#![feature(type_alias_impl_trait)] #![warn(clippy::new_ret_no_self)] #![allow(dead_code)] fn main() {} trait R { type Item; } trait Q { type Item; type Item2; } struct S; impl R for S { type Item = Self; } impl S { // should not trigger the lint pub fn new() -> impl R { S } } struct S2; impl R for S2 { type Item = Self; } impl S2 { // should not trigger the lint pub fn new(_: String) -> impl R { S2 } } struct S3; impl R for S3 { type Item = u32; } impl S3 { // should trigger the lint pub fn new(_: String) -> impl R { S3 } } struct S4; impl Q for S4 { type Item = u32; type Item2 = Self; } impl S4 { // should not trigger the lint pub fn new(_: String) -> impl Q { S4 } } struct T; impl T { // should not trigger lint pub fn new() -> Self { unimplemented!(); } } struct U; impl U { // should trigger lint pub fn new() -> u32 { unimplemented!(); } } struct V; impl V { // should trigger lint pub fn new(_: String) -> u32 { unimplemented!(); } } struct TupleReturnerOk; impl TupleReturnerOk { // should not trigger lint pub fn new() -> (Self, u32) { unimplemented!(); } } struct TupleReturnerOk2; impl TupleReturnerOk2 { // should not trigger lint (it doesn't matter which element in the tuple is Self) pub fn new() -> (u32, Self) { unimplemented!(); } } struct TupleReturnerOk3; impl TupleReturnerOk3 { // should not trigger lint (tuple can contain multiple Self) pub fn new() -> (Self, Self) { unimplemented!(); } } struct TupleReturnerBad; impl TupleReturnerBad { // should trigger lint pub fn new() -> (u32, u32) { unimplemented!(); } } struct MutPointerReturnerOk; impl MutPointerReturnerOk { // should not trigger lint pub fn new() -> *mut Self { unimplemented!(); } } struct ConstPointerReturnerOk2; impl ConstPointerReturnerOk2 { // should not trigger lint pub fn new() -> *const Self { unimplemented!(); } } struct MutPointerReturnerBad; impl MutPointerReturnerBad { // should trigger lint pub fn new() -> *mut V { unimplemented!(); } } struct GenericReturnerOk; impl GenericReturnerOk { // should not trigger lint pub fn new() -> Option { unimplemented!(); } } struct GenericReturnerBad; impl GenericReturnerBad { // should trigger lint pub fn new() -> Option { unimplemented!(); } } struct NestedReturnerOk; impl NestedReturnerOk { // should not trigger lint pub fn new() -> (Option, u32) { unimplemented!(); } } struct NestedReturnerOk2; impl NestedReturnerOk2 { // should not trigger lint pub fn new() -> ((Self, u32), u32) { unimplemented!(); } } struct NestedReturnerOk3; impl NestedReturnerOk3 { // should not trigger lint pub fn new() -> Option<(Self, u32)> { unimplemented!(); } } struct WithLifetime<'a> { cat: &'a str, } impl<'a> WithLifetime<'a> { // should not trigger the lint, because the lifetimes are different pub fn new<'b: 'a>(s: &'b str) -> WithLifetime<'b> { unimplemented!(); } } mod issue5435 { struct V; pub trait TraitRetSelf { // should not trigger lint fn new() -> Self; } pub trait TraitRet { // should trigger lint as we are in trait definition fn new() -> String; } pub struct StructRet; impl TraitRet for StructRet { // should not trigger lint as we are in the impl block fn new() -> String { unimplemented!(); } } pub trait TraitRet2 { // should trigger lint fn new(_: String) -> String; } trait TupleReturnerOk { // should not trigger lint fn new() -> (Self, u32) where Self: Sized, { unimplemented!(); } } trait TupleReturnerOk2 { // should not trigger lint (it doesn't matter which element in the tuple is Self) fn new() -> (u32, Self) where Self: Sized, { unimplemented!(); } } trait TupleReturnerOk3 { // should not trigger lint (tuple can contain multiple Self) fn new() -> (Self, Self) where Self: Sized, { unimplemented!(); } } trait TupleReturnerBad { // should trigger lint fn new() -> (u32, u32) { unimplemented!(); } } trait MutPointerReturnerOk { // should not trigger lint fn new() -> *mut Self where Self: Sized, { unimplemented!(); } } trait ConstPointerReturnerOk2 { // should not trigger lint fn new() -> *const Self where Self: Sized, { unimplemented!(); } } trait MutPointerReturnerBad { // should trigger lint fn new() -> *mut V { unimplemented!(); } } trait GenericReturnerOk { // should not trigger lint fn new() -> Option where Self: Sized, { unimplemented!(); } } trait NestedReturnerOk { // should not trigger lint fn new() -> (Option, u32) where Self: Sized, { unimplemented!(); } } trait NestedReturnerOk2 { // should not trigger lint fn new() -> ((Self, u32), u32) where Self: Sized, { unimplemented!(); } } trait NestedReturnerOk3 { // should not trigger lint fn new() -> Option<(Self, u32)> where Self: Sized, { unimplemented!(); } } } // issue #1724 struct RetOtherSelf(T); struct RetOtherSelfWrapper(T); impl RetOtherSelf { fn new(t: T) -> RetOtherSelf> { RetOtherSelf(RetOtherSelfWrapper(t)) } } mod issue7344 { struct RetImplTraitSelf(T); impl RetImplTraitSelf { // should not trigger lint fn new(t: T) -> impl Into { Self(t) } } struct RetImplTraitNoSelf(T); impl RetImplTraitNoSelf { // should trigger lint fn new(t: T) -> impl Into { 1 } } trait Trait2 {} impl Trait2 for () {} struct RetImplTraitSelf2(T); impl RetImplTraitSelf2 { // should not trigger lint fn new(t: T) -> impl Trait2<(), Self> { unimplemented!() } } struct RetImplTraitNoSelf2(T); impl RetImplTraitNoSelf2 { // should trigger lint fn new(t: T) -> impl Trait2<(), i32> { unimplemented!() } } struct RetImplTraitSelfAdt<'a>(&'a str); impl<'a> RetImplTraitSelfAdt<'a> { // should not trigger lint fn new<'b: 'a>(s: &'b str) -> impl Into> { RetImplTraitSelfAdt(s) } } } mod issue10041 { struct Bomb; impl Bomb { // Hidden default generic parameter. pub fn new() -> impl PartialOrd { 0i32 } } // TAIT with self-referencing bounds type X = impl std::ops::Add; struct Bomb2; impl Bomb2 { pub fn new() -> X { 0i32 } } }