===description===
literalConcatWithStringCreatesString
===file===
<?php
                    /**
                     * @param  literal-string $s2
                     * @return literal-string
                     */
                    function foo(string $s1, string $s2): string {
                        return $s1 . $s2;
                    }
===expect===
LessSpecificReturnStatement
===ignore===
TODO
