => array( 'type' => 'text/javascript' ),
                        'style' => array(
                                'media' => 'all',
@@ -315,11 +365,11 @@ class Html {
                                $key = $value;
                        }
 
-                       # Not technically required in HTML 5, but required in XHTML 1.0,
+                       # Not technically required in HTML5, but required in XHTML 1.0,
                        # and we'd like consistency and better compression anyway.
                        $key = strtolower( $key );
 
-                       # See the "Attributes" section in the HTML syntax part of HTML 5,
+                       # See the "Attributes" section in the HTML syntax part of HTML5,
                        # 9.1.2.3 as of 2009-08-10.  Most attributes can have quotation
                        # marks omitted, but not all.  (Although a literal " is not
                        # permitted, we don't check for that, since it will be escaped
@@ -339,7 +389,7 @@ class Html {
 
                        if ( in_array( $key, self::$boolAttribs ) ) {
                                # In XHTML 1.0 Transitional, the value needs to be equal to the
-                               # key.  In HTML 5, we can leave the value empty instead.  If we
+                               # key.  In HTML5, we can leave the value empty instead.  If we
                                # don't need well-formed XML, we can omit the = entirely.
                                if ( !$wgWellFormedXml ) {
                                        $ret .= " $key";
@@ -366,8 +416,9 @@ class Html {
                                        "\t" => '&#9;'
                                );
                                if ( $wgWellFormedXml ) {
-                                       # '<' must be escaped in attributes for XML for some
-                                       # reason, per spec: http://www.w3.org/TR/xml/#NT-AttValue
+                                       # This is allowed per spec: <http://www.w3.org/TR/xml/#NT-AttValue>
+                                       # But reportedly it breaks some XML tools?  FIXME: is this
+                                       # really true?
                                        $map['<'] = '&lt;';
                                }
                                $ret .= " $key=$quote" . strtr( $value, $map ) . $quote;
@@ -454,7 +505,7 @@ class Html {
 
        /**
         * Convenience function to produce an <input> element.  This supports the
-        * new HTML 5 input types and attributes, and will silently strip them if
+        * new HTML5 input types and attributes, and will silently strip them if
         * $wgHtml5 is false.
         *
         * @param $name    string name attribute
@@ -503,9 +554,9 @@ class Html {
                global $wgHtml5;
                $attribs['name'] = $name;
                if ( !$wgHtml5 ) {
-                       if ( !array_key_exists('cols', $attribs) )
+                       if ( !isset( $attribs['cols'] ) )
                                $attribs['cols'] = "";
-                       if ( !array_key_exists('rows', $attribs) )
+                       if ( !isset( $attribs['rows'] ) )
                                $attribs['rows'] = "";
                }
                return self::element( 'textarea', $attribs, $value );