| // compile-flags: -Zdeduplicate-diagnostics=yes |
| |
| // This test of structural match checking enumerates the different kinds of |
| // const definitions, collecting cases where the const pattern is rejected. |
| // |
| // Note: Even if a non-structural-match type is part of an expression in a |
| // const's definition, that does not necessarily disqualify the const from being |
| // a match pattern: in principle, we just need the types involved in the final |
| // value to be structurally matchable. |
| |
| // See also RFC 1445 |
| |
| #![feature(type_ascription)] |
| #![warn(indirect_structural_match)] |
| //~^ NOTE lint level is defined here |
| |
| #[derive(Copy, Clone, Debug)] |
| struct NoPartialEq; |
| |
| #[derive(Copy, Clone, Debug)] |
| struct NoDerive; |
| |
| // This impl makes `NoDerive` irreflexive. |
| impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } } |
| |
| impl Eq for NoDerive { } |
| |
| type OND = Option<NoDerive>; |
| |
| struct TrivialEq(OND); |
| |
| // This impl makes `TrivialEq` trivial. |
| impl PartialEq for TrivialEq { fn eq(&self, _: &Self) -> bool { true } } |
| |
| impl Eq for TrivialEq { } |
| |
| fn main() { |
| #[derive(PartialEq, Eq, Debug)] |
| enum Derive<X> { Some(X), None, } |
| |
| const ENUM: Derive<NoDerive> = Derive::Some(NoDerive); |
| match Derive::Some(NoDerive) { ENUM => dbg!(ENUM), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| const FIELD: OND = TrivialEq(Some(NoDerive)).0; |
| match Some(NoDerive) { FIELD => dbg!(FIELD), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| const NO_DERIVE_SOME: OND = Some(NoDerive); |
| const INDIRECT: OND = NO_DERIVE_SOME; |
| match Some(NoDerive) {INDIRECT => dbg!(INDIRECT), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| const TUPLE: (OND, OND) = (None, Some(NoDerive)); |
| match (None, Some(NoDerive)) { TUPLE => dbg!(TUPLE), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| const TYPE_ASCRIPTION: OND = type_ascribe!(Some(NoDerive), OND); |
| match Some(NoDerive) { TYPE_ASCRIPTION => dbg!(TYPE_ASCRIPTION), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| const ARRAY: [OND; 2] = [None, Some(NoDerive)]; |
| match [None, Some(NoDerive)] { ARRAY => dbg!(ARRAY), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| const REPEAT: [OND; 2] = [Some(NoDerive); 2]; |
| match [Some(NoDerive); 2] { REPEAT => dbg!(REPEAT), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| trait Trait: Sized { const ASSOC: Option<Self>; } |
| impl Trait for NoDerive { const ASSOC: Option<NoDerive> = Some(NoDerive); } |
| match Some(NoDerive) { NoDerive::ASSOC => dbg!(NoDerive::ASSOC), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| const BLOCK: OND = { NoDerive; Some(NoDerive) }; |
| match Some(NoDerive) { BLOCK => dbg!(BLOCK), _ => panic!("whoops"), }; |
| //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| |
| const ADDR_OF: &OND = &Some(NoDerive); |
| match &Some(NoDerive) { ADDR_OF => dbg!(ADDR_OF), _ => panic!("whoops"), }; |
| //~^ WARN must be annotated with `#[derive(PartialEq, Eq)]` |
| //~| NOTE the traits must be derived |
| //~| NOTE StructuralEq.html for details |
| //~| WARN previously accepted by the compiler but is being phased out |
| //~| NOTE for more information, see issue #62411 |
| } |