Fixes to billing routes

Author: gnikyt

src/ShopifyApp/Traits/BillingControllerTrait.php

@@ -21,14 +21,14 @@ trait BillingControllerTrait
     /**
      * Redirects to billing screen for Shopify.
      *
-     * @param \OhMyBrew\ShopifyApp\Models\Plan|null $plan The plan.
+     * @param \OhMyBrew\ShopifyApp\Models\Plan $plan The plan.
      *
      * @return \Illuminate\View\View
      */
-    public function index(Plan $plan = null)
+    public function index(Plan $plan)
     {
         // If the plan is null, get a plan
-        if (is_null($plan)) {
+        if (is_null($plan) || ($plan && !$plan->exists)) {
             $plan = Plan::where('on_install', true)->first();
         }
 

src/ShopifyApp/resources/routes.php

@@ -1,7 +1,5 @@
 <?php
 
-use OhMyBrew\ShopifyApp\Models\Plan;
-
 /*
 |--------------------------------------------------------------------------
 | Web Routes

tests/Controllers/BillingControllerTest.php

@@ -16,7 +16,7 @@ class BillingControllerTest extends TestCase
     public function setUp()
     {
         parent::setUp();
-
+        ;$this->withoutExceptionHandling();
         // Stub in our API class
         Config::set('shopify-app.api_class', new ApiStub());
 
@@ -36,6 +36,9 @@ public function testSendsShopToBillingScreen()
         $shop = factory(Shop::class)->create();
         Session::put('shopify_domain', $shop->shopify_domain);
 
+        // Create a on-install plan
+        factory(Plan::class)->states('type_recurring', 'installable')->create();
+
         // Run the call
         $response = $this->get('/billing');
         $response->assertViewHas(