1 use std::fmt; 2 3 use crate::{capitalize, transform}; 4 5 /// This trait defines a train case conversion. 6 /// 7 /// In Train-Case, word boundaries are indicated by hyphens and words start 8 /// with Capital Letters. 9 /// 10 /// ## Example: 11 /// 12 /// ```rust 13 /// use heck::ToTrainCase; 14 /// 15 /// let sentence = "We are going to inherit the earth."; 16 /// assert_eq!(sentence.to_train_case(), "We-Are-Going-To-Inherit-The-Earth"); 17 /// ``` 18 pub trait ToTrainCase: ToOwned { 19 /// Convert this type to Train-Case. to_train_case(&self) -> Self::Owned20 fn to_train_case(&self) -> Self::Owned; 21 } 22 23 impl ToTrainCase for str { to_train_case(&self) -> Self::Owned24 fn to_train_case(&self) -> Self::Owned { 25 AsTrainCase(self).to_string() 26 } 27 } 28 29 /// This wrapper performs a train case conversion in [`fmt::Display`]. 30 /// 31 /// ## Example: 32 /// 33 /// ``` 34 /// use heck::AsTrainCase; 35 /// 36 /// let sentence = "We are going to inherit the earth."; 37 /// assert_eq!(format!("{}", AsTrainCase(sentence)), "We-Are-Going-To-Inherit-The-Earth"); 38 /// ``` 39 pub struct AsTrainCase<T: AsRef<str>>(pub T); 40 41 impl<T: AsRef<str>> fmt::Display for AsTrainCase<T> { fmt(&self, f: &mut fmt::Formatter) -> fmt::Result42 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { 43 transform(self.0.as_ref(), capitalize, |f| write!(f, "-"), f) 44 } 45 } 46 47 #[cfg(test)] 48 mod tests { 49 use super::ToTrainCase; 50 51 macro_rules! t { 52 ($t:ident : $s1:expr => $s2:expr) => { 53 #[test] 54 fn $t() { 55 assert_eq!($s1.to_train_case(), $s2) 56 } 57 }; 58 } 59 60 t!(test1: "CamelCase" => "Camel-Case"); 61 t!(test2: "This is Human case." => "This-Is-Human-Case"); 62 t!(test3: "MixedUP CamelCase, with some Spaces" => "Mixed-Up-Camel-Case-With-Some-Spaces"); 63 t!(test4: "mixed_up_ snake_case with some _spaces" => "Mixed-Up-Snake-Case-With-Some-Spaces"); 64 t!(test5: "kebab-case" => "Kebab-Case"); 65 t!(test6: "SHOUTY_SNAKE_CASE" => "Shouty-Snake-Case"); 66 t!(test7: "snake_case" => "Snake-Case"); 67 t!(test8: "this-contains_ ALLKinds OfWord_Boundaries" => "This-Contains-All-Kinds-Of-Word-Boundaries"); 68 #[cfg(feature = "unicode")] 69 t!(test9: "XΣXΣ baffle" => "Xσxς-Baffle"); 70 t!(test10: "XMLHttpRequest" => "Xml-Http-Request"); 71 t!(test11: "FIELD_NAME11" => "Field-Name11"); 72 t!(test12: "99BOTTLES" => "99bottles"); 73 t!(test13: "FieldNamE11" => "Field-Nam-E11"); 74 t!(test14: "abc123def456" => "Abc123def456"); 75 t!(test16: "abc123DEF456" => "Abc123-Def456"); 76 t!(test17: "abc123Def456" => "Abc123-Def456"); 77 t!(test18: "abc123DEf456" => "Abc123-D-Ef456"); 78 t!(test19: "ABC123def456" => "Abc123def456"); 79 t!(test20: "ABC123DEF456" => "Abc123def456"); 80 t!(test21: "ABC123Def456" => "Abc123-Def456"); 81 t!(test22: "ABC123DEf456" => "Abc123d-Ef456"); 82 t!(test23: "ABC123dEEf456FOO" => "Abc123d-E-Ef456-Foo"); 83 t!(test24: "abcDEF" => "Abc-Def"); 84 t!(test25: "ABcDE" => "A-Bc-De"); 85 } 86