Issue #3129680 by mpp, dww, RedEight, Feng-Shui: Declare compatibility with Drupal 9

condition_query.info.yml

@@ -2,3 +2,4 @@ name: Condition Query
 type: module
 description: "Adds condition plugin by query parameter"
 core: 8.x
+core_version_requirement: ^8 || ^9

tests/src/Kernel/RequestParamConditionTest.php

@@ -33,12 +33,12 @@ class RequestParamConditionTest extends KernelTestBase {
    *
    * @var array
    */
-  public static $modules = ['system', 'user', 'condition_query'];
+  protected static $modules = ['system', 'user', 'condition_query'];
 
   /**
    * {@inheritdoc}
    */
-  protected function setUp() {
+  protected function setUp() : void {
     parent::setUp();
 
     $this->installSchema('system', ['sequences']);
@@ -53,7 +53,7 @@ class RequestParamConditionTest extends KernelTestBase {
   /**
    * Tests the request param condition.
    */
-  public function testConditions() {
+  public function testConditions() : void {
 
     /* @var \Drupal\condition_query\Plugin\Condition\RequestParam $condition */
     $condition = $this->pluginManager->createInstance('request_param');