vendor/wikimedia/remex-html/RemexHtml/TreeBuilder/TreeMutationTracer.php

   1 <?php
   2
   3 namespace RemexHtml\TreeBuilder;
   4 use RemexHtml\Tokenizer\Attributes;
   5
   6 /**
   7  * This is a debugging helper class which calls the supplied callback function
   8  * each time there is a TreeHandler event, giving a descriptive message. It
   9  * then forwards the event through to the supplied handler.
  10  */
  11 class TreeMutationTracer implements TreeHandler {
  12
  13         /**
  14          * Constructor.
  15          *
  16          * @param TreeHandler $handler The next pipeline stage
  17          * @param callable $callback The message output function
  18          * @param integer $verbosity Set to non-zero to call dump() on the handler
  19          *   before and after each event.
  20          */
  21         public function __construct( TreeHandler $handler, callable $callback, $verbosity = 0 ) {
  22                 $this->handler = $handler;
  23                 $this->callback = $callback;
  24                 $this->verbosity = $verbosity;
  25         }
  26
  27         /**
  28          * Send a message
  29          */
  30         private function trace( $msg ) {
  31                 call_user_func( $this->callback, "[Tree] $msg" );
  32         }
  33
  34         /**
  35          * Get a debug tag for an element or null
  36          *
  37          * @param Element|null $element
  38          */
  39         private function getDebugTag( $element ) {
  40                 return $element ? $element->getDebugTag() : '';
  41         }
  42
  43         /**
  44          * Get a short excerpt of some text
  45          *
  46          * @param string $text
  47          * @return string
  48          */
  49         private function excerpt( $text ) {
  50                 if ( strlen( $text ) > 20 ) {
  51                         $text = substr( $text, 0, 20 ) . '...';
  52                 }
  53                 return str_replace( "\n", "\\n", $text );
  54         }
  55
  56         /**
  57          * Get a readable version of the TreeBuilder preposition constants
  58          */
  59         private function getPrepositionName( $prep ) {
  60                 $names = [
  61                         TreeBuilder::BEFORE => 'before',
  62                         TreeBuilder::UNDER => 'under',
  63                         TreeBuilder::ROOT => 'under root'
  64                 ];
  65                 return isset( $names[$prep] ) ? $names[$prep] : '???';
  66         }
  67
  68         /**
  69          * A helper called before the underlying handler is called.
  70          */
  71         private function before() {
  72                 if ( $this->verbosity > 0 ) {
  73                         $this->trace( "Before: " . $this->handler->dump() . "\n" );
  74                 }
  75         }
  76
  77         /**
  78          * A helper called after the underlying handler is called.
  79          */
  80         private function after() {
  81                 if ( $this->verbosity > 0 ) {
  82                         $this->trace( "After:  " . $this->handler->dump() . "\n" );
  83                 }
  84         }
  85
  86         public function startDocument( $fns, $fn ) {
  87                 $this->trace( "startDocument" );
  88                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
  89         }
  90
  91         public function endDocument( $pos ) {
  92                 $this->trace( "endDocument $pos" );
  93                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
  94         }
  95
  96         public function characters( $preposition, $refNode, $text, $start, $length,
  97                 $sourceStart, $sourceLength
  98         ) {
  99                 $excerpt = $this->excerpt( substr( $text, $start, $length ) );
 100                 $prepName = $this->getPrepositionName( $preposition );
 101                 $refTag = $this->getDebugTag( $refNode );
 102
 103                 $this->trace( "characters \"$excerpt\", $prepName $refTag, start=$sourceStart" );
 104                 $this->before();
 105                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 106                 $this->after();
 107         }
 108
 109         public function insertElement( $preposition, $refNode, Element $element, $void,
 110                 $sourceStart, $sourceLength
 111         ) {
 112                 $prepName = $this->getPrepositionName( $preposition );
 113                 $refTag = $this->getDebugTag( $refNode );
 114                 $elementTag = $this->getDebugTag( $element );
 115                 $voidMsg = $void ? 'void' : '';
 116                 $this->trace( "insert $elementTag $voidMsg, $prepName $refTag, start=$sourceStart" );
 117                 $this->before();
 118                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 119                 $this->after();
 120         }
 121
 122         public function endTag( Element $element, $sourceStart, $sourceLength ) {
 123                 $elementTag = $this->getDebugTag( $element );
 124                 $this->trace( "end $elementTag, start=$sourceStart" );
 125                 $this->before();
 126                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 127                 $this->after();
 128         }
 129
 130         public function doctype( $name, $public, $system, $quirks, $sourceStart, $sourceLength ) {
 131                 $quirksTypes = [
 132                         TreeBuilder::QUIRKS => 'quirks',
 133                         TreeBuilder::NO_QUIRKS => 'no-quirks',
 134                         TreeBuilder::LIMITED_QUIRKS => 'limited-quirks'
 135                 ];
 136                 $quirksMsg = $quirksTypes[$quirks];
 137                 $this->trace( "doctype $name, public=\"$public\", system=\"$system\", " .
 138                         "$quirksMsg, start=$sourceStart" );
 139                 $this->before();
 140                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 141                 $this->after();
 142         }
 143
 144         public function comment( $preposition, $refNode, $text, $sourceStart, $sourceLength ) {
 145                 $prepName = $this->getPrepositionName( $preposition );
 146                 $refTag = $this->getDebugTag( $refNode );
 147                 $excerpt = $this->excerpt( $text );
 148
 149                 $this->trace( "comment \"$excerpt\", $prepName $refTag, start=$sourceStart" );
 150                 $this->before();
 151                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 152                 $this->after();
 153         }
 154
 155         public function error( $text, $pos ) {
 156                 $this->trace( "error \"$text\", start=$pos" );
 157                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 158         }
 159
 160         public function mergeAttributes( Element $element, Attributes $attrs, $sourceStart ) {
 161                 $elementTag = $this->getDebugTag( $element );
 162                 $this->trace( "merge $elementTag, start=$sourceStart" );
 163                 $this->before();
 164                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 165         }
 166
 167         public function removeNode( Element $element, $sourceStart ) {
 168                 $elementTag = $this->getDebugTag( $element );
 169                 $this->trace( "remove $elementTag, start=$sourceStart" );
 170                 $this->before();
 171                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 172                 $this->after();
 173         }
 174
 175         public function reparentChildren( Element $element, Element $newParent, $sourceStart ) {
 176                 $elementTag = $this->getDebugTag( $element );
 177                 $newParentTag = $this->getDebugTag( $newParent );
 178                 $this->trace( "reparent children of $elementTag under $newParentTag, start=$sourceStart" );
 179                 $this->before();
 180                 call_user_func_array( [ $this->handler, __FUNCTION__ ], func_get_args() );
 181                 $this->after();
 182         }
 183 }