[rustc.git] / src / test / ui / typeck / typeck_type_placeholder_item.rs

// Needed for `type Y = impl Trait<_>` and `type B = _;`
#![feature(associated_type_defaults)]
// revisions: min_tait full_tait
#![feature(min_type_alias_impl_trait)]
#![cfg_attr(full_tait, feature(type_alias_impl_trait))]
//[full_tait]~^ WARN incomplete
// This test checks that it is not possible to enable global type
// inference by using the `_` type placeholder.

fn test() -> _ { 5 }
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

fn test2() -> (_, _) { (5, 5) }
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

static TEST3: _ = "test";
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

static TEST4: _ = 145;
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

static TEST5: (_, _) = (1, 2);
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

fn test6(_: _) { }
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

fn test6_b<T>(_: _, _: T) { }
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

fn test6_c<T, K, L, A, B>(_: _, _: (T, K, L, A, B)) { }
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

fn test7(x: _) { let _x: usize = x; }
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

fn test8(_f: fn() -> _) { }
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
//~^^ ERROR the type placeholder `_` is not allowed within types on item signatures

struct Test9;

impl Test9 {
    fn test9(&self) -> _ { () }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    fn test10(&self, _x : _) { }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
}

fn test11(x: &usize) -> &_ {
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    &x
}

unsafe fn test12(x: *const usize) -> *const *const _ {
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    &x
}

impl Clone for Test9 {
    fn clone(&self) -> _ { Test9 }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    fn clone_from(&mut self, other: _) { *self = Test9; }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
}

struct Test10 {
    a: _,
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    b: (_, _),
}

pub fn main() {
    static A = 42;
    //~^ ERROR missing type for `static` item
    static B: _ = 42;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    static C: Option<_> = Some(42);
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    fn fn_test() -> _ { 5 }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    fn fn_test2() -> (_, _) { (5, 5) }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    static FN_TEST3: _ = "test";
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    static FN_TEST4: _ = 145;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    static FN_TEST5: (_, _) = (1, 2);
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    fn fn_test6(_: _) { }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    fn fn_test7(x: _) { let _x: usize = x; }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    fn fn_test8(_f: fn() -> _) { }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    //~^^ ERROR the type placeholder `_` is not allowed within types on item signatures

    struct FnTest9;

    impl FnTest9 {
        fn fn_test9(&self) -> _ { () }
        //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

        fn fn_test10(&self, _x : _) { }
        //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    }

    impl Clone for FnTest9 {
        fn clone(&self) -> _ { FnTest9 }
        //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

        fn clone_from(&mut self, other: _) { *self = FnTest9; }
        //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    }

    struct FnTest10 {
        a: _,
        //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
        b: (_, _),
    }

    fn fn_test11(_: _) -> (_, _) { panic!() }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    //~| ERROR type annotations needed

    fn fn_test12(x: i32) -> (_, _) { (x, x) }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures

    fn fn_test13(x: _) -> (i32, _) { (x, x) }
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
}

trait T {
    fn method_test1(&self, x: _);
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    fn method_test2(&self, x: _) -> _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    fn method_test3(&self) -> _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    fn assoc_fn_test1(x: _);
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    fn assoc_fn_test2(x: _) -> _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    fn assoc_fn_test3() -> _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
}

struct BadStruct<_>(_);
//~^ ERROR expected identifier, found reserved identifier `_`
//~| ERROR the type placeholder `_` is not allowed within types on item signatures
trait BadTrait<_> {}
//~^ ERROR expected identifier, found reserved identifier `_`
impl BadTrait<_> for BadStruct<_> {}
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

fn impl_trait() -> impl BadTrait<_> {
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    unimplemented!()
}

struct BadStruct1<_, _>(_);
//~^ ERROR expected identifier, found reserved identifier `_`
//~| ERROR expected identifier, found reserved identifier `_`
//~| ERROR the name `_` is already used
//~| ERROR the type placeholder `_` is not allowed within types on item signatures
struct BadStruct2<_, T>(_, T);
//~^ ERROR expected identifier, found reserved identifier `_`
//~| ERROR the type placeholder `_` is not allowed within types on item signatures

type X = Box<_>;
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures

struct Struct;
trait Trait<T> {}
impl Trait<usize> for Struct {}
type Y = impl Trait<_>;
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
fn foo() -> Y {
    Struct
}

trait Qux {
    type A;
    type B = _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    const C: _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    const D: _ = 42;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    // type E: _; // FIXME: make the parser propagate the existence of `B`
    type F: std::ops::Fn(_);
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
}
impl Qux for Struct {
    type A = _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    type B = _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    const C: _;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    //~| ERROR associated constant in `impl` without body
    const D: _ = 42;
    //~^ ERROR the type placeholder `_` is not allowed within types on item signatures
}

fn map<T>(_: fn() -> Option<&'static T>) -> Option<T> {
    None
}

fn value() -> Option<&'static _> {
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
    Option::<&'static u8>::None
}

const _: Option<_> = map(value);
//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
Commit	Line	Data
74b04a01	1	// Needed for `type Y = impl Trait<_>` and `type B = _;`
6a06907d XL	2	#![feature(associated_type_defaults)]
	3	// revisions: min_tait full_tait
	4	#![feature(min_type_alias_impl_trait)]
	5	#![cfg_attr(full_tait, feature(type_alias_impl_trait))]
	6	//[full_tait]~^ WARN incomplete
74b04a01 XL	7	// This test checks that it is not possible to enable global type
	8	// inference by using the `_` type placeholder.
	9
	10	fn test() -> _ { 5 }
	11	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	12
	13	fn test2() -> (_, _) { (5, 5) }
	14	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	15
	16	static TEST3: _ = "test";
	17	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	18
	19	static TEST4: _ = 145;
	20	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	21
	22	static TEST5: (_, _) = (1, 2);
	23	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	24
	25	fn test6(_: _) { }
	26	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	27
	28	fn test6_b<T>(_: _, _: T) { }
	29	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	30
	31	fn test6_c<T, K, L, A, B>(_: _, _: (T, K, L, A, B)) { }
	32	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	33
	34	fn test7(x: _) { let _x: usize = x; }
	35	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	36
	37	fn test8(_f: fn() -> _) { }
	38	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
3dfed10e	39	//~^^ ERROR the type placeholder `_` is not allowed within types on item signatures
74b04a01 XL	40
	41	struct Test9;
	42
	43	impl Test9 {
	44	fn test9(&self) -> _ { () }
	45	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	46
	47	fn test10(&self, _x : _) { }
	48	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	49	}
	50
	51	fn test11(x: &usize) -> &_ {
	52	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	53	&x
	54	}
	55
	56	unsafe fn test12(x: const usize) -> const *const _ {
	57	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	58	&x
	59	}
	60
	61	impl Clone for Test9 {
	62	fn clone(&self) -> _ { Test9 }
	63	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	64
	65	fn clone_from(&mut self, other: _) { *self = Test9; }
	66	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	67	}
	68
	69	struct Test10 {
	70	a: _,
	71	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	72	b: (_, _),
	73	}
	74
	75	pub fn main() {
	76	static A = 42;
	77	//~^ ERROR missing type for `static` item
	78	static B: _ = 42;
	79	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	80	static C: Option<_> = Some(42);
	81	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	82
	83	fn fn_test() -> _ { 5 }
	84	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	85
	86	fn fn_test2() -> (_, _) { (5, 5) }
	87	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	88
	89	static FN_TEST3: _ = "test";
	90	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	91
	92	static FN_TEST4: _ = 145;
	93	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	94
	95	static FN_TEST5: (_, _) = (1, 2);
	96	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	97
	98	fn fn_test6(_: _) { }
	99	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	100
	101	fn fn_test7(x: _) { let _x: usize = x; }
	102	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	103
104	fn fn_test8(_f: fn() -> _) { }
105	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
3dfed10e	106	//~^^ ERROR the type placeholder `_` is not allowed within types on item signatures
74b04a01 XL	107
	108	struct FnTest9;
	109
	110	impl FnTest9 {
	111	fn fn_test9(&self) -> _ { () }
	112	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	113
	114	fn fn_test10(&self, _x : _) { }
	115	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	116	}
	117
	118	impl Clone for FnTest9 {
	119	fn clone(&self) -> _ { FnTest9 }
	120	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	121
	122	fn clone_from(&mut self, other: _) { *self = FnTest9; }
	123	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	124	}
	125
	126	struct FnTest10 {
	127	a: _,
	128	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	129	b: (_, _),
	130	}
	131
	132	fn fn_test11(_: _) -> (_, _) { panic!() }
	133	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	134	//~\| ERROR type annotations needed
	135
	136	fn fn_test12(x: i32) -> (_, _) { (x, x) }
	137	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	138
	139	fn fn_test13(x: _) -> (i32, _) { (x, x) }
	140	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	141	}
	142
	143	trait T {
	144	fn method_test1(&self, x: _);
	145	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	146	fn method_test2(&self, x: _) -> _;
	147	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	148	fn method_test3(&self) -> _;
	149	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	150	fn assoc_fn_test1(x: _);
	151	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	152	fn assoc_fn_test2(x: _) -> _;
	153	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	154	fn assoc_fn_test3() -> _;
	155	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	156	}
	157
	158	struct BadStruct<_>(_);
	159	//~^ ERROR expected identifier, found reserved identifier `_`
	160	//~\| ERROR the type placeholder `_` is not allowed within types on item signatures
	161	trait BadTrait<_> {}
	162	//~^ ERROR expected identifier, found reserved identifier `_`
	163	impl BadTrait<_> for BadStruct<_> {}
	164	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	165
	166	fn impl_trait() -> impl BadTrait<_> {
	167	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	168	unimplemented!()
	169	}
	170
171	struct BadStruct1<_, _>(_);
172	//~^ ERROR expected identifier, found reserved identifier `_`
173	//~\| ERROR expected identifier, found reserved identifier `_`
174	//~\| ERROR the name `_` is already used
175	//~\| ERROR the type placeholder `_` is not allowed within types on item signatures
176	struct BadStruct2<_, T>(_, T);
177	//~^ ERROR expected identifier, found reserved identifier `_`
178	//~\| ERROR the type placeholder `_` is not allowed within types on item signatures
179
180	type X = Box<_>;
181	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
182
183	struct Struct;
184	trait Trait<T> {}
185	impl Trait<usize> for Struct {}
186	type Y = impl Trait<_>;
187	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
188	fn foo() -> Y {
189	Struct
190	}
191
192	trait Qux {
193	type A;
194	type B = _;
195	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
196	const C: _;
197	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
198	const D: _ = 42;
199	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
200	// type E: _; // FIXME: make the parser propagate the existence of `B`
3dfed10e XL	201	type F: std::ops::Fn(_);
3dfed10e XL	202	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
74b04a01 XL	203	}
	204	impl Qux for Struct {
	205	type A = _;
	206	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	207	type B = _;
	208	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	209	const C: _;
	210	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	211	//~\| ERROR associated constant in `impl` without body
	212	const D: _ = 42;
	213	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	214	}
5869c6ff XL	215
	216	fn map<T>(_: fn() -> Option<&'static T>) -> Option<T> {
	217	None
	218	}
	219
	220	fn value() -> Option<&'static _> {
	221	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures
	222	Option::<&'static u8>::None
	223	}
	224
	225	const _: Option<_> = map(value);
	226	//~^ ERROR the type placeholder `_` is not allowed within types on item signatures