rust/tests/ui/trim_split_whitespace.rs

91 lines
2.5 KiB
Rust

#![warn(clippy::trim_split_whitespace)]
#![allow(clippy::let_unit_value)]
struct Custom;
impl Custom {
fn trim(self) -> Self {
self
}
fn split_whitespace(self) {}
}
struct DerefStr(&'static str);
impl std::ops::Deref for DerefStr {
type Target = str;
fn deref(&self) -> &Self::Target {
self.0
}
}
struct DerefStrAndCustom(&'static str);
impl std::ops::Deref for DerefStrAndCustom {
type Target = str;
fn deref(&self) -> &Self::Target {
self.0
}
}
impl DerefStrAndCustom {
fn trim(self) -> Self {
self
}
fn split_whitespace(self) {}
}
struct DerefStrAndCustomSplit(&'static str);
impl std::ops::Deref for DerefStrAndCustomSplit {
type Target = str;
fn deref(&self) -> &Self::Target {
self.0
}
}
impl DerefStrAndCustomSplit {
#[allow(dead_code)]
fn split_whitespace(self) {}
}
struct DerefStrAndCustomTrim(&'static str);
impl std::ops::Deref for DerefStrAndCustomTrim {
type Target = str;
fn deref(&self) -> &Self::Target {
self.0
}
}
impl DerefStrAndCustomTrim {
fn trim(self) -> Self {
self
}
}
fn main() {
// &str
let _ = " A B C ".trim().split_whitespace(); // should trigger lint
let _ = " A B C ".trim_start().split_whitespace(); // should trigger lint
let _ = " A B C ".trim_end().split_whitespace(); // should trigger lint
// String
let _ = (" A B C ").to_string().trim().split_whitespace(); // should trigger lint
let _ = (" A B C ").to_string().trim_start().split_whitespace(); // should trigger lint
let _ = (" A B C ").to_string().trim_end().split_whitespace(); // should trigger lint
// Custom
let _ = Custom.trim().split_whitespace(); // should not trigger lint
// Deref<Target=str>
let s = DerefStr(" A B C ");
let _ = s.trim().split_whitespace(); // should trigger lint
// Deref<Target=str> + custom impl
let s = DerefStrAndCustom(" A B C ");
let _ = s.trim().split_whitespace(); // should not trigger lint
// Deref<Target=str> + only custom split_ws() impl
let s = DerefStrAndCustomSplit(" A B C ");
let _ = s.trim().split_whitespace(); // should trigger lint
// Expl: trim() is called on str (deref) and returns &str.
// Thus split_ws() is called on str as well and the custom impl on S is unused
// Deref<Target=str> + only custom trim() impl
let s = DerefStrAndCustomTrim(" A B C ");
let _ = s.trim().split_whitespace(); // should not trigger lint
}