Add NodeInterface::all(), NodeInterface::find() and NodeInterface::de…

…lete().

spec/drupol/phptree/Node/NodeSpec.php

@@ -60,6 +60,52 @@ public function it_can_count_its_children()
             ->shouldReturn(1);
     }
 
+    public function it_can_delete()
+    {
+        $node1 = new Node();
+        $node2 = new Node();
+        $node3 = new Node();
+        $node4 = new Node();
+        $node3->add($node4);
+
+        $this
+            ->add($node1, $node2, $node3);
+
+        $this
+            ->count()
+            ->shouldReturn(4);
+
+        $this
+            ->delete($node2)
+            ->shouldReturn($node2->setParent(null));
+
+        $this
+            ->degree()
+            ->shouldReturn(2);
+
+        $this
+            ->count()
+            ->shouldReturn(3);
+
+        $this
+            ->delete($node3)
+            ->shouldReturn($node3->setParent(null));
+
+        $this
+            ->degree()
+            ->shouldReturn(1);
+
+        $node5 = new Node();
+
+        $this
+            ->delete($node5)
+            ->shouldReturn(null);
+
+        $this
+            ->shouldThrow(\InvalidArgumentException::class)
+            ->during('delete', [$this]);
+    }
+
     public function it_can_get_and_set_the_parent(NodeInterface $parent)
     {
         $this
@@ -278,7 +324,7 @@ public function it_is_a_traversable()
         $this
             ->add($node1, $node2, $node3);
 
-        $this->shouldIterateLike($this->children());
+        $this->shouldIterateLike($this->all());
     }
 
     public function it_is_initializable()

src/Node/Node.php

@@ -44,6 +44,18 @@ public function add(NodeInterface ...$nodes): NodeInterface
         return $this;
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function all(): \Traversable
+    {
+        yield $this;
+
+        foreach ($this->children() as $candidate) {
+            yield from $candidate->all();
+        }
+    }
+
     /**
      * {@inheritdoc}
      *
@@ -59,11 +71,10 @@ public function children(): \Traversable
      */
     public function count(): int
     {
-        $count = 0;
+        $count = -1;
 
-        /** @var \drupol\phptree\Node\NodeInterface $child */
-        foreach ($this->children() as $child) {
-            $count += 1 + $child->count();
+        foreach ($this->all() as $node) {
+            ++$count;
         }
 
         return $count;
@@ -77,6 +88,28 @@ public function degree(): int
         return $this->storage()->getChildren()->count();
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function delete(NodeInterface $node, NodeInterface $root = null): ?NodeInterface
+    {
+        $root = $root ?? $this;
+
+        if ($candidate = $this->find($node)) {
+            if ($candidate === $root) {
+                throw new \InvalidArgumentException('Unable to delete root node.');
+            }
+
+            if (null !== $parent = $candidate->getParent()) {
+                $parent->remove($node);
+            }
+
+            return $candidate->setParent(null);
+        }
+
+        return null;
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -85,6 +118,20 @@ public function depth(): int
         return \iterator_count($this->getAncestors());
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function find(NodeInterface $node): ?NodeInterface
+    {
+        foreach ($this->all() as $candidate) {
+            if ($candidate === $node) {
+                return $node;
+            }
+        }
+
+        return null;
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -102,7 +149,7 @@ public function getAncestors(): \Traversable
      */
     public function getIterator()
     {
-        yield from $this->children();
+        yield from $this->all();
     }
 
     /**
@@ -185,7 +232,9 @@ public function offsetGet($offset)
     public function offsetSet($offset, $value)
     {
         if (!($value instanceof NodeInterface)) {
-            throw new \InvalidArgumentException('The value must implements NodeInterface.');
+            throw new \InvalidArgumentException(
+                'The value must implements NodeInterface.'
+            );
         }
 
         $this->storage()->getChildren()
@@ -220,7 +269,7 @@ static function ($child) use ($nodes) {
     /**
      * {@inheritdoc}
      */
-    public function setParent(NodeInterface $node = null): NodeInterface
+    public function setParent(?NodeInterface $node): NodeInterface
     {
         $this->storage()->setParent($node);
 

src/Node/NodeInterface.php

@@ -20,10 +20,18 @@ interface NodeInterface extends \Countable, \ArrayAccess, \Traversable, \Iterato
      */
     public function add(NodeInterface ...$node): NodeInterface;
 
+    /**
+     * Get all the nodes of a tree including the parent node itself.
+     *
+     * @return \drupol\phptree\Node\NodeInterface|\Traversable
+     *   The node.
+     */
+    public function all(): \Traversable;
+
     /**
      * Get the children.
      *
-     * @return \Traversable
+     * @return \drupol\phptree\Node\NodeInterface|\Traversable
      *   The children
      */
     public function children(): \Traversable;
@@ -36,6 +44,17 @@ public function children(): \Traversable;
      */
     public function degree(): int;
 
+    /**
+     * Remove a node (and its subnodes) from a tree.
+     *
+     * @param \drupol\phptree\Node\NodeInterface $node
+     *   The node to remove.
+     *
+     * @return null|\drupol\phptree\Node\NodeInterface
+     *   The node that has been removed without parent, null otherwise.
+     */
+    public function delete(NodeInterface $node): ?NodeInterface;
+
     /**
      * Get the node depth from the root node.
      *
@@ -44,6 +63,17 @@ public function degree(): int;
      */
     public function depth(): int;
 
+    /**
+     * Check if a node is find is in the tree.
+     *
+     * @param \drupol\phptree\Node\NodeInterface $node
+     *   The node to find.
+     *
+     * @return null|\drupol\phptree\Node\NodeInterface
+     *   The node if found, false otherwise.
+     */
+    public function find(NodeInterface $node): ?NodeInterface;
+
     /**
      * Get the ancestors of a node.
      *
@@ -106,13 +136,13 @@ public function remove(NodeInterface ...$node): NodeInterface;
     /**
      * Set the parent.
      *
-     * @param NodeInterface $node
+     * @param null|NodeInterface $node
      *   The parent node
      *
      * @return NodeInterface
      *   The node
      */
-    public function setParent(NodeInterface $node = null): NodeInterface;
+    public function setParent(?NodeInterface $node): NodeInterface;
 
     /**
      * Get a clone of the object with or without children.