use expect_test::expect; use test_utils::mark; use super::{check_infer, check_infer_with_mismatches}; #[test] fn infer_block_expr_type_mismatch() { check_infer( r" fn test() { let a: i32 = { 1i64 }; } ", expect![[r" 10..40 '{ ...4 }; }': () 20..21 'a': i32 29..37 '{ 1i64 }': i64 31..35 '1i64': i64 "]], ); } #[test] fn coerce_places() { check_infer( r#" struct S<T> { a: T } fn f<T>(_: &[T]) -> T { loop {} } fn g<T>(_: S<&[T]>) -> T { loop {} } fn gen<T>() -> *mut [T; 2] { loop {} } fn test1<U>() -> *mut [U] { gen() } fn test2() { let arr: &[u8; 1] = &[1]; let a: &[_] = arr; let b = f(arr); let c: &[_] = { arr }; let d = g(S { a: arr }); let e: [&[_]; 1] = [arr]; let f: [&[_]; 2] = [arr; 2]; let g: (&[_], &[_]) = (arr, arr); } #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T: ?Sized> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<'a, 'b: 'a, T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<&'a U> for &'b T {} impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<*mut U> for *mut T {} "#, expect![[r" 30..31 '_': &[T] 44..55 '{ loop {} }': T 46..53 'loop {}': ! 51..53 '{}': () 64..65 '_': S<&[T]> 81..92 '{ loop {} }': T 83..90 'loop {}': ! 88..90 '{}': () 121..132 '{ loop {} }': *mut [T; _] 123..130 'loop {}': ! 128..130 '{}': () 159..172 '{ gen() }': *mut [U] 165..168 'gen': fn gen<U>() -> *mut [U; _] 165..170 'gen()': *mut [U; _] 185..419 '{ ...rr); }': () 195..198 'arr': &[u8; _] 211..215 '&[1]': &[u8; _] 212..215 '[1]': [u8; _] 213..214 '1': u8 226..227 'a': &[u8] 236..239 'arr': &[u8; _] 249..250 'b': u8 253..254 'f': fn f<u8>(&[u8]) -> u8 253..259 'f(arr)': u8 255..258 'arr': &[u8; _] 269..270 'c': &[u8] 279..286 '{ arr }': &[u8] 281..284 'arr': &[u8; _] 296..297 'd': u8 300..301 'g': fn g<u8>(S<&[u8]>) -> u8 300..315 'g(S { a: arr })': u8 302..314 'S { a: arr }': S<&[u8]> 309..312 'arr': &[u8; _] 325..326 'e': [&[u8]; _] 340..345 '[arr]': [&[u8]; _] 341..344 'arr': &[u8; _] 355..356 'f': [&[u8]; _] 370..378 '[arr; 2]': [&[u8]; _] 371..374 'arr': &[u8; _] 376..377 '2': usize 388..389 'g': (&[u8], &[u8]) 406..416 '(arr, arr)': (&[u8], &[u8]) 407..410 'arr': &[u8; _] 412..415 'arr': &[u8; _] "]], ); } #[test] fn infer_let_stmt_coerce() { check_infer( r" fn test() { let x: &[isize] = &[1]; let x: *const [isize] = &[1]; } ", expect![[r" 10..75 '{ ...[1]; }': () 20..21 'x': &[isize] 34..38 '&[1]': &[isize; _] 35..38 '[1]': [isize; _] 36..37 '1': isize 48..49 'x': *const [isize] 68..72 '&[1]': &[isize; _] 69..72 '[1]': [isize; _] 70..71 '1': isize "]], ); } #[test] fn infer_custom_coerce_unsized() { check_infer( r#" struct A<T: ?Sized>(*const T); struct B<T: ?Sized>(*const T); struct C<T: ?Sized> { inner: *const T } impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<B<U>> for B<T> {} impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<C<U>> for C<T> {} fn foo1<T>(x: A<[T]>) -> A<[T]> { x } fn foo2<T>(x: B<[T]>) -> B<[T]> { x } fn foo3<T>(x: C<[T]>) -> C<[T]> { x } fn test(a: A<[u8; 2]>, b: B<[u8; 2]>, c: C<[u8; 2]>) { let d = foo1(a); let e = foo2(b); let f = foo3(c); } #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T: ?Sized> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<'a, 'b: 'a, T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<&'a U> for &'b T {} impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<*mut U> for *mut T {} "#, expect![[r" 257..258 'x': A<[T]> 278..283 '{ x }': A<[T]> 280..281 'x': A<[T]> 295..296 'x': B<[T]> 316..321 '{ x }': B<[T]> 318..319 'x': B<[T]> 333..334 'x': C<[T]> 354..359 '{ x }': C<[T]> 356..357 'x': C<[T]> 369..370 'a': A<[u8; _]> 384..385 'b': B<[u8; _]> 399..400 'c': C<[u8; _]> 414..480 '{ ...(c); }': () 424..425 'd': A<[{unknown}]> 428..432 'foo1': fn foo1<{unknown}>(A<[{unknown}]>) -> A<[{unknown}]> 428..435 'foo1(a)': A<[{unknown}]> 433..434 'a': A<[u8; _]> 445..446 'e': B<[u8]> 449..453 'foo2': fn foo2<u8>(B<[u8]>) -> B<[u8]> 449..456 'foo2(b)': B<[u8]> 454..455 'b': B<[u8; _]> 466..467 'f': C<[u8]> 470..474 'foo3': fn foo3<u8>(C<[u8]>) -> C<[u8]> 470..477 'foo3(c)': C<[u8]> 475..476 'c': C<[u8; _]> "]], ); } #[test] fn infer_if_coerce() { check_infer( r#" fn foo<T>(x: &[T]) -> &[T] { loop {} } fn test() { let x = if true { foo(&[1]) } else { &[1] }; } #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T: ?Sized> {} "#, expect![[r" 10..11 'x': &[T] 27..38 '{ loop {} }': &[T] 29..36 'loop {}': ! 34..36 '{}': () 49..125 '{ ... }; }': () 59..60 'x': &[i32] 63..122 'if tru... }': &[i32] 66..70 'true': bool 71..96 '{ ... }': &[i32] 81..84 'foo': fn foo<i32>(&[i32]) -> &[i32] 81..90 'foo(&[1])': &[i32] 85..89 '&[1]': &[i32; _] 86..89 '[1]': [i32; _] 87..88 '1': i32 102..122 '{ ... }': &[i32; _] 112..116 '&[1]': &[i32; _] 113..116 '[1]': [i32; _] 114..115 '1': i32 "]], ); } #[test] fn infer_if_else_coerce() { check_infer( r#" fn foo<T>(x: &[T]) -> &[T] { loop {} } fn test() { let x = if true { &[1] } else { foo(&[1]) }; } #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T: ?Sized> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<'a, 'b: 'a, T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<&'a U> for &'b T {} impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<*mut U> for *mut T {} "#, expect![[r" 10..11 'x': &[T] 27..38 '{ loop {} }': &[T] 29..36 'loop {}': ! 34..36 '{}': () 49..125 '{ ... }; }': () 59..60 'x': &[i32] 63..122 'if tru... }': &[i32] 66..70 'true': bool 71..91 '{ ... }': &[i32; _] 81..85 '&[1]': &[i32; _] 82..85 '[1]': [i32; _] 83..84 '1': i32 97..122 '{ ... }': &[i32] 107..110 'foo': fn foo<i32>(&[i32]) -> &[i32] 107..116 'foo(&[1])': &[i32] 111..115 '&[1]': &[i32; _] 112..115 '[1]': [i32; _] 113..114 '1': i32 "]], ) } #[test] fn infer_match_first_coerce() { check_infer( r#" fn foo<T>(x: &[T]) -> &[T] { loop {} } fn test(i: i32) { let x = match i { 2 => foo(&[2]), 1 => &[1], _ => &[3], }; } #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T: ?Sized> {} "#, expect![[r" 10..11 'x': &[T] 27..38 '{ loop {} }': &[T] 29..36 'loop {}': ! 34..36 '{}': () 47..48 'i': i32 55..149 '{ ... }; }': () 65..66 'x': &[i32] 69..146 'match ... }': &[i32] 75..76 'i': i32 87..88 '2': i32 87..88 '2': i32 92..95 'foo': fn foo<i32>(&[i32]) -> &[i32] 92..101 'foo(&[2])': &[i32] 96..100 '&[2]': &[i32; _] 97..100 '[2]': [i32; _] 98..99 '2': i32 111..112 '1': i32 111..112 '1': i32 116..120 '&[1]': &[i32; _] 117..120 '[1]': [i32; _] 118..119 '1': i32 130..131 '_': i32 135..139 '&[3]': &[i32; _] 136..139 '[3]': [i32; _] 137..138 '3': i32 "]], ); } #[test] fn infer_match_second_coerce() { check_infer( r#" fn foo<T>(x: &[T]) -> &[T] { loop {} } fn test(i: i32) { let x = match i { 1 => &[1], 2 => foo(&[2]), _ => &[3], }; } #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T: ?Sized> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<'a, 'b: 'a, T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<&'a U> for &'b T {} impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<*mut U> for *mut T {} "#, expect![[r" 10..11 'x': &[T] 27..38 '{ loop {} }': &[T] 29..36 'loop {}': ! 34..36 '{}': () 47..48 'i': i32 55..149 '{ ... }; }': () 65..66 'x': &[i32] 69..146 'match ... }': &[i32] 75..76 'i': i32 87..88 '1': i32 87..88 '1': i32 92..96 '&[1]': &[i32; _] 93..96 '[1]': [i32; _] 94..95 '1': i32 106..107 '2': i32 106..107 '2': i32 111..114 'foo': fn foo<i32>(&[i32]) -> &[i32] 111..120 'foo(&[2])': &[i32] 115..119 '&[2]': &[i32; _] 116..119 '[2]': [i32; _] 117..118 '2': i32 130..131 '_': i32 135..139 '&[3]': &[i32; _] 136..139 '[3]': [i32; _] 137..138 '3': i32 "]], ); } #[test] fn coerce_merge_one_by_one1() { mark::check!(coerce_merge_fail_fallback); check_infer( r" fn test() { let t = &mut 1; let x = match 1 { 1 => t as *mut i32, 2 => t as &i32, _ => t as *const i32, }; } ", expect![[r" 10..144 '{ ... }; }': () 20..21 't': &mut i32 24..30 '&mut 1': &mut i32 29..30 '1': i32 40..41 'x': *const i32 44..141 'match ... }': *const i32 50..51 '1': i32 62..63 '1': i32 62..63 '1': i32 67..68 't': &mut i32 67..80 't as *mut i32': *mut i32 90..91 '2': i32 90..91 '2': i32 95..96 't': &mut i32 95..104 't as &i32': &i32 114..115 '_': i32 119..120 't': &mut i32 119..134 't as *const i32': *const i32 "]], ); } #[test] fn return_coerce_unknown() { check_infer_with_mismatches( r" fn foo() -> u32 { return unknown; } ", expect![[r" 16..39 '{ ...own; }': u32 22..36 'return unknown': ! 29..36 'unknown': u32 "]], ); } #[test] fn coerce_autoderef() { check_infer_with_mismatches( r" struct Foo; fn takes_ref_foo(x: &Foo) {} fn test() { takes_ref_foo(&Foo); takes_ref_foo(&&Foo); takes_ref_foo(&&&Foo); } ", expect![[r" 29..30 'x': &Foo 38..40 '{}': () 51..132 '{ ...oo); }': () 57..70 'takes_ref_foo': fn takes_ref_foo(&Foo) 57..76 'takes_...(&Foo)': () 71..75 '&Foo': &Foo 72..75 'Foo': Foo 82..95 'takes_ref_foo': fn takes_ref_foo(&Foo) 82..102 'takes_...&&Foo)': () 96..101 '&&Foo': &&Foo 97..101 '&Foo': &Foo 98..101 'Foo': Foo 108..121 'takes_ref_foo': fn takes_ref_foo(&Foo) 108..129 'takes_...&&Foo)': () 122..128 '&&&Foo': &&&Foo 123..128 '&&Foo': &&Foo 124..128 '&Foo': &Foo 125..128 'Foo': Foo "]], ); } #[test] fn coerce_autoderef_generic() { check_infer_with_mismatches( r" struct Foo; fn takes_ref<T>(x: &T) -> T { *x } fn test() { takes_ref(&Foo); takes_ref(&&Foo); takes_ref(&&&Foo); } ", expect![[r" 28..29 'x': &T 40..46 '{ *x }': T 42..44 '*x': T 43..44 'x': &T 57..126 '{ ...oo); }': () 63..72 'takes_ref': fn takes_ref<Foo>(&Foo) -> Foo 63..78 'takes_ref(&Foo)': Foo 73..77 '&Foo': &Foo 74..77 'Foo': Foo 84..93 'takes_ref': fn takes_ref<&Foo>(&&Foo) -> &Foo 84..100 'takes_...&&Foo)': &Foo 94..99 '&&Foo': &&Foo 95..99 '&Foo': &Foo 96..99 'Foo': Foo 106..115 'takes_ref': fn takes_ref<&&Foo>(&&&Foo) -> &&Foo 106..123 'takes_...&&Foo)': &&Foo 116..122 '&&&Foo': &&&Foo 117..122 '&&Foo': &&Foo 118..122 '&Foo': &Foo 119..122 'Foo': Foo "]], ); } #[test] fn coerce_autoderef_block() { check_infer_with_mismatches( r#" struct String {} #[lang = "deref"] trait Deref { type Target; } impl Deref for String { type Target = str; } fn takes_ref_str(x: &str) {} fn returns_string() -> String { loop {} } fn test() { takes_ref_str(&{ returns_string() }); } "#, expect![[r" 126..127 'x': &str 135..137 '{}': () 168..179 '{ loop {} }': String 170..177 'loop {}': ! 175..177 '{}': () 190..235 '{ ... }); }': () 196..209 'takes_ref_str': fn takes_ref_str(&str) 196..232 'takes_...g() })': () 210..231 '&{ ret...ng() }': &String 211..231 '{ retu...ng() }': String 213..227 'returns_string': fn returns_string() -> String 213..229 'return...ring()': String "]], ); } #[test] fn closure_return_coerce() { check_infer_with_mismatches( r" fn foo() { let x = || { if true { return &1u32; } &&1u32 }; } ", expect![[r" 9..105 '{ ... }; }': () 19..20 'x': || -> &u32 23..102 '|| { ... }': || -> &u32 26..102 '{ ... }': &u32 36..81 'if tru... }': () 39..43 'true': bool 44..81 '{ ... }': () 58..70 'return &1u32': ! 65..70 '&1u32': &u32 66..70 '1u32': u32 90..96 '&&1u32': &&u32 91..96 '&1u32': &u32 92..96 '1u32': u32 "]], ); } #[test] fn coerce_fn_item_to_fn_ptr() { check_infer_with_mismatches( r" fn foo(x: u32) -> isize { 1 } fn test() { let f: fn(u32) -> isize = foo; } ", expect![[r" 7..8 'x': u32 24..29 '{ 1 }': isize 26..27 '1': isize 40..78 '{ ...foo; }': () 50..51 'f': fn(u32) -> isize 72..75 'foo': fn foo(u32) -> isize "]], ); } #[test] fn coerce_fn_items_in_match_arms() { mark::check!(coerce_fn_reification); check_infer_with_mismatches( r" fn foo1(x: u32) -> isize { 1 } fn foo2(x: u32) -> isize { 2 } fn foo3(x: u32) -> isize { 3 } fn test() { let x = match 1 { 1 => foo1, 2 => foo2, _ => foo3, }; } ", expect![[r" 8..9 'x': u32 25..30 '{ 1 }': isize 27..28 '1': isize 39..40 'x': u32 56..61 '{ 2 }': isize 58..59 '2': isize 70..71 'x': u32 87..92 '{ 3 }': isize 89..90 '3': isize 103..192 '{ ... }; }': () 113..114 'x': fn(u32) -> isize 117..189 'match ... }': fn(u32) -> isize 123..124 '1': i32 135..136 '1': i32 135..136 '1': i32 140..144 'foo1': fn foo1(u32) -> isize 154..155 '2': i32 154..155 '2': i32 159..163 'foo2': fn foo2(u32) -> isize 173..174 '_': i32 178..182 'foo3': fn foo3(u32) -> isize "]], ); } #[test] fn coerce_closure_to_fn_ptr() { check_infer_with_mismatches( r" fn test() { let f: fn(u32) -> isize = |x| { 1 }; } ", expect![[r" 10..54 '{ ...1 }; }': () 20..21 'f': fn(u32) -> isize 42..51 '|x| { 1 }': |u32| -> isize 43..44 'x': u32 46..51 '{ 1 }': isize 48..49 '1': isize "]], ); } #[test] fn coerce_placeholder_ref() { // placeholders should unify, even behind references check_infer_with_mismatches( r" struct S<T> { t: T } impl<TT> S<TT> { fn get(&self) -> &TT { &self.t } } ", expect![[r" 50..54 'self': &S<TT> 63..86 '{ ... }': &TT 73..80 '&self.t': &TT 74..78 'self': &S<TT> 74..80 'self.t': TT "]], ); } #[test] fn coerce_unsize_array() { check_infer_with_mismatches( r#" #[lang = "unsize"] pub trait Unsize<T> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<T: Unsize<U>, U> CoerceUnsized<&U> for &T {} fn test() { let f: &[usize] = &[1, 2, 3]; } "#, expect![[r" 161..198 '{ ... 3]; }': () 171..172 'f': &[usize] 185..195 '&[1, 2, 3]': &[usize; _] 186..195 '[1, 2, 3]': [usize; _] 187..188 '1': usize 190..191 '2': usize 193..194 '3': usize "]], ); } #[test] fn coerce_unsize_trait_object_simple() { check_infer_with_mismatches( r#" #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<T: Unsize<U>, U> CoerceUnsized<&U> for &T {} trait Foo<T, U> {} trait Bar<U, T, X>: Foo<T, U> {} trait Baz<T, X>: Bar<usize, T, X> {} struct S<T, X>; impl<T, X> Foo<T, usize> for S<T, X> {} impl<T, X> Bar<usize, T, X> for S<T, X> {} impl<T, X> Baz<T, X> for S<T, X> {} fn test() { let obj: &dyn Baz<i8, i16> = &S; let obj: &dyn Bar<_, i8, i16> = &S; let obj: &dyn Foo<i8, _> = &S; } "#, expect![[r" 424..539 '{ ... &S; }': () 434..437 'obj': &dyn Baz<i8, i16> 459..461 '&S': &S<i8, i16> 460..461 'S': S<i8, i16> 471..474 'obj': &dyn Bar<usize, i8, i16> 499..501 '&S': &S<i8, i16> 500..501 'S': S<i8, i16> 511..514 'obj': &dyn Foo<i8, usize> 534..536 '&S': &S<i8, {unknown}> 535..536 'S': S<i8, {unknown}> "]], ); } #[test] // The rust reference says this should be possible, but rustc doesn't implement // it. We used to support it, but Chalk doesn't. #[ignore] fn coerce_unsize_trait_object_to_trait_object() { check_infer_with_mismatches( r#" #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<T: Unsize<U>, U> CoerceUnsized<&U> for &T {} trait Foo<T, U> {} trait Bar<U, T, X>: Foo<T, U> {} trait Baz<T, X>: Bar<usize, T, X> {} struct S<T, X>; impl<T, X> Foo<T, usize> for S<T, X> {} impl<T, X> Bar<usize, T, X> for S<T, X> {} impl<T, X> Baz<T, X> for S<T, X> {} fn test() { let obj: &dyn Baz<i8, i16> = &S; let obj: &dyn Bar<_, _, _> = obj; let obj: &dyn Foo<_, _> = obj; let obj2: &dyn Baz<i8, i16> = &S; let _: &dyn Foo<_, _> = obj2; } "#, expect![[r" 424..609 '{ ...bj2; }': () 434..437 'obj': &dyn Baz<i8, i16> 459..461 '&S': &S<i8, i16> 460..461 'S': S<i8, i16> 471..474 'obj': &dyn Bar<usize, i8, i16> 496..499 'obj': &dyn Baz<i8, i16> 509..512 'obj': &dyn Foo<i8, usize> 531..534 'obj': &dyn Bar<usize, i8, i16> 544..548 'obj2': &dyn Baz<i8, i16> 570..572 '&S': &S<i8, i16> 571..572 'S': S<i8, i16> 582..583 '_': &dyn Foo<i8, usize> 602..606 'obj2': &dyn Baz<i8, i16> "]], ); } #[test] fn coerce_unsize_super_trait_cycle() { check_infer_with_mismatches( r#" #[lang = "sized"] pub trait Sized {} #[lang = "unsize"] pub trait Unsize<T> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<T: Unsize<U>, U> CoerceUnsized<&U> for &T {} trait A {} trait B: C + A {} trait C: B {} trait D: C struct S; impl A for S {} impl B for S {} impl C for S {} impl D for S {} fn test() { let obj: &dyn D = &S; let obj: &dyn A = &S; } "#, expect![[r" 328..383 '{ ... &S; }': () 338..341 'obj': &dyn D 352..354 '&S': &S 353..354 'S': S 364..367 'obj': &dyn A 378..380 '&S': &S 379..380 'S': S "]], ); } #[ignore] #[test] fn coerce_unsize_generic() { // FIXME: Implement this // https://doc.rust-lang.org/reference/type-coercions.html#unsized-coercions check_infer_with_mismatches( r#" #[lang = "unsize"] pub trait Unsize<T> {} #[lang = "coerce_unsized"] pub trait CoerceUnsized<T> {} impl<T: Unsize<U>, U> CoerceUnsized<&U> for &T {} struct Foo<T> { t: T }; struct Bar<T>(Foo<T>); fn test() { let _: &Foo<[usize]> = &Foo { t: [1, 2, 3] }; let _: &Bar<[usize]> = &Bar(Foo { t: [1, 2, 3] }); } "#, expect![[r" "]], ); }