Remove no longer used methods.

Author: drupol

spec/drupol/phptree/Node/NodeSpec.php

@@ -98,20 +98,6 @@ public function it_can_get_its_children()
             ->shouldYield(new \ArrayIterator([$node, $node]));
     }
 
-    public function it_can_get_the_last_children()
-    {
-        $this
-            ->lastChild()
-            ->shouldReturn(null);
-
-        $node = new Node();
-
-        $this
-            ->add($node)
-            ->lastChild()
-            ->shouldReturn($node);
-    }
-
     public function it_can_check_if_its_a_leaf()
     {
         $this

src/Node/Node.php

@@ -86,14 +86,6 @@ public function children(): \Traversable
         yield from $this->storage['children'];
     }
 
-    /**
-     * {@inheritdoc}
-     */
-    public function lastChild(): ?NodeInterface
-    {
-        return $this->storage['children'][$this->storage['children']->count() - 1] ?? null;
-    }
-
     /**
      * {@inheritdoc}
      */

src/Node/NodeInterface.php

@@ -116,12 +116,4 @@ public function depth(): int;
      *   The new object.
      */
     public function withChildren(NodeInterface ...$nodes): NodeInterface;
-
-    /**
-     * Get the last child if any.
-     *
-     * @return \drupol\phptree\Node\NodeInterface|null
-     *   The last child if any, null otherwise.
-     */
-    public function lastChild(): ?NodeInterface;
 }