Make existing page detection aware of ParentID

The existing logic moved existing pages around into the imported
structure if they were matching the same title.

code/SiteTreeImporter.php

@@ -89,17 +89,20 @@ function bulkimport($data, $form) {
 				// Allow custom classes based on meta data
 				$className = (array_key_exists('ClassName', $json)) ? $json['ClassName'] : 'Page';
 
-				// Try to find an existing page, or create a new one
-				$page = Page::get()->find('URLSegment', $url);
-				if(!$page) $page = new $className();
-
 				// If we've got too many tabs, then outdent until we find a page to attach to.
 				while(!isset($parentRefs[$numTabs-1]) && $numTabs > 0) $numTabs--;
 
-				// Set parent based on parentRefs;
-				if($numTabs > 0) $page->ParentID = $parentRefs[$numTabs-1];
+				$parentID = ($numTabs > 0) ? $parentRefs[$numTabs-1] : 0;
+
+				// Try to find an existing page, or create a new one
+				$page = Page::get()->filter(array(
+					'URLSegment' => $url,
+					'ParentID' => $parentID
+				))->First();
+				if(!$page) $page = new $className();
 
 				// Apply any meta data properties to the page
+				$page->ParentID = $parentID;
 				$page->Title = $title;
 				$page->URLSegment = $url;
 				if($json) $page->update($json);

tests/SiteTreeImporterTest.php

@@ -120,6 +120,33 @@ function testImportWithJSON() {
 		$this->assertEquals($child2_2->ClassName, 'SiteTreeImporterTest_TestPage');
 	}
 
+	function testDetectsDuplicatesByParent() {
+		$page = new Page();
+		$page->Title = 'MyPage';
+		$page->URLSegment = 'mypage';
+		$page->write();
+		$page->publish('Stage', 'Live');
+
+		// Import page with same name but a different hierarchy
+		$data = <<<YML
+Parent
+	MyPage
+YML;
+		$this->import($data);
+
+		$pages = Page::get()->filter('Title', 'MyPage')->sort('Created');
+
+		$existingPage = $pages->filter('ID', $page->ID)->First();
+		$this->assertNotNull($existingPage);
+		$this->assertEquals($existingPage->Title, 'MyPage');
+		$this->assertEquals((int)$existingPage->ParentID, (int)$page->ParentID);
+
+		$newPage = $pages->exclude('ID', $page->ID)->First();
+		$this->assertNotNull($newPage);
+		$this->assertEquals($newPage->Title, 'MyPage');
+		$this->assertNotEquals((int)$newPage->ParentID, (int)$page->ParentID);
+	}
+
 	protected function import($yml, $data = null) {
 		$data = $data ? $data : array();
 		$data['SourceFile'] = array();