diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 37b06f9..913a436 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -12,7 +12,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        php: [7.4, 8.0, 8.1, 8.2, 8.3, 8.4]
+        php: [7.4, 8.0, 8.1, 8.2, 8.3, 8.4, 8.5]
 
     name: PHP ${{ matrix.php }}
 
@@ -32,4 +32,4 @@ jobs:
         run: composer update --no-interaction --no-progress
 
       - name: Execute tests
-        run: composer run tests
\ No newline at end of file
+        run: composer run tests
diff --git a/src/SchemaLoader.php b/src/SchemaLoader.php
index 1a2418d..231af82 100644
--- a/src/SchemaLoader.php
+++ b/src/SchemaLoader.php
@@ -242,7 +242,7 @@ protected function resolve(Uri $uri): ?Schema
      */
     protected function checkExistingObject(object $data): ?Schema
     {
-        if (!$this->dataCache->contains($data)) {
+        if (!$this->dataCache->offsetExists($data)) {
             return null;
         }
 
@@ -444,4 +444,4 @@ protected function createSchemaId($data): string
 
         return "schema:///{$data}.json";
     }
-}
\ No newline at end of file
+}