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//@run-rustfix
#![warn(clippy::option_if_let_else)]
#![allow(
unused_tuple_struct_fields,
clippy::redundant_closure,
clippy::ref_option_ref,
clippy::equatable_if_let,
clippy::let_unit_value
)]
fn bad1(string: Option<&str>) -> (bool, &str) {
if let Some(x) = string {
(true, x)
} else {
(false, "hello")
}
}
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 _ = if let Some(s) = *string { s.len() } else { 0 };
let _ = if let Some(s) = &num { s } else { &0 };
let _ = if let Some(s) = &mut num {
*s += 1;
s
} else {
&0
};
let _ = if let Some(ref s) = num { s } else { &0 };
let _ = if let Some(mut s) = num {
s += 1;
s
} else {
0
};
let _ = if let Some(ref mut s) = num {
*s += 1;
s
} else {
&0
};
}
fn longer_body(arg: Option<u32>) -> u32 {
if let Some(x) = arg {
let y = x * x;
y * y
} else {
13
}
}
fn impure_else(arg: Option<i32>) {
let side_effect = || {
println!("return 1");
1
};
let _ = if let Some(x) = arg {
x
} else {
// map_or_else must be suggested
side_effect()
};
}
fn test_map_or_else(arg: Option<u32>) {
let _ = if let Some(x) = arg {
x * x * x * x
} else {
let mut y = 1;
y = (y + 2 / y) / 2;
y = (y + 2 / y) / 2;
y
};
}
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
}
// #7973
fn pattern_to_vec(pattern: &str) -> Vec<String> {
pattern
.trim_matches('/')
.split('/')
.flat_map(|s| {
if let Some(idx) = s.find('.') {
vec![s[..idx].to_string(), s[idx..].to_string()]
} else {
vec![s.to_string()]
}
})
.collect::<Vec<_>>()
}
enum DummyEnum {
One(u8),
Two,
}
// should not warn since there is a complex subpat
// see #7991
fn complex_subpat() -> DummyEnum {
let x = Some(DummyEnum::One(1));
let _ = if let Some(_one @ DummyEnum::One(..)) = x { 1 } else { 2 };
DummyEnum::Two
}
fn main() {
let optional = Some(5);
let _ = if let Some(x) = optional { x + 2 } else { 5 };
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 _ = if let Some(x) = Some(0) {
loop {
if x == 0 {
break x;
}
}
} else {
0
};
// #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 _ = if let Some(x) = Some(0) { s.len() + x } else { s.len() };
let s = String::new();
// Lint, `Some` branch consumes `s`, but else branch doesn't use `s`.
let _ = if let Some(x) = Some(0) {
let s = s;
s.len() + x
} else {
1
};
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
};
let mut s = Some(String::new());
// Don't lint, `Some` branch mutably borrows `s`, but else branch also borrows `s`
let _ = if let Some(x) = &mut s {
x.push_str("test");
x.len()
} else {
let _s = &s;
10
};
async fn _f1(x: u32) -> u32 {
x
}
async fn _f2() {
// Don't lint. `await` can't be moved into a closure.
let _ = if let Some(x) = Some(0) { _f1(x).await } else { 0 };
}
let _ = pattern_to_vec("hello world");
let _ = complex_subpat();
// issue #8492
let _ = match s {
Some(string) => string.len(),
None => 1,
};
let _ = match Some(10) {
Some(a) => a + 1,
None => 5,
};
let res: Result<i32, i32> = Ok(5);
let _ = match res {
Ok(a) => a + 1,
_ => 1,
};
let _ = match res {
Err(_) => 1,
Ok(a) => a + 1,
};
let _ = if let Ok(a) = res { a + 1 } else { 5 };
}
#[allow(dead_code)]
fn issue9742() -> Option<&'static str> {
// should not lint because of guards
match Some("foo ") {
Some(name) if name.starts_with("foo") => Some(name.trim()),
_ => None,
}
}
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