Fixed #73, Creator forgets namespaces

src/FluentDOM/Element.php

@@ -185,9 +185,9 @@ public function append($value) {
             ? $value : $this->ownerDocument->importNode($value)
         );
       } elseif ($value instanceof Appendable) {
-        $namespaces = $this->ownerDocument->namespaces();
+        $this->ownerDocument->namespaces()->stash();
         $value->appendTo($this);
-        $this->ownerDocument->namespaces($namespaces);
+        $this->ownerDocument->namespaces()->unstash();
       } elseif ($value instanceof \Closure && !$value instanceof \DOMNode) {
         $this->append($value());
       } elseif (is_array($value)) {

src/FluentDOM/Namespaces.php

@@ -17,6 +17,11 @@ class Namespaces implements NamespaceResolver, \ArrayAccess, \IteratorAggregate,
       'xmlns' => 'http://www.w3.org/2000/xmlns/'
     ];
 
+    /**
+     * @var array
+     */
+    private $_stash = [];
+
     /**
      * Namespaces constructor.
      * @param NULL|array|\Traversable $namespaces
@@ -101,6 +106,20 @@ public function getIterator() {
       return new \ArrayIterator($this->_namespaces);
     }
 
+    /**
+     * Store current status on the stash
+     */
+    public function stash() {
+      $this->_stash[] = $this->_namespaces;
+    }
+
+    /**
+     * Restore last stashed status from the stash
+     */
+    public function unstash() {
+      $this->_namespaces = array_pop($this->_stash);
+    }
+
     /**
      * @return int
      */

tests/FluentDOM/Issues/73Test.php

@@ -0,0 +1,42 @@
+<?php
+namespace FluentDOM {
+
+  use FluentDOM\Nodes\Creator;
+
+  require_once(__DIR__.'/../TestCase.php');
+
+  class Issue73Test extends TestCase {
+
+    public function testCreatorDoesNotForgetNamespaces() {
+      $_ = new Creator();
+      $_->registerNamespace('atom', 'urn:atom');
+      $result = $_(
+        'atom:feed',
+        $_->each(
+          [1, 2, 3],
+          function($number) use ($_) {
+            return $_(
+              'atom:entry',
+              $_('atom:title', $number)
+            );
+          }
+        )
+      )->getDocument();
+      $this->assertXmlStringEqualsXmlString(
+        '<?xml version="1.0"?>
+          <atom:feed xmlns:atom="urn:atom">
+            <atom:entry>
+              <atom:title>1</atom:title>
+            </atom:entry>
+            <atom:entry>
+              <atom:title>2</atom:title>
+            </atom:entry>
+            <atom:entry>
+              <atom:title>3</atom:title>
+            </atom:entry>
+          </atom:feed>',
+        (string)$result->saveXML()
+      );
+    }
+  }
+}