Update for coupons

src/SubscriptionBuilder.php

@@ -64,6 +64,13 @@ class SubscriptionBuilder
      */
     protected $coupon;
 
+    /**
+     * Determines if user redeemable promotion codes are available in Stripe Checkout.
+     *
+     * @var bool
+     */
+    protected $allowPromotionCodes = false;
+
     /**
      * The metadata to apply to the subscription.
      *
@@ -200,6 +207,18 @@ public function withCoupon($coupon)
         return $this;
     }
 
+    /**
+     * Enables user redeemable promotion codes.
+     *
+     * @return $this
+     */
+    public function allowPromotionCodes()
+    {
+        $this->allowPromotionCodes = true;
+
+        return $this;
+    }
+
     /**
      * The metadata to apply to a new subscription.
      *
@@ -312,9 +331,12 @@ public function checkout(array $sessionOptions = [], array $customerOptions = []
         return Checkout::create($this->owner, array_merge([
             'mode' => 'subscription',
             'line_items' => collect($this->items)->values()->all(),
+            'allow_promotion_codes' => $this->allowPromotionCodes,
+            'discounts' => [
+                'coupon' => $this->coupon,
+            ],
             'default_tax_rates' => $this->getTaxRatesForPayload(),
             'subscription_data' => [
-                'coupon' => $this->coupon,
                 'trial_end' => $trialEnd ? $trialEnd->getTimestamp() : null,
                 'metadata' => array_merge($this->metadata, ['name' => $this->name]),
             ],

tests/Feature/CheckoutTest.php

@@ -56,12 +56,15 @@ public function test_customers_can_start_a_subscription_checkout_session()
             'unit_amount' => 1500,
         ]);
 
-        $checkout = $user->newSubscription('default', $price->id)->checkout([
-            'success_url' => 'http://example.com',
-            'cancel_url' => 'http://example.com',
-        ]);
+        $checkout = $user->newSubscription('default', $price->id)
+            ->allowPromotionCodes()
+            ->checkout([
+                'success_url' => 'http://example.com',
+                'cancel_url' => 'http://example.com',
+            ]);
 
         $this->assertInstanceOf(Checkout::class, $checkout);
-        $this->assertInstanceOf(StripeCheckoutSession::class, $checkout->asStripeCheckoutSession());
+        $this->assertInstanceOf(StripeCheckoutSession::class, $session = $checkout->asStripeCheckoutSession());
+        $this->assertTrue($session->allow_promotion_codes);
     }
 }