MDL-44357 theme: Allow core to compile LESS in PHP

lib/lessphp/VisitorReplacing.php

@@ -0,0 +1,75 @@
+<?php
+
+/**
+ * Replacing Visitor
+ *
+ * @package Less
+ * @subpackage visitor
+ */
+class Less_VisitorReplacing extends Less_Visitor{
+
+	function visitObj( $node ){
+
+		$funcName = 'visit'.$node->type;
+		if( isset($this->_visitFnCache[$funcName]) ){
+
+			$visitDeeper = true;
+			$node = $this->$funcName( $node, $visitDeeper );
+
+			if( $node ){
+				if( $visitDeeper && is_object($node) ){
+					$node->accept($this);
+				}
+
+				$funcName = $funcName . "Out";
+				if( isset($this->_visitFnCache[$funcName]) ){
+					$this->$funcName( $node );
+				}
+			}
+
+		}else{
+			$node->accept($this);
+		}
+
+		return $node;
+	}
+
+	function visitArray( $nodes ){
+
+		$newNodes = array();
+		foreach($nodes as $node){
+			$evald = $this->visitObj($node);
+			if( $evald ){
+				if( is_array($evald) ){
+					self::flatten($evald,$newNodes);
+				}else{
+					$newNodes[] = $evald;
+				}
+			}
+		}
+		return $newNodes;
+	}
+
+	function flatten( $arr, &$out ){
+
+		foreach($arr as $item){
+			if( !is_array($item) ){
+				$out[] = $item;
+				continue;
+			}
+
+			foreach($item as $nestedItem){
+				if( is_array($nestedItem) ){
+					self::flatten( $nestedItem, $out);
+				}else{
+					$out[] = $nestedItem;
+				}
+			}
+		}
+
+		return $out;
+	}
+
+}
+
+