fix: Align query parameters behavior between PSR-7 and Yii2 Request.

src/adapter/ServerRequestAdapter.php

@@ -48,6 +48,13 @@
  */
 final class ServerRequestAdapter
 {
+    /**
+     * Query parameters resolved from the PSR-7 ServerRequestInterface.
+     *
+     * @phpstan-var array<array-key, mixed>
+     */
+    private array $queryParams = [];
+
     /**
      * Creates a new instance of the {@see ServerRequestAdapter} class.
      *
@@ -83,7 +90,6 @@ public function getBodyParams(string $methodParam): array|object
     {
         $parsedBody = $this->psrRequest->getParsedBody();
 
-        // remove method parameter if present (same logic as parent)
         if (is_array($parsedBody) && isset($parsedBody[$methodParam])) {
             $bodyParams = $parsedBody;
 
@@ -219,14 +225,17 @@ public function getParsedBody(): array|object|null
     }
 
     /**
-     * Retrieves query parameters from the PSR-7 ServerRequestInterface.
+     * Retrieves query parameters from the PSR-7 ServerRequestInterface or cached values.
      *
-     * Returns the query parameters as an associative array, providing direct access to all values present in the
-     * request URI.
+     * Returns the cached query parameters if previously set, otherwise retrieves them directly from the PSR-7
+     * ServerRequestInterface instance.
      *
-     * @return array Associative array of query parameters from the request URI.
+     * This method provides immutable, type-safe access to query parameters for use in Yii2 Request component logic and
+     * controller actions.
      *
-     * @phpstan-return array<mixed, mixed>
+     * @return array Query parameters as an associative array.
+     *
+     * @phpstan-return array<array-key, mixed>
      *
      * Usage example:
      * ```php
@@ -235,6 +244,10 @@ public function getParsedBody(): array|object|null
      */
     public function getQueryParams(): array
     {
+        if ($this->queryParams !== []) {
+            return $this->queryParams;
+        }
+
         return $this->psrRequest->getQueryParams();
     }
 
@@ -395,9 +408,9 @@ public function resolve(Request $request): array
         if ($result !== false) {
             [$route, $params] = $result;
 
-            $combinedParams = $params + $this->psrRequest->getQueryParams();
+            $this->queryParams = $params + $this->psrRequest->getQueryParams();
 
-            return [$route, $combinedParams];
+            return [$route, $this->queryParams];
         }
 
         throw new NotFoundHttpException(Yii::t('yii', Message::PAGE_NOT_FOUND->getMessage()));

tests/TestCase.php

@@ -149,6 +149,7 @@ protected function statelessApplication(array $config = []): StatelessApplicatio
                             'enableStrictParsing' => false,
                             'enablePrettyUrl' => true,
                             'rules' => [
+                                'site/query/<test:\w+>' => 'site/query',
                                 'site/update/<id:\d+>' => 'site/update',
                             ],
                         ],

tests/http/StatelessApplicationTest.php

@@ -1238,6 +1238,39 @@ public function testReturnJsonResponseWithQueryParametersForSiteGetRoute(): void
         );
     }
 
+    public function testReturnJsonResponseWithQueryParamsForSiteQueryRoute(): void
+    {
+        $_GET = ['q' => '1'];
+        $_SERVER = [
+            'REQUEST_METHOD' => 'GET',
+            'REQUEST_URI' => 'site/query/foo?q=1',
+        ];
+
+        $request = FactoryHelper::createServerRequestCreator()->createFromGlobals();
+
+        $app = $this->statelessApplication();
+
+        $response = $app->handle($request);
+
+        self::assertSame(
+            200,
+            $response->getStatusCode(),
+            "Response 'status code' should be '200' for 'site/query/foo?q=1' route in 'StatelessApplication'.",
+        );
+        self::assertSame(
+            'application/json; charset=UTF-8',
+            $response->getHeaders()['content-type'][0] ?? '',
+            "Response 'content-type' should be 'application/json; charset=UTF-8' for 'site/query/foo?q=1' route in " .
+            "'StatelessApplication'.",
+        );
+        self::assertSame(
+            '{"test":"foo","q":"1","queryParams":{"test":"foo","q":"1"}}',
+            $response->getBody()->getContents(),
+            "Response 'body' should contain valid JSON with route and query parameters for 'site/query/foo?q=1' in " .
+            "'StatelessApplication'.",
+        );
+    }
+
     /**
      * @throws InvalidConfigException if the configuration is invalid or incomplete.
      */

tests/support/stub/SiteController.php

@@ -231,6 +231,20 @@ public function actionPost(): mixed
         return $this->request->post();
     }
 
+    /**
+     * @phpstan-return array<array-key, mixed>
+     */
+    public function actionQuery(string $test): array
+    {
+        $this->response->format = Response::FORMAT_JSON;
+
+        return [
+            'test' => $test,
+            'q' => $this->request->get('q'),
+            'queryParams' => $this->request->getQueryParams(),
+        ];
+    }
+
     /**
      * @throws InvalidRouteException
      */