Converted sort tests to non browserkit testing

Added testing to cover book sort endpoint.
Closes #283

tests/TestCase.php

@@ -1,8 +1,54 @@
 <?php namespace Tests;
 
+use BookStack\Book;
+use BookStack\Chapter;
+use BookStack\Repos\EntityRepo;
+use BookStack\Role;
 use Illuminate\Foundation\Testing\TestCase as BaseTestCase;
 
 abstract class TestCase extends BaseTestCase
 {
     use CreatesApplication;
+
+    protected $admin;
+
+    /**
+     * Set the current user context to be an admin.
+     * @return $this
+     */
+    public function asAdmin()
+    {
+        return $this->actingAs($this->getAdmin());
+    }
+
+    /**
+     * Get the current admin user.
+     * @return mixed
+     */
+    public function getAdmin() {
+        if($this->admin === null) {
+            $adminRole = Role::getSystemRole('admin');
+            $this->admin = $adminRole->users->first();
+        }
+        return $this->admin;
+    }
+
+    /**
+     * Create and return a new book.
+     * @param array $input
+     * @return Book
+     */
+    public function newBook($input = ['name' => 'test book', 'description' => 'My new test book']) {
+        return $this->app[EntityRepo::class]->createFromInput('book', $input, false);
+    }
+
+    /**
+     * Create and return a new test chapter
+     * @param array $input
+     * @param Book $book
+     * @return Chapter
+     */
+    public function newChapter($input = ['name' => 'test chapter', 'description' => 'My new test chapter'], Book $book) {
+        return $this->app[EntityRepo::class]->createFromInput('chapter', $input, $book);
+    }
 }