src/test/compile-fail/rfc1623.rs

   1 // Copyright 2012 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10 #![feature(static_in_const)]
  11 #![allow(dead_code)]
  12
  13 fn non_elidable<'a, 'b>(a: &'a u8, b: &'b u8) -> &'a u8 {
  14     a
  15 }
  16
  17 // the boundaries of elision
  18 static NON_ELIDABLE_FN: &fn(&u8, &u8) -> &u8 =
  19 //~^ ERROR missing lifetime specifier [E0106]
  20     &(non_elidable as fn(&u8, &u8) -> &u8);
  21     //~^ ERROR missing lifetime specifier [E0106]
  22
  23 struct SomeStruct<'x, 'y, 'z: 'x> {
  24     foo: &'x Foo<'z>,
  25     bar: &'x Bar<'z>,
  26     f: &'y for<'a, 'b: 'a> Fn(&'a Foo<'b>) -> &'a Bar<'b>,
  27 }
  28
  29 fn id<T>(t: T) -> T {
  30     t
  31 }
  32
  33 static SOME_STRUCT: &SomeStruct = SomeStruct {
  34     foo: &Foo { bools: &[false, true] },
  35     bar: &Bar { bools: &[true, true] },
  36     f: &id,
  37 };
  38
  39 // very simple test for a 'static static with default lifetime
  40 static STATIC_STR: &'static str = "&'static str";
  41 const CONST_STR: &'static str = "&'static str";
  42
  43 // this should be the same as without default:
  44 static EXPLICIT_STATIC_STR: &'static str = "&'static str";
  45 const EXPLICIT_CONST_STR: &'static str = "&'static str";
  46
  47 // a function that elides to an unbound lifetime for both in- and output
  48 fn id_u8_slice(arg: &[u8]) -> &[u8] {
  49     arg
  50 }
  51
  52 // one with a function, argument elided
  53 static STATIC_SIMPLE_FN: &'static fn(&[u8]) -> &[u8] = &(id_u8_slice as fn(&[u8]) -> &[u8]);
  54 const CONST_SIMPLE_FN: &'static fn(&[u8]) -> &[u8] = &(id_u8_slice as fn(&[u8]) -> &[u8]);
  55
  56 // this should be the same as without elision
  57 static STATIC_NON_ELIDED_fN: &'static for<'a> fn(&'a [u8]) -> &'a [u8] =
  58     &(id_u8_slice as for<'a> fn(&'a [u8]) -> &'a [u8]);
  59 const CONST_NON_ELIDED_fN: &'static for<'a> fn(&'a [u8]) -> &'a [u8] =
  60     &(id_u8_slice as for<'a> fn(&'a [u8]) -> &'a [u8]);
  61
  62 // another function that elides, each to a different unbound lifetime
  63 fn multi_args(a: &u8, b: &u8, c: &u8) {}
  64
  65 static STATIC_MULTI_FN: &'static fn(&u8, &u8, &u8) = &(multi_args as fn(&u8, &u8, &u8));
  66 const CONST_MULTI_FN: &'static fn(&u8, &u8, &u8) = &(multi_args as fn(&u8, &u8, &u8));
  67
  68 struct Foo<'a> {
  69     bools: &'a [bool],
  70 }
  71
  72 static STATIC_FOO: Foo<'static> = Foo { bools: &[true, false] };
  73 const CONST_FOO: Foo<'static> = Foo { bools: &[true, false] };
  74
  75 type Bar<'a> = Foo<'a>;
  76
  77 static STATIC_BAR: Bar<'static> = Bar { bools: &[true, false] };
  78 const CONST_BAR: Bar<'static> = Bar { bools: &[true, false] };
  79
  80 type Baz<'a> = fn(&'a [u8]) -> Option<u8>;
  81
  82 fn baz(e: &[u8]) -> Option<u8> {
  83     e.first().map(|x| *x)
  84 }
  85
  86 static STATIC_BAZ: &'static Baz<'static> = &(baz as Baz);
  87 const CONST_BAZ: &'static Baz<'static> = &(baz as Baz);
  88
  89 static BYTES: &'static [u8] = &[1, 2, 3];
  90
  91 fn main() {
  92     let x = &[1u8, 2, 3];
  93     let y = x;
  94
  95     // this works, so lifetime < `'static` is valid
  96     assert_eq!(Some(1), STATIC_BAZ(y));
  97     assert_eq!(Some(1), CONST_BAZ(y));
  98
  99     let y = &[1u8, 2, 3];
 100
 101     STATIC_BAZ(BYTES); // BYTES has static lifetime
 102     CONST_BAZ(y); // interestingly this does not get reported
 103 }