music21_rs/
rest.rs

1use crate::duration::Duration;
2
3/// A silent musical event with a duration.
4#[derive(Clone, Debug, PartialEq)]
5#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
6#[must_use]
7pub struct Rest {
8    duration: Duration,
9}
10
11impl Rest {
12    /// Creates a rest with the supplied duration.
13    pub fn new(duration: Duration) -> Self {
14        Self { duration }
15    }
16
17    /// Creates a rest from a quarter-length value.
18    pub fn from_quarter_length(quarter_length: crate::FloatType) -> crate::Result<Self> {
19        Ok(Self::new(Duration::new(quarter_length)?))
20    }
21
22    /// Returns the rest duration.
23    pub fn duration(&self) -> &Duration {
24        &self.duration
25    }
26
27    /// Updates the rest duration.
28    pub fn set_duration(&mut self, duration: Duration) {
29        self.duration = duration;
30    }
31
32    /// Returns the duration in quarter lengths.
33    pub fn quarter_length(&self) -> crate::FloatType {
34        self.duration.quarter_length()
35    }
36
37    /// The most complete name of the rest, its length included: music21's
38    /// `fullName`, `Dotted Quarter Rest`.
39    pub fn full_name(&self) -> String {
40        format!("{} Rest", self.duration.full_name())
41    }
42}
43
44impl Default for Rest {
45    fn default() -> Self {
46        Self::new(Duration::default())
47    }
48}
49
50impl From<Duration> for Rest {
51    fn from(value: Duration) -> Self {
52        Self::new(value)
53    }
54}
55
56#[cfg(test)]
57mod tests {
58    use super::*;
59
60    #[test]
61    fn rest_has_duration() {
62        let rest = Rest::from_quarter_length(2.0).unwrap();
63        assert_eq!(rest.quarter_length(), 2.0);
64    }
65
66    #[test]
67    fn a_rest_is_named_by_its_length() {
68        assert_eq!(
69            Rest::from_quarter_length(1.5).unwrap().full_name(),
70            "Dotted Quarter Rest"
71        );
72        assert_eq!(Rest::new(Duration::whole()).full_name(), "Whole Rest");
73    }
74
75    #[test]
76    fn rest_supports_default_from_and_updates() {
77        let mut rest = Rest::default();
78        assert_eq!(rest.quarter_length(), 1.0);
79
80        rest.set_duration(Duration::whole());
81        assert_eq!(rest.duration(), &Duration::whole());
82
83        let half_rest = Rest::from(Duration::half());
84        assert_eq!(half_rest.quarter_length(), 2.0);
85        assert!(Rest::from_quarter_length(crate::FloatType::NAN).is_err());
86    }
87}
music21_rs/rest.rs

music21_rs/
rest.rs
