Fix: Do not attempt to return something from methods that do not retu…

…rn anything

tests/Assertions.php

@@ -4,12 +4,14 @@
 
 trait Assertions
 {
-    protected function assertRegExpCustom($expression, $string, $message = '')
+    protected function assertRegExpCustom($expression, $string, $message = ''): void
     {
         if (method_exists($this, 'assertMatchesRegularExpression')) {
-            return $this->assertMatchesRegularExpression($expression, $string, $message);
+            $this->assertMatchesRegularExpression($expression, $string, $message);
+
+            return;
         }
 
-        return $this->assertRegExp($expression, $string, $message);
+        $this->assertRegExp($expression, $string, $message);
     }
 }