#[derive(Clone, Hash, PartialEq, Eq, EncodeLabelSet, Debug)]
struct Escaping {
    client_version: String,
}

#[test]
fn label_value_is_escaped_in_text_exposition() {
    let mut registry = Registry::default();
    let family = Family::<Escaping, Counter>::default();
    registry.register("requests", "Requests", family.clone());
    family
        .get_or_create(&Escaping {
            client_version: r#"a"} evil{x="1"#.to_string(),
        })
        .inc();
    let mut buffer = String::new();
    encode(&mut buffer, &registry).unwrap();
    assert_eq!(
        r#"# HELP requests Requests.
# TYPE requests counter
requests_total{client_version="a\"} evil{x=\"1"} 1
# EOF
"#,
        buffer
    );
}