filter iterator

src/Iterator/Filter.php

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Dakujem\Oliva\Iterator;
+
+use CallbackFilterIterator;
+
+/**
+ * Filter tree iterator.
+ * To be used with tree traversal iterators or for filtering input data.
+ *
+ * Wraps the native callback filter iterator with improved interface (supporting arrays).
+ *
+ * @author Andrej Rypak <[email protected]>
+ */
+final class Filter extends CallbackFilterIterator
+{
+    /**
+     * @param callable $accept Callable predicate returning `true`/truthy for accepted nodes; signature: `fn(TreeNodeContract|mixed):bool`
+     */
+    public function __construct(
+        iterable $input,
+        callable $accept,
+    ) {
+        parent::__construct(
+            Data::iterator($input),
+            $accept,
+        );
+    }
+}

tests/mptree.phpt

@@ -57,6 +57,9 @@ foreach($it as $key => $node){
 
 //xdebug_break();
 
+new Filter($it, Data::omitNull());
+new Filter($it, Data::omitRoot());
+
 $item = $tree->root()?->data();