NotificationFake can assert preferred locale (#26205)

When a notifiable implements the HasLocalePreference
interface, make the NotificationFake store the locale
for assertions.

Add a similar feature test for MailFake that already
supports the same assertion capabilities.

src/Illuminate/Support/Testing/Fakes/NotificationFake.php

@@ -5,6 +5,7 @@
 use Illuminate\Support\Str;
 use Illuminate\Support\Collection;
 use PHPUnit\Framework\Assert as PHPUnit;
+use Illuminate\Contracts\Translation\HasLocalePreference;
 use Illuminate\Contracts\Notifications\Factory as NotificationFactory;
 use Illuminate\Contracts\Notifications\Dispatcher as NotificationDispatcher;
 
@@ -210,7 +211,11 @@ public function sendNow($notifiables, $notification)
                 'notification' => $notification,
                 'channels' => $notification->via($notifiable),
                 'notifiable' => $notifiable,
-                'locale' => $notification->locale ?? $this->locale,
+                'locale' => $notification->locale ?? $this->locale ?? value(function () use ($notifiable) {
+                    if ($notifiable instanceof HasLocalePreference) {
+                        return $notifiable->preferredLocale();
+                    }
+                }),
             ];
         }
     }

tests/Support/SupportTestingMailFakeTest.php

@@ -8,6 +8,7 @@
 use Illuminate\Support\Testing\Fakes\MailFake;
 use PHPUnit\Framework\ExpectationFailedException;
 use PHPUnit\Framework\Constraint\ExceptionMessage;
+use Illuminate\Contracts\Translation\HasLocalePreference;
 
 class SupportTestingMailFakeTest extends TestCase
 {
@@ -42,6 +43,17 @@ public function testAssertSent()
         $this->fake->assertSent(MailableStub::class);
     }
 
+    public function testAssertSentWhenRecipientHasPreferredLocale()
+    {
+        $user = new LocalizedRecipientStub;
+
+        $this->fake->to($user)->send($this->mailable);
+
+        $this->fake->assertSent(MailableStub::class, function ($mail) use ($user) {
+            return $mail->hasTo($user) && $mail->locale === 'au';
+        });
+    }
+
     public function testAssertNotSent()
     {
         $this->fake->assertNotSent(MailableStub::class);
@@ -164,3 +176,13 @@ public function build()
              ->withLastName('Otwell');
     }
 }
+
+class LocalizedRecipientStub implements HasLocalePreference
+{
+    public $email = '[email protected]';
+
+    public function preferredLocale()
+    {
+        return 'au';
+    }
+}

tests/Support/SupportTestingNotificationFakeTest.php

@@ -8,6 +8,7 @@
 use PHPUnit\Framework\ExpectationFailedException;
 use PHPUnit\Framework\Constraint\ExceptionMessage;
 use Illuminate\Support\Testing\Fakes\NotificationFake;
+use Illuminate\Contracts\Translation\HasLocalePreference;
 
 class SupportTestingNotificationFakeTest extends TestCase
 {
@@ -94,6 +95,17 @@ public function testAssertTimesSent()
 
         $this->fake->assertTimesSent(3, NotificationStub::class);
     }
+
+    public function testAssertSentToWhenNotifiableHasPreferredLocale()
+    {
+        $user = new LocalizedUserStub;
+
+        $this->fake->send($user, new NotificationStub);
+
+        $this->fake->assertSentTo($user, NotificationStub::class, function ($notification, $channels, $notifiable, $locale) use ($user) {
+            return $notifiable === $user && $locale === 'au';
+        });
+    }
 }
 
 class NotificationStub extends Notification
@@ -108,3 +120,11 @@ class UserStub extends User
 {
     //
 }
+
+class LocalizedUserStub extends User implements HasLocalePreference
+{
+    public function preferredLocale()
+    {
+        return 'au';
+    }
+}