[COMPOSER] Add new php-ffmpeg package

vendor/nikic/php-parser/lib/PhpParser/NodeTraverser.php

@@ -0,0 +1,156 @@
+<?php
+
+namespace PhpParser;
+
+class NodeTraverser implements NodeTraverserInterface
+{
+    /**
+     * @var NodeVisitor[] Visitors
+     */
+    protected $visitors;
+
+    /**
+     * @var bool
+     */
+    private $cloneNodes;
+
+    /**
+     * Constructs a node traverser.
+     *
+     * @param bool $cloneNodes Should the traverser clone the nodes when traversing the AST
+     */
+    public function __construct($cloneNodes = true) {
+        $this->visitors = array();
+        $this->cloneNodes = $cloneNodes;
+    }
+
+    /**
+     * Adds a visitor.
+     *
+     * @param NodeVisitor $visitor Visitor to add
+     */
+    public function addVisitor(NodeVisitor $visitor) {
+        $this->visitors[] = $visitor;
+    }
+
+    /**
+     * Removes an added visitor.
+     *
+     * @param NodeVisitor $visitor
+     */
+    public function removeVisitor(NodeVisitor $visitor) {
+        foreach ($this->visitors as $index => $storedVisitor) {
+            if ($storedVisitor === $visitor) {
+                unset($this->visitors[$index]);
+                break;
+            }
+        }
+    }
+
+    /**
+     * Traverses an array of nodes using the registered visitors.
+     *
+     * @param Node[] $nodes Array of nodes
+     *
+     * @return Node[] Traversed array of nodes
+     */
+    public function traverse(array $nodes) {
+        foreach ($this->visitors as $visitor) {
+            if (null !== $return = $visitor->beforeTraverse($nodes)) {
+                $nodes = $return;
+            }
+        }
+
+        $nodes = $this->traverseArray($nodes);
+
+        foreach ($this->visitors as $visitor) {
+            if (null !== $return = $visitor->afterTraverse($nodes)) {
+                $nodes = $return;
+            }
+        }
+
+        return $nodes;
+    }
+
+    protected function traverseNode(Node $node) {
+        if ($this->cloneNodes) {
+            $node = clone $node;
+        }
+
+        foreach ($node->getSubNodeNames() as $name) {
+            $subNode =& $node->$name;
+
+            if (is_array($subNode)) {
+                $subNode = $this->traverseArray($subNode);
+            } elseif ($subNode instanceof Node) {
+                $traverseChildren = true;
+                foreach ($this->visitors as $visitor) {
+                    $return = $visitor->enterNode($subNode);
+                    if (self::DONT_TRAVERSE_CHILDREN === $return) {
+                        $traverseChildren = false;
+                    } else if (null !== $return) {
+                        $subNode = $return;
+                    }
+                }
+
+                if ($traverseChildren) {
+                    $subNode = $this->traverseNode($subNode);
+                }
+
+                foreach ($this->visitors as $visitor) {
+                    if (null !== $return = $visitor->leaveNode($subNode)) {
+                        $subNode = $return;
+                    }
+                }
+            }
+        }
+
+        return $node;
+    }
+
+    protected function traverseArray(array $nodes) {
+        $doNodes = array();
+
+        foreach ($nodes as $i => &$node) {
+            if (is_array($node)) {
+                $node = $this->traverseArray($node);
+            } elseif ($node instanceof Node) {
+                $traverseChildren = true;
+                foreach ($this->visitors as $visitor) {
+                    $return = $visitor->enterNode($node);
+                    if (self::DONT_TRAVERSE_CHILDREN === $return) {
+                        $traverseChildren = false;
+                    } else if (null !== $return) {
+                        $node = $return;
+                    }
+                }
+
+                if ($traverseChildren) {
+                    $node = $this->traverseNode($node);
+                }
+
+                foreach ($this->visitors as $visitor) {
+                    $return = $visitor->leaveNode($node);
+
+                    if (self::REMOVE_NODE === $return) {
+                        $doNodes[] = array($i, array());
+                        break;
+                    } elseif (is_array($return)) {
+                        $doNodes[] = array($i, $return);
+                        break;
+                    } elseif (null !== $return) {
+                        $node = $return;
+                    }
+                }
+            }
+        }
+
+        if (!empty($doNodes)) {
+            while (list($i, $replace) = array_pop($doNodes)) {
+                array_splice($nodes, $i, 1, $replace);
+            }
+        }
+
+        return $nodes;
+    }
+}