rust/clippy_lints/src/utils/camel_case.rs
Andre Bogus cc622608db new lints around #[must_use] fns
`must_use_unit` lints unit-returning functions with a `#[must_use]`
attribute, suggesting to remove it.

`double_must_use` lints functions with a plain `#[must_use]`
attribute, but which return a type which is already `#[must_use]`,
so the attribute has no benefit.

`must_use_candidate` is a pedantic lint that lints functions and
methods that return some non-unit type that is not already
`#[must_use]` and suggests to add the annotation.
2019-10-14 12:09:04 +02:00

116 lines
2.4 KiB
Rust

/// Returns the index of the character after the first camel-case component of `s`.
#[must_use]
pub fn until(s: &str) -> usize {
let mut iter = s.char_indices();
if let Some((_, first)) = iter.next() {
if !first.is_uppercase() {
return 0;
}
} else {
return 0;
}
let mut up = true;
let mut last_i = 0;
for (i, c) in iter {
if up {
if c.is_lowercase() {
up = false;
} else {
return last_i;
}
} else if c.is_uppercase() {
up = true;
last_i = i;
} else if !c.is_lowercase() {
return i;
}
}
if up {
last_i
} else {
s.len()
}
}
/// Returns index of the last camel-case component of `s`.
#[must_use]
pub fn from(s: &str) -> usize {
let mut iter = s.char_indices().rev();
if let Some((_, first)) = iter.next() {
if !first.is_lowercase() {
return s.len();
}
} else {
return s.len();
}
let mut down = true;
let mut last_i = s.len();
for (i, c) in iter {
if down {
if c.is_uppercase() {
down = false;
last_i = i;
} else if !c.is_lowercase() {
return last_i;
}
} else if c.is_lowercase() {
down = true;
} else {
return last_i;
}
}
last_i
}
#[cfg(test)]
mod test {
use super::{from, until};
#[test]
fn from_full() {
assert_eq!(from("AbcDef"), 0);
assert_eq!(from("Abc"), 0);
}
#[test]
fn from_partial() {
assert_eq!(from("abcDef"), 3);
assert_eq!(from("aDbc"), 1);
}
#[test]
fn from_not() {
assert_eq!(from("AbcDef_"), 7);
assert_eq!(from("AbcDD"), 5);
}
#[test]
fn from_caps() {
assert_eq!(from("ABCD"), 4);
}
#[test]
fn until_full() {
assert_eq!(until("AbcDef"), 6);
assert_eq!(until("Abc"), 3);
}
#[test]
fn until_not() {
assert_eq!(until("abcDef"), 0);
assert_eq!(until("aDbc"), 0);
}
#[test]
fn until_partial() {
assert_eq!(until("AbcDef_"), 6);
assert_eq!(until("CallTypeC"), 8);
assert_eq!(until("AbcDD"), 3);
}
#[test]
fn until_caps() {
assert_eq!(until("ABCD"), 0);
}
}