src/libcoretest/option.rs

   1 // Copyright 2014 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 use core::option::*;
  12 use core::marker;
  13 use core::mem;
  14 use core::clone::Clone;
  15
  16 #[test]
  17 fn test_get_ptr() {
  18     unsafe {
  19         let x: Box<_> = box 0;
  20         let addr_x: *const isize = mem::transmute(&*x);
  21         let opt = Some(x);
  22         let y = opt.unwrap();
  23         let addr_y: *const isize = mem::transmute(&*y);
  24         assert_eq!(addr_x, addr_y);
  25     }
  26 }
  27
  28 #[test]
  29 fn test_get_str() {
  30     let x = "test".to_string();
  31     let addr_x = x.as_ptr();
  32     let opt = Some(x);
  33     let y = opt.unwrap();
  34     let addr_y = y.as_ptr();
  35     assert_eq!(addr_x, addr_y);
  36 }
  37
  38 #[test]
  39 fn test_get_resource() {
  40     use std::rc::Rc;
  41     use core::cell::RefCell;
  42
  43     struct R {
  44        i: Rc<RefCell<isize>>,
  45     }
  46
  47         impl Drop for R {
  48        fn drop(&mut self) {
  49             let ii = &*self.i;
  50             let i = *ii.borrow();
  51             *ii.borrow_mut() = i + 1;
  52         }
  53     }
  54
  55     fn r(i: Rc<RefCell<isize>>) -> R {
  56         R {
  57             i: i
  58         }
  59     }
  60
  61     let i = Rc::new(RefCell::new(0));
  62     {
  63         let x = r(i.clone());
  64         let opt = Some(x);
  65         let _y = opt.unwrap();
  66     }
  67     assert_eq!(*i.borrow(), 1);
  68 }
  69
  70 #[test]
  71 fn test_option_dance() {
  72     let x = Some(());
  73     let mut y = Some(5);
  74     let mut y2 = 0;
  75     for _x in x.iter() {
  76         y2 = y.take().unwrap();
  77     }
  78     assert_eq!(y2, 5);
  79     assert!(y.is_none());
  80 }
  81
  82 #[test] #[should_panic]
  83 fn test_option_too_much_dance() {
  84     let mut y = Some(marker::NoCopy);
  85     let _y2 = y.take().unwrap();
  86     let _y3 = y.take().unwrap();
  87 }
  88
  89 #[test]
  90 fn test_and() {
  91     let x: Option<isize> = Some(1);
  92     assert_eq!(x.and(Some(2)), Some(2));
  93     assert_eq!(x.and(None::<isize>), None);
  94
  95     let x: Option<isize> = None;
  96     assert_eq!(x.and(Some(2)), None);
  97     assert_eq!(x.and(None::<isize>), None);
  98 }
  99
 100 #[test]
 101 fn test_and_then() {
 102     let x: Option<isize> = Some(1);
 103     assert_eq!(x.and_then(|x| Some(x + 1)), Some(2));
 104     assert_eq!(x.and_then(|_| None::<isize>), None);
 105
 106     let x: Option<isize> = None;
 107     assert_eq!(x.and_then(|x| Some(x + 1)), None);
 108     assert_eq!(x.and_then(|_| None::<isize>), None);
 109 }
 110
 111 #[test]
 112 fn test_or() {
 113     let x: Option<isize> = Some(1);
 114     assert_eq!(x.or(Some(2)), Some(1));
 115     assert_eq!(x.or(None), Some(1));
 116
 117     let x: Option<isize> = None;
 118     assert_eq!(x.or(Some(2)), Some(2));
 119     assert_eq!(x.or(None), None);
 120 }
 121
 122 #[test]
 123 fn test_or_else() {
 124     let x: Option<isize> = Some(1);
 125     assert_eq!(x.or_else(|| Some(2)), Some(1));
 126     assert_eq!(x.or_else(|| None), Some(1));
 127
 128     let x: Option<isize> = None;
 129     assert_eq!(x.or_else(|| Some(2)), Some(2));
 130     assert_eq!(x.or_else(|| None), None);
 131 }
 132
 133 #[test]
 134 fn test_unwrap() {
 135     assert_eq!(Some(1).unwrap(), 1);
 136     let s = Some("hello".to_string()).unwrap();
 137     assert_eq!(s, "hello");
 138 }
 139
 140 #[test]
 141 #[should_panic]
 142 fn test_unwrap_panic1() {
 143     let x: Option<isize> = None;
 144     x.unwrap();
 145 }
 146
 147 #[test]
 148 #[should_panic]
 149 fn test_unwrap_panic2() {
 150     let x: Option<String> = None;
 151     x.unwrap();
 152 }
 153
 154 #[test]
 155 fn test_unwrap_or() {
 156     let x: Option<isize> = Some(1);
 157     assert_eq!(x.unwrap_or(2), 1);
 158
 159     let x: Option<isize> = None;
 160     assert_eq!(x.unwrap_or(2), 2);
 161 }
 162
 163 #[test]
 164 fn test_unwrap_or_else() {
 165     let x: Option<isize> = Some(1);
 166     assert_eq!(x.unwrap_or_else(|| 2), 1);
 167
 168     let x: Option<isize> = None;
 169     assert_eq!(x.unwrap_or_else(|| 2), 2);
 170 }
 171
 172 #[test]
 173 fn test_iter() {
 174     let val = 5;
 175
 176     let x = Some(val);
 177     let mut it = x.iter();
 178
 179     assert_eq!(it.size_hint(), (1, Some(1)));
 180     assert_eq!(it.next(), Some(&val));
 181     assert_eq!(it.size_hint(), (0, Some(0)));
 182     assert!(it.next().is_none());
 183 }
 184
 185 #[test]
 186 fn test_mut_iter() {
 187     let val = 5;
 188     let new_val = 11;
 189
 190     let mut x = Some(val);
 191     {
 192         let mut it = x.iter_mut();
 193
 194         assert_eq!(it.size_hint(), (1, Some(1)));
 195
 196         match it.next() {
 197             Some(interior) => {
 198                 assert_eq!(*interior, val);
 199                 *interior = new_val;
 200             }
 201             None => assert!(false),
 202         }
 203
 204         assert_eq!(it.size_hint(), (0, Some(0)));
 205         assert!(it.next().is_none());
 206     }
 207     assert_eq!(x, Some(new_val));
 208 }
 209
 210 #[test]
 211 fn test_ord() {
 212     let small = Some(1.0f64);
 213     let big = Some(5.0f64);
 214     let nan = Some(0.0f64/0.0);
 215     assert!(!(nan < big));
 216     assert!(!(nan > big));
 217     assert!(small < big);
 218     assert!(None < big);
 219     assert!(big > None);
 220 }
 221
 222 #[test]
 223 fn test_collect() {
 224     let v: Option<Vec<isize>> = (0..0).map(|_| Some(0)).collect();
 225     assert!(v == Some(vec![]));
 226
 227     let v: Option<Vec<isize>> = (0..3).map(|x| Some(x)).collect();
 228     assert!(v == Some(vec![0, 1, 2]));
 229
 230     let v: Option<Vec<isize>> = (0..3).map(|x| {
 231         if x > 1 { None } else { Some(x) }
 232     }).collect();
 233     assert!(v == None);
 234
 235     // test that it does not take more elements than it needs
 236     let mut functions: [Box<Fn() -> Option<()>>; 3] =
 237         [box || Some(()), box || None, box || panic!()];
 238
 239     let v: Option<Vec<()>> = functions.iter_mut().map(|f| (*f)()).collect();
 240
 241     assert!(v == None);
 242 }
 243
 244
 245 #[test]
 246 fn test_cloned() {
 247     let val = 1u32;
 248     let val_ref = &val;
 249     let opt_none: Option<&'static u32> = None;
 250     let opt_ref = Some(&val);
 251     let opt_ref_ref = Some(&val_ref);
 252
 253     // None works
 254     assert_eq!(opt_none.clone(), None);
 255     assert_eq!(opt_none.cloned(), None);
 256
 257     // Immutable ref works
 258     assert_eq!(opt_ref.clone(), Some(&val));
 259     assert_eq!(opt_ref.cloned(), Some(1u32));
 260
 261     // Double Immutable ref works
 262     assert_eq!(opt_ref_ref.clone(), Some(&val_ref));
 263     assert_eq!(opt_ref_ref.clone().cloned(), Some(&val));
 264     assert_eq!(opt_ref_ref.cloned().cloned(), Some(1u32));
 265 }