Fix the RateLimite issue when generating dynamic keys

src/Illuminate/Cache/RateLimiter.php

@@ -85,7 +85,9 @@ public function limiter($name)
 
             foreach ($result as $limit) {
                 if ($duplicates->contains($limit->key)) {
-                    $limit->key = $limit->fallbackKey();
+                    $limit->key = empty($limit->key)
+                        ? $limit->fallbackKey()
+                        : $limit->key.':'.$limit->fallbackKey();
                 }
             }
 

tests/Cache/RateLimiterTest.php

@@ -2,8 +2,10 @@
 
 namespace Illuminate\Tests\Cache;
 
+use Illuminate\Cache\ArrayStore;
 use Illuminate\Cache\RateLimiter;
 use Illuminate\Cache\RateLimiting\Limit;
+use Illuminate\Cache\Repository;
 use Illuminate\Contracts\Cache\Repository as Cache;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
@@ -38,6 +40,33 @@ public function testRegisterNamedRateLimiter(mixed $name, string $expected): voi
 
         $this->assertNotNull($limiterClosure);
     }
+
+    public function testShouldUseOriginKeyAsPrefixWhenMultipleLimiterWithSameKey()
+    {
+        $rateLimiter = new RateLimiter(new Repository(new ArrayStore));
+
+        $rateLimiter->for('user_limiter1', fn (string $userId) => [
+            Limit::perSecond(3)->by($userId),
+            Limit::perMinute(5)->by($userId),
+        ]);
+
+        $userId1 = '123';
+        $userId2 = '456';
+
+        $userLimiters1 = $rateLimiter->limiter('user_limiter1')($userId1);
+        $userLimiters2 = $rateLimiter->limiter('user_limiter1')($userId2);
+
+        for ($i = 0; $i < 3; $i++) {
+            $this->assertFalse($rateLimiter->tooManyAttempts($userLimiters1[0]->key, $userLimiters1[0]->maxAttempts));
+            $this->assertFalse($rateLimiter->tooManyAttempts($userLimiters2[0]->key, $userLimiters2[0]->maxAttempts));
+
+            $rateLimiter->hit($userLimiters1[0]->key, $userLimiters1[0]->decaySeconds);
+            $rateLimiter->hit($userLimiters2[0]->key, $userLimiters2[0]->decaySeconds);
+        }
+
+        $this->assertNotSame($userLimiters1[0]->key, $userLimiters2[0]->key);
+        $this->assertNotSame($userLimiters1[1]->key, $userLimiters2[1]->key);
+    }
 }
 
 enum BackedEnumNamedRateLimiter: string