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|
//@run-rustfix
#![warn(clippy::needless_match)]
#![allow(clippy::manual_map)]
#![allow(dead_code)]
#[derive(Clone, Copy)]
enum Simple {
A,
B,
C,
D,
}
fn useless_match() {
let i = 10;
let _: i32 = i;
let s = "test";
let _: &str = s;
}
fn custom_type_match() {
let se = Simple::A;
let _: Simple = se;
// Don't trigger
let _: Simple = match se {
Simple::A => Simple::A,
Simple::B => Simple::B,
_ => Simple::C,
};
// Mingled, don't trigger
let _: Simple = match se {
Simple::A => Simple::B,
Simple::B => Simple::C,
Simple::C => Simple::D,
Simple::D => Simple::A,
};
}
fn option_match(x: Option<i32>) {
let _: Option<i32> = x;
// Don't trigger, this is the case for manual_map_option
let _: Option<i32> = match x {
Some(a) => Some(-a),
None => None,
};
}
fn func_ret_err<T>(err: T) -> Result<i32, T> {
Err(err)
}
fn result_match() {
let _: Result<i32, i32> = Ok(1);
let _: Result<i32, i32> = func_ret_err(0_i32);
// as ref, don't trigger
let res = &func_ret_err(0_i32);
let _: Result<&i32, &i32> = match *res {
Ok(ref x) => Ok(x),
Err(ref x) => Err(x),
};
}
fn if_let_option() {
let _ = Some(1);
fn do_something() {}
// Don't trigger
let _ = if let Some(a) = Some(1) {
Some(a)
} else {
do_something();
None
};
// Don't trigger
let _ = if let Some(a) = Some(1) {
do_something();
Some(a)
} else {
None
};
// Don't trigger
let _ = if let Some(a) = Some(1) { Some(a) } else { Some(2) };
}
fn if_let_option_result() -> Result<(), ()> {
fn f(x: i32) -> Result<Option<i32>, ()> {
Ok(Some(x))
}
// Don't trigger
let _ = if let Some(v) = f(1)? { Some(v) } else { f(2)? };
Ok(())
}
fn if_let_result() {
let x: Result<i32, i32> = Ok(1);
let _: Result<i32, i32> = x;
let _: Result<i32, i32> = x;
// Input type mismatch, don't trigger
#[allow(clippy::question_mark)]
let _: Result<i32, i32> = if let Err(e) = Ok(1) { Err(e) } else { x };
}
fn if_let_custom_enum(x: Simple) {
let _: Simple = x;
// Don't trigger
let _: Simple = if let Simple::A = x {
Simple::A
} else if true {
Simple::B
} else {
x
};
}
mod issue8542 {
#[derive(Clone, Copy)]
enum E {
VariantA(u8, u8),
VariantB(u8, bool),
}
enum Complex {
A(u8),
B(u8, bool),
C(u8, i32, f64),
D(E, bool),
}
fn match_test() {
let ce = Complex::B(8, false);
let aa = 0_u8;
let bb = false;
let _: Complex = ce;
// Don't trigger
let _: Complex = match ce {
Complex::A(_) => Complex::A(aa),
Complex::B(_, b) => Complex::B(aa, b),
Complex::C(_, b, _) => Complex::C(aa, b, 64_f64),
Complex::D(e, b) => Complex::D(e, b),
};
// Don't trigger
let _: Complex = match ce {
Complex::A(a) => Complex::A(a),
Complex::B(a, _) => Complex::B(a, bb),
Complex::C(a, _, _) => Complex::C(a, 32_i32, 64_f64),
_ => ce,
};
}
}
/// Lint triggered when type coercions happen.
/// Do NOT trigger on any of these.
mod issue8551 {
trait Trait {}
struct Struct;
impl Trait for Struct {}
fn optmap(s: Option<&Struct>) -> Option<&dyn Trait> {
match s {
Some(s) => Some(s),
None => None,
}
}
fn lint_tests() {
let option: Option<&Struct> = None;
let _: Option<&dyn Trait> = match option {
Some(s) => Some(s),
None => None,
};
let _: Option<&dyn Trait> = if true {
match option {
Some(s) => Some(s),
None => None,
}
} else {
None
};
let result: Result<&Struct, i32> = Err(0);
let _: Result<&dyn Trait, i32> = match result {
Ok(s) => Ok(s),
Err(e) => Err(e),
};
let _: Option<&dyn Trait> = if let Some(s) = option { Some(s) } else { None };
}
}
trait Tr {
fn as_mut(&mut self) -> Result<&mut i32, &mut i32>;
}
impl Tr for Result<i32, i32> {
fn as_mut(&mut self) -> Result<&mut i32, &mut i32> {
match self {
Ok(x) => Ok(x),
Err(e) => Err(e),
}
}
}
mod issue9084 {
fn wildcard_if() {
let mut some_bool = true;
let e = Some(1);
// should lint
let _ = e;
// should lint
let _ = e;
// should not lint
let _ = match e {
_ if some_bool => e,
_ => Some(2),
};
// should not lint
let _ = match e {
Some(i) => Some(i + 1),
_ if some_bool => e,
_ => e,
};
// should not lint (guard has side effects)
let _ = match e {
Some(i) => Some(i),
_ if {
some_bool = false;
some_bool
} =>
{
e
},
_ => e,
};
}
}
fn main() {}
|
