castep_cell_io/units/
length_units.rs

1use castep_cell_fmt::{Cell, CellValue, ToCell, ToCellValue};
2use castep_cell_fmt::parse::{FromCellValue, FromKeyValue};
3use castep_cell_fmt::{CResult, Error};
4use castep_cell_fmt::query::value_as_str;
5use serde::{Deserialize, Serialize};
6
7/// Specifies the units in which lengths will be reported.
8///
9/// Keyword type: String
10///
11/// Default: ang
12///
13/// Example:
14/// LENGTH_UNIT : bohr
15#[derive(
16    Debug, Clone, Copy, Hash, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord, Default,
17)]
18pub enum LengthUnit {
19    #[serde(alias = "BOHR", alias = "bohr")]
20    Bohr,
21    #[serde(alias = "a0", alias = "A0")]
22    BohrA0,
23    #[serde(alias = "M", alias = "m")]
24    Meter,
25    #[serde(alias = "CM", alias = "cm")]
26    Centimeter,
27    #[serde(alias = "NM", alias = "nm")]
28    Nanometer,
29    #[default]
30    #[serde(alias = "ANG", alias = "ang")]
31    Ang,
32}
33
34impl FromCellValue for LengthUnit {
35    fn from_cell_value(value: &CellValue<'_>) -> CResult<Self> {
36        match value_as_str(value)?.to_ascii_lowercase().as_str() {
37            "bohr" | "a0" => Ok(Self::Bohr),
38            "m" => Ok(Self::Meter),
39            "cm" => Ok(Self::Centimeter),
40            "nm" => Ok(Self::Nanometer),
41            "ang" => Ok(Self::Ang),
42            other => Err(Error::Message(format!("unknown LengthUnit: {other}"))),
43        }
44    }
45}
46
47impl FromKeyValue for LengthUnit {
48    const KEY_NAME: &'static str = "LENGTH_UNIT";
49
50    fn from_cell_value_kv(value: &CellValue<'_>) -> CResult<Self> {
51        Self::from_cell_value(value)
52    }
53}
54
55impl ToCellValue for LengthUnit {
56    fn to_cell_value(&self) -> CellValue<'_> {
57        CellValue::Str(match self {
58            LengthUnit::Bohr => "bohr",
59            LengthUnit::BohrA0 => "a0",
60            LengthUnit::Meter => "m",
61            LengthUnit::Centimeter => "cm",
62            LengthUnit::Nanometer => "nm",
63            LengthUnit::Ang => "ang",
64        })
65    }
66}
67
68impl ToCell for LengthUnit {
69    fn to_cell(&self) -> Cell<'_> {
70        Cell::KeyValue("LENGTH_UNIT", self.to_cell_value())
71    }
72}
73
74#[cfg(test)]
75mod tests {
76    use super::*;
77
78    #[test]
79    fn test_case_insensitive_parsing() {
80        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("bohr")).unwrap(), LengthUnit::Bohr);
81        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("BOHR")).unwrap(), LengthUnit::Bohr);
82        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("ang")).unwrap(), LengthUnit::Ang);
83        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("ANG")).unwrap(), LengthUnit::Ang);
84    }
85
86    #[test]
87    fn test_bohr_alias() {
88        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("a0")).unwrap(), LengthUnit::Bohr);
89        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("A0")).unwrap(), LengthUnit::Bohr);
90    }
91
92    #[test]
93    fn test_all_variants() {
94        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("m")).unwrap(), LengthUnit::Meter);
95        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("cm")).unwrap(), LengthUnit::Centimeter);
96        assert_eq!(LengthUnit::from_cell_value(&CellValue::Str("nm")).unwrap(), LengthUnit::Nanometer);
97    }
98
99    #[test]
100    fn test_invalid_variant() {
101        assert!(LengthUnit::from_cell_value(&CellValue::Str("invalid")).is_err());
102    }
103
104    #[test]
105    fn test_key_name() {
106        assert_eq!(LengthUnit::KEY_NAME, "LENGTH_UNIT");
107    }
108
109    #[test]
110    fn test_default() {
111        assert_eq!(LengthUnit::default(), LengthUnit::Ang);
112    }
113
114    #[test]
115    fn test_to_cell_value() {
116        assert_eq!(LengthUnit::Bohr.to_cell_value(), CellValue::Str("bohr"));
117        assert_eq!(LengthUnit::Meter.to_cell_value(), CellValue::Str("m"));
118        assert_eq!(LengthUnit::Centimeter.to_cell_value(), CellValue::Str("cm"));
119        assert_eq!(LengthUnit::Nanometer.to_cell_value(), CellValue::Str("nm"));
120        assert_eq!(LengthUnit::Ang.to_cell_value(), CellValue::Str("ang"));
121    }
122
123    #[test]
124    fn test_to_cell() {
125        let cell = LengthUnit::Ang.to_cell();
126        match cell {
127            Cell::KeyValue(key, _) => assert_eq!(key, "LENGTH_UNIT"),
128            _ => panic!("Expected KeyValue cell"),
129        }
130    }
131}
castep_cell_io/units/length_units.rs

castep_cell_io/units/
length_units.rs
