From 772198a7fc4dd289bc1e5fab7238df60145e49b4 Mon Sep 17 00:00:00 2001
From: Robbie Averill <robbie@silverstripe.com>
Date: Thu, 8 Jun 2017 12:26:53 +1200
Subject: [PATCH] FIX Backlink for upload form redirects to document admin if
 no page is available

---
 code/cms/DMSDocumentAddController.php      | 14 ++++++++++++--
 tests/cms/DMSDocumentAddControllerTest.php |  8 ++++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/code/cms/DMSDocumentAddController.php b/code/cms/DMSDocumentAddController.php
index 0fc11f0..93e95bd 100644
--- a/code/cms/DMSDocumentAddController.php
+++ b/code/cms/DMSDocumentAddController.php
@@ -187,11 +187,21 @@ class DMSDocumentAddController extends LeftAndMain
      */
     public function Backlink()
     {
-        if (!$this->getRequest()->getVar('dsid')) {
+        if (!$this->getRequest()->getVar('dsid') || !$this->currentPageID()) {
             $modelAdmin = new DMSDocumentAdmin;
             $modelAdmin->init();
-            return $modelAdmin->Link();
+
+            if ($this->getRequest()->getVar('dsid')) {
+                return Controller::join_links(
+                    $modelAdmin->Link('DMSDocumentSet'),
+                    'EditForm/field/DMSDocumentSet/item',
+                    $this->getRequest()->getVar('dsid'),
+                    'edit'
+                );
+            }
+            return $modelAdmin->Link('DMSDocumentSet');
         }
+
         return Controller::join_links(
             singleton('CMSPagesController')->Link(),
             'edit/EditForm/field/Document%20Sets/item',
diff --git a/tests/cms/DMSDocumentAddControllerTest.php b/tests/cms/DMSDocumentAddControllerTest.php
index f77e9da..e07f85f 100644
--- a/tests/cms/DMSDocumentAddControllerTest.php
+++ b/tests/cms/DMSDocumentAddControllerTest.php
@@ -64,12 +64,20 @@ class DMSDocumentAddControllerTest extends FunctionalTest
      */
     public function testBacklink()
     {
+        // No page ID and no document set ID
         $this->assertContains('admin/documents', $this->controller->Backlink());
 
+        // No page ID, has document set ID
         $request = new SS_HTTPRequest('GET', '/', array('dsid' => 123));
         $this->controller->setRequest($request);
         $this->assertContains('EditForm', $this->controller->Backlink());
         $this->assertContains('123', $this->controller->Backlink());
+
+        // Has page ID and document set ID
+        $request = new SS_HTTPRequest('GET', '/', array('dsid' => 123, 'ID' => 234));
+        $this->controller->setRequest($request);
+        $this->assertContains('admin/pages', $this->controller->Backlink());
+        $this->assertContains('123', $this->controller->Backlink());
     }
 
     /**