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pub fn remove_to<'s, P>(s: &'s str, pattern: P) -> &'s str
where
P: Fn(char) -> bool,
{
match s.rfind(pattern) {
Some(pos) => &s[(pos + 1)..],
None => s,
}
}
pub fn remove_suffix<'s>(s: &'s str, suffix: &str) -> &'s str {
if !s.ends_with(suffix) {
s
} else {
&s[..(s.len() - suffix.len())]
}
}
pub fn capitalize(s: &str) -> String {
if s.is_empty() {
return String::new();
}
let mut char_indices = s.char_indices();
char_indices.next().unwrap();
match char_indices.next() {
None => s.to_uppercase(),
Some((i, _)) => s[..i].to_uppercase() + &s[i..],
}
}
#[cfg(test)]
mod test {
use super::capitalize;
use super::remove_suffix;
use super::remove_to;
#[test]
fn test_remove_to() {
assert_eq!("aaa", remove_to("aaa", |c| c == '.'));
assert_eq!("bbb", remove_to("aaa.bbb", |c| c == '.'));
assert_eq!("ccc", remove_to("aaa.bbb.ccc", |c| c == '.'));
}
#[test]
fn test_remove_suffix() {
assert_eq!("bbb", remove_suffix("bbbaaa", "aaa"));
assert_eq!("aaa", remove_suffix("aaa", "bbb"));
}
#[test]
fn test_capitalize() {
assert_eq!("", capitalize(""));
assert_eq!("F", capitalize("f"));
assert_eq!("Foo", capitalize("foo"));
}
}
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