use proper keys to not override appended files

Author: xabbuh

Finder.php

@@ -669,7 +669,8 @@ public function append($iterator)
         } elseif ($iterator instanceof \Traversable || \is_array($iterator)) {
             $it = new \ArrayIterator();
             foreach ($iterator as $file) {
-                $it->append($file instanceof \SplFileInfo ? $file : new \SplFileInfo($file));
+                $file = $file instanceof \SplFileInfo ? $file : new \SplFileInfo($file);
+                $it[$file->getPathname()] = $file;
             }
             $this->iterators[] = $it;
         } else {

Tests/FinderTest.php

@@ -1119,6 +1119,17 @@ public function testAppendDoesNotRequireIn()
         $this->assertIterator(iterator_to_array($finder->getIterator()), $finder1->getIterator());
     }
 
+    public function testMultipleAppendCallsWithSorting()
+    {
+        $finder = $this->buildFinder()
+            ->sortByName()
+            ->append([self::$tmpDir.\DIRECTORY_SEPARATOR.'qux_1000_1.php'])
+            ->append([self::$tmpDir.\DIRECTORY_SEPARATOR.'qux_1002_0.php'])
+        ;
+
+        $this->assertOrderedIterator($this->toAbsolute(['qux_1000_1.php', 'qux_1002_0.php']), $finder->getIterator());
+    }
+
     public function testCountDirectories()
     {
         $directory = Finder::create()->directories()->in(self::$tmpDir);