@Test
void stringVariable() {

    assertThat(Literal.variable("\n")).isEqualTo("\"\\n\"");
    assertThat(Literal.variable("\r")).isEqualTo("\"\\r\"");
    assertThat(Literal.variable("\\")).isEqualTo("\"\\\\\"");
    assertThat(Literal.variable("\"")).isEqualTo("\"\\\"\"");
}