[9.x] Introduce a fake() helper to resolve faker singletons, per locale

src/Illuminate/Foundation/helpers.php

@@ -451,6 +451,27 @@ function event(...$args)
     }
 }
 
+if (! function_exists('fake') && class_exists(\Faker\Factory::class)) {
+    /**
+     * Get a faker instance.
+     *
+     * @param  ?string  $locale
+     * @return \Faker\Generator
+     */
+    function fake($locale = null)
+    {
+        $locale ??= app('config')->get('app.faker_locale') ?? 'en_US';
+
+        $abstract = \Faker\Generator::class.':'.$locale;
+
+        if (! app()->bound($abstract)) {
+            app()->singleton($abstract, fn () => \Faker\Factory::create($locale));
+        }
+
+        return app()->make($abstract);
+    }
+}
+
 if (! function_exists('info')) {
     /**
      * Write some information to the log.

tests/Foundation/FoundationHelpersTest.php

@@ -3,6 +3,7 @@
 namespace Illuminate\Tests\Foundation;
 
 use Exception;
+use Illuminate\Config\Repository as ConfigRepository;
 use Illuminate\Contracts\Config\Repository;
 use Illuminate\Foundation\Application;
 use Illuminate\Foundation\Mix;
@@ -244,4 +245,33 @@ public function testMixIsSwappableForTests()
 
         $this->assertSame('expected', mix('asset.png'));
     }
+
+    public function testFakeReturnsSameInstance()
+    {
+        app()->instance('config', new ConfigRepository([]));
+
+        $this->assertSame(fake(), fake());
+        $this->assertSame(fake(), fake('en_US'));
+        $this->assertSame(fake('en_AU'), fake('en_AU'));
+        $this->assertNotSame(fake('en_US'), fake('en_AU'));
+
+        app()->flush();
+    }
+
+    public function testFakeUsesLocale()
+    {
+        mt_srand(12345, MT_RAND_PHP);
+        app()->instance('config', new ConfigRepository([]));
+
+        // Should fallback to en_US
+        $this->assertSame('Arkansas', fake()->state());
+        $this->assertSame('Australian Capital Territory', fake('en_AU')->state());
+        $this->assertSame('Guadeloupe', fake('fr_FR')->region());
+
+        app()->instance('config', new ConfigRepository(['app' => ['faker_locale' => 'en_AU']]));
+        mt_srand(4, MT_RAND_PHP);
+
+        // Should fallback to en_US
+        $this->assertSame('Australian Capital Territory', fake()->state());
+    }
 }