rust-clippy/tests/ui/option_if_let_else.fixed
Jason Newcomb 8b3ca9a315
Fix option_if_let_else
* `break` and `continue` statments local to the would-be closure are allowed
* don't lint in const contexts
* don't lint when yield expressions are used
* don't lint when the captures made by the would-be closure conflict with the other branch
* don't lint when a field of a local is used when the type could be pontentially moved from
* in some cases, don't lint when scrutinee expression conflicts with the captures of the would-be closure
2021-08-16 16:12:00 -04:00

131 lines
2.9 KiB
Rust

// run-rustfix
#![warn(clippy::option_if_let_else)]
#![allow(clippy::redundant_closure)]
#![allow(clippy::ref_option_ref)]
fn bad1(string: Option<&str>) -> (bool, &str) {
string.map_or((false, "hello"), |x| (true, x))
}
fn else_if_option(string: Option<&str>) -> Option<(bool, &str)> {
if string.is_none() {
None
} else if let Some(x) = string {
Some((true, x))
} else {
Some((false, ""))
}
}
fn unop_bad(string: &Option<&str>, mut num: Option<i32>) {
let _ = string.map_or(0, |s| s.len());
let _ = num.as_ref().map_or(&0, |s| s);
let _ = num.as_mut().map_or(&mut 0, |s| {
*s += 1;
s
});
let _ = num.as_ref().map_or(&0, |s| s);
let _ = num.map_or(0, |mut s| {
s += 1;
s
});
let _ = num.as_mut().map_or(&mut 0, |s| {
*s += 1;
s
});
}
fn longer_body(arg: Option<u32>) -> u32 {
arg.map_or(13, |x| {
let y = x * x;
y * y
})
}
fn impure_else(arg: Option<i32>) {
let side_effect = || {
println!("return 1");
1
};
let _ = arg.map_or_else(|| side_effect(), |x| x);
}
fn test_map_or_else(arg: Option<u32>) {
let _ = arg.map_or_else(|| {
let mut y = 1;
y = (y + 2 / y) / 2;
y = (y + 2 / y) / 2;
y
}, |x| x * x * x * x);
}
fn negative_tests(arg: Option<u32>) -> u32 {
let _ = if let Some(13) = arg { "unlucky" } else { "lucky" };
for _ in 0..10 {
let _ = if let Some(x) = arg {
x
} else {
continue;
};
}
let _ = if let Some(x) = arg {
return x;
} else {
5
};
7
}
fn main() {
let optional = Some(5);
let _ = optional.map_or(5, |x| x + 2);
let _ = bad1(None);
let _ = else_if_option(None);
unop_bad(&None, None);
let _ = longer_body(None);
test_map_or_else(None);
let _ = negative_tests(None);
let _ = impure_else(None);
let _ = Some(0).map_or(0, |x| loop {
if x == 0 {
break x;
}
});
// #7576
const fn _f(x: Option<u32>) -> u32 {
// Don't lint, `map_or` isn't const
if let Some(x) = x { x } else { 10 }
}
// #5822
let s = String::new();
// Don't lint, `Some` branch consumes `s`, but else branch uses `s`
let _ = if let Some(x) = Some(0) {
let s = s;
s.len() + x
} else {
s.len()
};
let s = String::new();
// Lint, both branches immutably borrow `s`.
let _ = Some(0).map_or_else(|| s.len(), |x| s.len() + x);
let s = String::new();
// Lint, `Some` branch consumes `s`, but else branch doesn't use `s`.
let _ = Some(0).map_or(1, |x| {
let s = s;
s.len() + x
});
let s = Some(String::new());
// Don't lint, `Some` branch borrows `s`, but else branch consumes `s`
let _ = if let Some(x) = &s {
x.len()
} else {
let _s = s;
10
};
}