139 lines
2.3 KiB
Rust
139 lines
2.3 KiB
Rust
#![warn(clippy::single_match)]
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fn dummy() {}
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fn single_match() {
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let x = Some(1u8);
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match x {
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Some(y) => {
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println!("{:?}", y);
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},
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_ => (),
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};
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let x = Some(1u8);
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match x {
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// Note the missing block braces.
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// We suggest `if let Some(y) = x { .. }` because the macro
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// is expanded before we can do anything.
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Some(y) => println!("{:?}", y),
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_ => (),
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}
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let z = (1u8, 1u8);
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match z {
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(2..=3, 7..=9) => dummy(),
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_ => {},
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};
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// Not linted (pattern guards used)
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match x {
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Some(y) if y == 0 => println!("{:?}", y),
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_ => (),
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}
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// Not linted (no block with statements in the single arm)
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match z {
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(2..=3, 7..=9) => println!("{:?}", z),
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_ => println!("nope"),
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}
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}
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enum Foo {
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Bar,
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Baz(u8),
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}
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use std::borrow::Cow;
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use Foo::*;
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fn single_match_know_enum() {
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let x = Some(1u8);
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let y: Result<_, i8> = Ok(1i8);
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match x {
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Some(y) => dummy(),
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None => (),
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};
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match y {
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Ok(y) => dummy(),
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Err(..) => (),
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};
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let c = Cow::Borrowed("");
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match c {
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Cow::Borrowed(..) => dummy(),
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Cow::Owned(..) => (),
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};
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let z = Foo::Bar;
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// no warning
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match z {
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Bar => println!("42"),
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Baz(_) => (),
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}
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match z {
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Baz(_) => println!("42"),
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Bar => (),
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}
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}
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fn issue_173() {
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let x = "test";
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match x {
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"test" => println!(),
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_ => (),
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}
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#[derive(PartialEq, Eq)]
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enum Foo {
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A,
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B,
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C(u32),
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}
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let x = Foo::A;
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match x {
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Foo::A => println!(),
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_ => (),
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}
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const FOO_C: Foo = Foo::C(0);
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match x {
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FOO_C => println!(),
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_ => (),
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}
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enum Bar {
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A,
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B,
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}
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impl PartialEq for Bar {
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fn eq(&self, rhs: &Self) -> bool {
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matches!((self, rhs), (Self::A, Self::A) | (Self::B, Self::B))
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}
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}
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impl Eq for Bar {}
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let x = Bar::A;
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match x {
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Bar::A => println!(),
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_ => (),
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}
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}
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macro_rules! single_match {
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($num:literal) => {
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match $num {
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15 => println!("15"),
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_ => (),
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}
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};
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}
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fn main() {
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single_match!(5);
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}
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