diff --git a/tests/Rules/NarrowPublicClassMethodParamTypeRule/Fixture/ExplicitlyNullableParams.php b/tests/Rules/NarrowPublicClassMethodParamTypeRule/Fixture/ExplicitlyNullableParams.php
new file mode 100644
index 00000000..68e1d5e4
--- /dev/null
+++ b/tests/Rules/NarrowPublicClassMethodParamTypeRule/Fixture/ExplicitlyNullableParams.php
@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\TypePerfect\Tests\Rules\NarrowPublicClassMethodParamTypeRule\Fixture;
+
+final class ExplicitlyNullableParams
+{
+    public function test(
+        ?bool $bool = true,
+    ): bool
+    {
+        return $bool;
+    }
+
+    static public function run(): void
+    {
+        $skipDateTimeMix = new ExplicitlyNullableParams();
+        $skipDateTimeMix->test(false);
+    }
+}
diff --git a/tests/Rules/NarrowPublicClassMethodParamTypeRule/NarrowPublicClassMethodParamTypeRuleTest.php b/tests/Rules/NarrowPublicClassMethodParamTypeRule/NarrowPublicClassMethodParamTypeRuleTest.php
index a62308c4..ff2044be 100644
--- a/tests/Rules/NarrowPublicClassMethodParamTypeRule/NarrowPublicClassMethodParamTypeRuleTest.php
+++ b/tests/Rules/NarrowPublicClassMethodParamTypeRule/NarrowPublicClassMethodParamTypeRuleTest.php
@@ -155,7 +155,11 @@ public static function provideData(): Iterator
         yield [[__DIR__ . '/Fixture/SkipEnum.php'], []];
 
         $argErrorMessage = sprintf(NarrowPublicClassMethodParamTypeRule::ERROR_MESSAGE, 'int');
+
         yield [[__DIR__ . '/Fixture/HandleDefaultValue.php'], [[$argErrorMessage, 15]]];
+
+        $argErrorMessage = sprintf(NarrowPublicClassMethodParamTypeRule::ERROR_MESSAGE, 'bool');
+        yield [[__DIR__ . '/Fixture/ExplicitlyNullableParams.php'], [[$argErrorMessage, 9]]];
     }
 
     /**