xref: /third_party/rust/crates/heck/src/kebab.rs (revision 6fccd0a4) 
1use std::fmt;
2
3use crate::{lowercase, transform};
4
5/// This trait defines a kebab case conversion.
6///
7/// In kebab-case, word boundaries are indicated by hyphens.
8///
9/// ## Example:
10///
11/// ```rust
12/// use heck::ToKebabCase;
13///
14/// let sentence = "We are going to inherit the earth.";
15/// assert_eq!(sentence.to_kebab_case(), "we-are-going-to-inherit-the-earth");
16/// ```
17pub trait ToKebabCase: ToOwned {
18    /// Convert this type to kebab case.
19    fn to_kebab_case(&self) -> Self::Owned;
20}
21
22impl ToKebabCase for str {
23    fn to_kebab_case(&self) -> Self::Owned {
24        AsKebabCase(self).to_string()
25    }
26}
27
28/// This wrapper performs a kebab case conversion in [`fmt::Display`].
29///
30/// ## Example:
31///
32/// ```
33/// use heck::AsKebabCase;
34///
35/// let sentence = "We are going to inherit the earth.";
36/// assert_eq!(format!("{}", AsKebabCase(sentence)), "we-are-going-to-inherit-the-earth");
37/// ```
38pub struct AsKebabCase<T: AsRef<str>>(pub T);
39
40impl<T: AsRef<str>> fmt::Display for AsKebabCase<T> {
41    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
42        transform(self.0.as_ref(), lowercase, |f| write!(f, "-"), f)
43    }
44}
45
46#[cfg(test)]
47mod tests {
48    use super::ToKebabCase;
49
50    macro_rules! t {
51        ($t:ident : $s1:expr => $s2:expr) => {
52            #[test]
53            fn $t() {
54                assert_eq!($s1.to_kebab_case(), $s2)
55            }
56        };
57    }
58
59    t!(test1: "CamelCase" => "camel-case");
60    t!(test2: "This is Human case." => "this-is-human-case");
61    t!(test3: "MixedUP CamelCase, with some Spaces" => "mixed-up-camel-case-with-some-spaces");
62    t!(test4: "mixed_up_ snake_case with some _spaces" => "mixed-up-snake-case-with-some-spaces");
63    t!(test5: "kebab-case" => "kebab-case");
64    t!(test6: "SHOUTY_SNAKE_CASE" => "shouty-snake-case");
65    t!(test7: "snake_case" => "snake-case");
66    t!(test8: "this-contains_ ALLKinds OfWord_Boundaries" => "this-contains-all-kinds-of-word-boundaries");
67    #[cfg(feature = "unicode")]
68    t!(test9: "XΣXΣ baffle" => "xσxς-baffle");
69    t!(test10: "XMLHttpRequest" => "xml-http-request");
70}
71