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
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160

use convert_case::{Casing, Case};

#[cfg(test)]
use strum_macros::EnumIter;

#[cfg_attr(test, derive(EnumIter))]
#[derive(PartialEq, Eq)]
pub enum CaseKind {
    SpaceDelim,
    UnderscoreDelim,
    NoDelim,
    HyphenDelim,
    CapitalDelim,
    Random,
}

impl CaseKind {
    pub fn from_case(c: Case) -> Self {
        use Case::*;
        use CaseKind::*;
        match c {
            Upper | Lower | Title | Toggle | Alternating => SpaceDelim,
            Snake | UpperSnake | ScreamingSnake => UnderscoreDelim,
            Kebab | Cobol | Train => HyphenDelim,
            Flat | UpperFlat => NoDelim,
            Camel | UpperCamel | Pascal => CapitalDelim,
            Case::Random | PseudoRandom => CaseKind::Random,
        }
    }

    pub const fn all_kinds() -> [CaseKind; 6] {
        use CaseKind::*;
        [
            SpaceDelim,
            CapitalDelim,
            UnderscoreDelim,
            HyphenDelim,
            NoDelim,
            Random,
        ]
    }

    pub fn name(&self) -> &'static str {
        use CaseKind::*;
        match self {
            SpaceDelim => "Space Delimited",
            UnderscoreDelim => "Underscore Delimited",
            NoDelim => "No Delimiter",
            HyphenDelim => "Hyphen Delimited",
            CapitalDelim => "Capitalization Boundaries",
            Random => "Random Capitalization",
        }
    }
}

pub trait CaseClassification {
    fn name_in_case(self) -> String;
    fn is_alias(&self) -> Option<Case>;
    fn kind(&self) -> CaseKind;
    fn short_name(&self) -> Option<&'static str>;
    fn from_str(_: &str) -> Result<Case, ()>;
    fn list();
}

impl CaseClassification for Case {
    // Returns the name of the case in it's own case
    fn name_in_case(self) -> String {
        let case_str = format!("{:?}Case", self);
        case_str.to_case(self)
    }

    // Returns None if case is not an alias for another case,
    // other Some containing the other case
    fn is_alias(&self) -> Option<Case> {
        use Case::*;
        match self {
            UpperCamel => Some(Pascal),
            ScreamingSnake => Some(UpperSnake),
            _ => None
        }
    }

    // Maps a case to its cooresponding CaseKind
    fn kind(&self) -> CaseKind {
        use Case::*;
        use CaseKind::*;
        match self {
            Upper | Lower | Title | Toggle | Alternating => SpaceDelim,
            Snake | UpperSnake | ScreamingSnake => UnderscoreDelim,
            Kebab | Cobol | Train => HyphenDelim,
            Flat | UpperFlat => NoDelim,
            Camel | UpperCamel | Pascal => CapitalDelim,
            Case::Random | PseudoRandom => CaseKind::Random,
        }
    }

    // Returns the short name variant of a case name if it exists
    fn short_name(&self) -> Option<&'static str> {
        use Case::*;
        match self {
            PseudoRandom => Some("pseudo"),
            ScreamingSnake => Some("screaming"),
            Alternating => Some("alternate"),
            _ => None,
        }
    }

    // Tries to convert a string slice to a Case
    fn from_str(s: &str) -> Result<Case, ()> {
        let case_str = s.to_case(Case::Flat);
        for case in Case::all_cases() {
            if case_str == format!("{:?}", case).to_case(Case::Flat) {
                return Ok(case);
            }
            if let Some(short) = case.short_name() {
                if case_str == short {
                    return Ok(case);
                }
            }
        }
        Err(())
    }

    // Prints to the screen a list of cases
    fn list() {
        for kind in &CaseKind::all_kinds() {
            println!("{}:", kind.name());
            for case in Case::all_cases()
                .iter()
                .filter(|&x| x.kind() == *kind)
            {
                println!("  {:<16} {}", format!("{:?}", case), case.name_in_case());
                if let Some(short) = case.short_name() {
                    println!("   (or {})", short);
                }
            }
            println!();
        }
    }
}

#[cfg(test)]
mod test {

    use super::*;
    use strum::IntoEnumIterator;

    #[test]
    fn all_kinds_in_iter() {
        for kind in CaseKind::iter() {
            assert!(CaseKind::all_kinds().contains(&kind));
        }
    }

    #[test]
    fn short_name_to_case() {
        assert_eq!(Case::from_str("pseudo").unwrap(), Case::PseudoRandom);
    }

}