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

#![cfg_attr(test, deny(missing_docs))]
#![cfg_attr(test, deny(warnings))]

//! # Case
//!
//! Case provices a way of specifying strings that are case-insensitive.
//!
//! ## Example
//!
//! ```rust
//! use unicase::UniCase;
//!
//! let a = UniCase("foobar");
//! let b = UniCase("FoObAr");
//!
//! assert_eq!(a, b);
//! ```

use std::ascii::AsciiExt;
#[cfg(iter_cmp)]
use std::cmp::Ordering;
use std::fmt;
use std::hash::{Hash, Hasher};
use std::ops::{Deref, DerefMut};
use std::str::FromStr;

/// Case Insensitive wrapper of strings.
#[derive(Clone, Debug)]
pub struct UniCase<S>(pub S);

impl<S> Deref for UniCase<S> {
    type Target = S;
    #[inline]
    fn deref<'a>(&'a self) -> &'a S {
        &self.0
    }
}

impl<S> DerefMut for UniCase<S> {
    #[inline]
    fn deref_mut<'a>(&'a mut self) -> &'a mut S {
        &mut self.0
    }
}

#[cfg(iter_cmp)]
impl<T: AsRef<str>> PartialOrd for UniCase<T> {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

#[cfg(iter_cmp)]
impl<T: AsRef<str>> Ord for UniCase<T> {
    fn cmp(&self, other: &Self) -> Ordering {
        let self_chars = self.as_ref().chars().map(|c| c.to_ascii_lowercase());
        let other_chars = other.as_ref().chars().map(|c| c.to_ascii_lowercase());
        self_chars.cmp(other_chars)
    }
}

impl<S: AsRef<str>> AsRef<str> for UniCase<S> {
    #[inline]
    fn as_ref(&self) -> &str {
        self.0.as_ref()
    }

}

impl<S: fmt::Display> fmt::Display for UniCase<S> {
    #[inline]
    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
        fmt::Display::fmt(&self.0, fmt)
    }
}

impl<S: AsRef<str>> PartialEq for UniCase<S> {
    #[inline]
    fn eq(&self, other: &UniCase<S>) -> bool {
        self.as_ref().eq_ignore_ascii_case(other.as_ref())
    }
}


impl<S: AsRef<str>> PartialEq<S> for UniCase<S> {
    #[inline]
    fn eq(&self, other: &S) -> bool {
        self.as_ref().eq_ignore_ascii_case(other.as_ref())
    }
}

impl<S: AsRef<str>> Eq for UniCase<S> {}

impl<S: FromStr> FromStr for UniCase<S> {
    type Err = <S as FromStr>::Err;
    fn from_str(s: &str) -> Result<UniCase<S>, <S as FromStr>::Err> {
        s.parse().map(UniCase)
    }
}

impl<S: AsRef<str>> Hash for UniCase<S> {
    #[inline]
    fn hash<H: Hasher>(&self, hasher: &mut H) {
        for byte in self.as_ref().bytes().map(|b| b.to_ascii_lowercase()) {
            hasher.write(&[byte]);
        }
    }
}

#[cfg(test)]
mod test {
    use super::UniCase;
    use std::hash::{Hash, Hasher, SipHasher};

    fn hash<T: Hash>(t: &T) -> u64 {
        let mut s = SipHasher::new();
        t.hash(&mut s);
        s.finish()
    }

    #[test]
    fn test_case_insensitive() {
        let a = UniCase("foobar");
        let b = UniCase("FOOBAR");

        assert_eq!(a, b);
        assert_eq!(hash(&a), hash(&b));
    }

    #[cfg(iter_cmp)]
    #[test]
    fn test_case_cmp() {
        assert!(UniCase("foobar") == UniCase("FOOBAR"));
        assert!(UniCase("a") < UniCase("B"));

        assert!(UniCase("A") < UniCase("b"));
        assert!(UniCase("aa") > UniCase("a"));

        assert!(UniCase("a") < UniCase("aa"));
        assert!(UniCase("a") < UniCase("AA"));
    }
}