1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56

use std::fmt;

/// A VCF header record value.
#[derive(Clone, Debug, Eq, PartialEq)]
pub enum Value {
    /// A string.
    String(String),
    /// A structure.
    Struct(Vec<(String, String)>),
}

impl fmt::Display for Value {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::String(value) => f.write_str(value),
            Self::Struct(fields) => {
                for (i, (key, value)) in fields.iter().enumerate() {
                    if i > 0 {
                        f.write_str(",")?;
                    }

                    write!(f, "{}={}", key, value)?;
                }

                Ok(())
            }
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_fmt() {
        assert_eq!(
            Value::String(String::from("VCFv4.3")).to_string(),
            "VCFv4.3"
        );

        assert_eq!(
            Value::Struct(vec![(String::from("ID"), String::from("sq0"))]).to_string(),
            "ID=sq0"
        );

        assert_eq!(
            Value::Struct(vec![
                (String::from("ID"), String::from("sq0")),
                (String::from("length"), String::from("13"))
            ])
            .to_string(),
            "ID=sq0,length=13"
        );
    }
}