diff --git a/tests/Unit/BillingPortal/DependencyTest.php b/tests/Unit/BillingPortal/DependencyTest.php
index b8612c442b32..23453f5ee271 100644
--- a/tests/Unit/BillingPortal/DependencyTest.php
+++ b/tests/Unit/BillingPortal/DependencyTest.php
@@ -100,7 +100,7 @@ class DependencyTest extends TestCase
     private function checkDependencies(array $steps): array
     {
         $dependencies = Purchase::$dependencies;
-        $stepOrder = array_flip($steps);
+        $step_order = array_flip($steps);
         $errors = [];
     
         foreach ($steps as $step) {
@@ -111,7 +111,7 @@ class DependencyTest extends TestCase
             }
     
             foreach ($dependent as $dependency) {
-                if (in_array($dependency, $steps) && $stepOrder[$dependency] > $stepOrder[$step]) {
+                if (in_array($dependency, $steps) && $step_order[$dependency] > $step_order[$step]) {
                     $errors[] = "Dependency error: $step depends on $dependency";
                 }
             }