diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 8805ecdd..eb6a0ae6 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -133,7 +133,7 @@ jobs:
         moodle-plugin-ci phplint
         moodle-plugin-ci phpcpd
         moodle-plugin-ci phpmd
-        moodle-plugin-ci phpcs
+        moodle-plugin-ci phpcs --max-warnings 0
         moodle-plugin-ci phpcbf
         moodle-plugin-ci validate
         moodle-plugin-ci savepoints
@@ -250,7 +250,7 @@ jobs:
         php build/moodle-plugin-ci.phar phplint
         php build/moodle-plugin-ci.phar phpcpd
         php build/moodle-plugin-ci.phar phpmd
-        php build/moodle-plugin-ci.phar phpcs
+        php build/moodle-plugin-ci.phar phpcs --max-warnings 0
         php build/moodle-plugin-ci.phar phpcbf
         php build/moodle-plugin-ci.phar validate
         php build/moodle-plugin-ci.phar savepoints
diff --git a/tests/Fixture/moodle-local_ci/tests/lib_test.php b/tests/Fixture/moodle-local_ci/tests/lib_test.php
index e0672b45..5435561d 100644
--- a/tests/Fixture/moodle-local_ci/tests/lib_test.php
+++ b/tests/Fixture/moodle-local_ci/tests/lib_test.php
@@ -37,13 +37,13 @@
  * @copyright Copyright (c) 2015 Blackboard Inc. (http://www.blackboard.com)
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class lib_test extends \basic_testcase {
+final class lib_test extends \basic_testcase {
     /**
      * Test addition.
      *
      * @covers ::local_ci_add
      */
-    public function test_local_ci_add() {
+    public function test_local_ci_add(): void {
         $this->assertEquals(4, local_ci_add(2, 2));
         $this->assertEquals(2, local_ci_add(4, -2));
         $this->assertEquals(0, local_ci_add(-4, 4));
@@ -54,7 +54,7 @@ public function test_local_ci_add() {
      *
      * @covers ::local_ci_subtract
      */
-    public function test_local_ci_subtract() {
+    public function test_local_ci_subtract(): void {
         $this->assertEquals(0, local_ci_subtract(2, 2));
         $this->assertEquals(6, local_ci_subtract(4, -2));
         $this->assertEquals(-8, local_ci_subtract(-4, 4));
@@ -65,7 +65,7 @@ public function test_local_ci_subtract() {
      *
      * @covers \local_ci\math::add
      */
-    public function test_local_ci_math() {
+    public function test_local_ci_math(): void {
         $math = new \local_ci_math();
         $this->assertEquals(4, $math->add(2, 2));
         $this->assertEquals(2, $math->add(4, -2));
@@ -77,7 +77,7 @@ public function test_local_ci_math() {
      *
      * @covers \local_ci\math::add
      */
-    public function test_local_ci_math_class() {
+    public function test_local_ci_math_class(): void {
         $math = new math();
         $this->assertEquals(4, $math->add(2, 2));
         $this->assertEquals(2, $math->add(4, -2));