src/test/run-pass/cast-rfc0401.rs

   1 // Copyright 2015 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
  11 #![allow(dead_code)]
  12
  13 use std::vec;
  14
  15 enum Simple {
  16     A,
  17     B,
  18     C
  19 }
  20
  21 enum Valued {
  22     H8=163,
  23     Z=0,
  24     X=256,
  25     H7=67,
  26 }
  27
  28 enum ValuedSigned {
  29     M1=-1,
  30     P1=1
  31 }
  32
  33 fn main()
  34 {
  35     // coercion-cast
  36     let mut it = vec![137].into_iter();
  37     let itr: &mut vec::IntoIter<u32> = &mut it;
  38     assert_eq!((itr as &mut Iterator<Item=u32>).next(), Some(137));
  39     assert_eq!((itr as &mut Iterator<Item=u32>).next(), None);
  40
  41     assert_eq!(Some(4u32) as Option<u32>, Some(4u32));
  42     assert_eq!((1u32,2u32) as (u32,u32), (1,2));
  43
  44     // this isn't prim-int-cast. Check that it works.
  45     assert_eq!(false as bool, false);
  46     assert_eq!(true as bool, true);
  47
  48     // numeric-cast
  49     let l: u64 = 0x8090a0b0c0d0e0f0;
  50     let lsz: usize = l as usize;
  51     assert_eq!(l as u32, 0xc0d0e0f0);
  52
  53     // numeric-cast
  54     assert_eq!(l as u8, 0xf0);
  55     assert_eq!(l as i8,-0x10);
  56     assert_eq!(l as u32, 0xc0d0e0f0);
  57     assert_eq!(l as u32 as usize as u32, l as u32);
  58     assert_eq!(l as i32,-0x3f2f1f10);
  59     assert_eq!(l as i32 as isize as i32, l as i32);
  60     assert_eq!(l as i64,-0x7f6f5f4f3f2f1f10);
  61
  62     assert_eq!(0 as f64, 0f64);
  63     assert_eq!(1 as f64, 1f64);
  64
  65     assert_eq!(l as f64, 9264081114510712022f64);
  66
  67     assert_eq!(l as i64 as f64, -9182662959198838444f64);
  68 //  float overflow : needs fixing
  69 //  assert_eq!(l as f32 as i64 as u64, 9264082620822882088u64);
  70 //  assert_eq!(l as i64 as f32 as i64, 9182664080220408446i64);
  71
  72     assert_eq!(4294967040f32 as u32, 0xffffff00u32);
  73     assert_eq!(1.844674407370955e19f64 as u64, 0xfffffffffffff800u64);
  74
  75     assert_eq!(9.223372036854775e18f64 as i64, 0x7ffffffffffffc00i64);
  76     assert_eq!(-9.223372036854776e18f64 as i64, 0x8000000000000000u64 as i64);
  77
  78     // addr-ptr-cast/ptr-addr-cast (thin ptr)
  79     let p: *const [u8; 1] = lsz as *const [u8; 1];
  80     assert_eq!(p as usize, lsz);
  81
  82     // ptr-ptr-cast (thin ptr)
  83     let w: *const () = p as *const ();
  84     assert_eq!(w as usize, lsz);
  85
  86     // ptr-ptr-cast (fat->thin)
  87     let u: *const [u8] = unsafe{&*p};
  88     assert_eq!(u as *const u8, p as *const u8);
  89     assert_eq!(u as *const u16, p as *const u16);
  90
  91     // ptr-ptr-cast (Length vtables)
  92     let mut l : [u8; 2] = [0,1];
  93     let w: *mut [u16; 2] = &mut l as *mut [u8; 2] as *mut _;
  94     let w: *mut [u16] = unsafe {&mut *w};
  95     let w_u8 : *const [u8] = w as *const [u8];
  96     assert_eq!(unsafe{&*w_u8}, &l);
  97
  98     let s: *mut str = w as *mut str;
  99     let l_via_str = unsafe{&*(s as *const [u8])};
 100     assert_eq!(&l, l_via_str);
 101
 102     // ptr-ptr-cast (Length vtables, check length is preserved)
 103     let l: [[u8; 3]; 2] = [[3, 2, 6], [4, 5, 1]];
 104     let p: *const [[u8; 3]] = &l;
 105     let p: &[[u8; 2]] = unsafe {&*(p as *const [[u8; 2]])};
 106     assert_eq!(p, [[3, 2], [6, 4]]);
 107
 108     // enum-cast
 109     assert_eq!(Simple::A as u8, 0);
 110     assert_eq!(Simple::B as u8, 1);
 111
 112     assert_eq!(Valued::H8 as i8, -93);
 113     assert_eq!(Valued::H7 as i8, 67);
 114     assert_eq!(Valued::Z as i8, 0);
 115
 116     assert_eq!(Valued::H8 as u8, 163);
 117     assert_eq!(Valued::H7 as u8, 67);
 118     assert_eq!(Valued::Z as u8, 0);
 119
 120     assert_eq!(Valued::H8 as u16, 163);
 121     assert_eq!(Valued::Z as u16, 0);
 122     assert_eq!(Valued::H8 as u16, 163);
 123     assert_eq!(Valued::Z as u16, 0);
 124
 125     assert_eq!(ValuedSigned::M1 as u16, 65535);
 126     assert_eq!(ValuedSigned::M1 as i16, -1);
 127     assert_eq!(ValuedSigned::P1 as u16, 1);
 128     assert_eq!(ValuedSigned::P1 as i16, 1);
 129
 130     // prim-int-cast
 131     assert_eq!(false as u16, 0);
 132     assert_eq!(true as u16, 1);
 133     assert_eq!(false as i64, 0);
 134     assert_eq!(true as i64, 1);
 135     assert_eq!('a' as u32, 0x61);
 136     assert_eq!('a' as u16, 0x61);
 137     assert_eq!('a' as u8, 0x61);
 138     assert_eq!('א' as u8, 0xd0);
 139     assert_eq!('א' as u16, 0x5d0);
 140     assert_eq!('א' as u32, 0x5d0);
 141     assert_eq!('🐵' as u8, 0x35);
 142     assert_eq!('🐵' as u16, 0xf435);
 143     assert_eq!('🐵' as u32, 0x1f435);
 144     assert_eq!('英' as i16, -0x7d0f);
 145     assert_eq!('英' as u16, 0x82f1);
 146
 147     // u8-char-cast
 148     assert_eq!(0x61 as char, 'a');
 149     assert_eq!(0u8 as char, '\0');
 150     assert_eq!(0xd7 as char, '×');
 151
 152     // array-ptr-cast
 153     let x = [1,2,3];
 154     let first : *const u32 = &x[0];
 155
 156     assert_eq!(first, &x as *const _);
 157     assert_eq!(first, &x as *const u32);
 158
 159     // fptr-addr-cast
 160     fn foo() {
 161         println!("foo!");
 162     }
 163     fn bar() {
 164         println!("bar!");
 165     }
 166
 167     assert!(foo as usize != bar as usize);
 168
 169     assert_eq!(foo as i16, foo as usize as i16);
 170
 171     // fptr-ptr-cast
 172
 173     assert_eq!(foo as *const u8 as usize, foo as usize);
 174     assert!(foo as *const u32 != first);
 175 }
 176 fn foo() { }