1 use super::*;
2
3 #[test]
test_range()4 fn test_range() {
5 assert_eq!((0..5).collect::<Vec<_>>(), [0, 1, 2, 3, 4]);
6 assert_eq!((-10..-1).collect::<Vec<_>>(), [-10, -9, -8, -7, -6, -5, -4, -3, -2]);
7 assert_eq!((0..5).rev().collect::<Vec<_>>(), [4, 3, 2, 1, 0]);
8 assert_eq!((200..-5).count(), 0);
9 assert_eq!((200..-5).rev().count(), 0);
10 assert_eq!((200..200).count(), 0);
11 assert_eq!((200..200).rev().count(), 0);
12
13 assert_eq!((0..100).size_hint(), (100, Some(100)));
14 // this test is only meaningful when sizeof usize < sizeof u64
15 assert_eq!((usize::MAX - 1..usize::MAX).size_hint(), (1, Some(1)));
16 assert_eq!((-10..-1).size_hint(), (9, Some(9)));
17 assert_eq!((-1..-10).size_hint(), (0, Some(0)));
18
19 assert_eq!((-70..58).size_hint(), (128, Some(128)));
20 assert_eq!((-128..127).size_hint(), (255, Some(255)));
21 assert_eq!(
22 (-2..isize::MAX).size_hint(),
23 (isize::MAX as usize + 2, Some(isize::MAX as usize + 2))
24 );
25 }
26
27 #[test]
test_char_range()28 fn test_char_range() {
29 use std::char;
30 // Miri is too slow
31 let from = if cfg!(miri) { char::from_u32(0xD800 - 10).unwrap() } else { '\0' };
32 let to = if cfg!(miri) { char::from_u32(0xDFFF + 10).unwrap() } else { char::MAX };
33 assert!((from..=to).eq((from as u32..=to as u32).filter_map(char::from_u32)));
34 assert!((from..=to).rev().eq((from as u32..=to as u32).filter_map(char::from_u32).rev()));
35
36 assert_eq!(('\u{D7FF}'..='\u{E000}').count(), 2);
37 assert_eq!(('\u{D7FF}'..='\u{E000}').size_hint(), (2, Some(2)));
38 assert_eq!(('\u{D7FF}'..'\u{E000}').count(), 1);
39 assert_eq!(('\u{D7FF}'..'\u{E000}').size_hint(), (1, Some(1)));
40 }
41
42 #[test]
test_range_exhaustion()43 fn test_range_exhaustion() {
44 let mut r = 10..10;
45 assert!(r.is_empty());
46 assert_eq!(r.next(), None);
47 assert_eq!(r.next_back(), None);
48 assert_eq!(r, 10..10);
49
50 let mut r = 10..12;
51 assert_eq!(r.next(), Some(10));
52 assert_eq!(r.next(), Some(11));
53 assert!(r.is_empty());
54 assert_eq!(r, 12..12);
55 assert_eq!(r.next(), None);
56
57 let mut r = 10..12;
58 assert_eq!(r.next_back(), Some(11));
59 assert_eq!(r.next_back(), Some(10));
60 assert!(r.is_empty());
61 assert_eq!(r, 10..10);
62 assert_eq!(r.next_back(), None);
63
64 let mut r = 100..10;
65 assert!(r.is_empty());
66 assert_eq!(r.next(), None);
67 assert_eq!(r.next_back(), None);
68 assert_eq!(r, 100..10);
69 }
70
71 #[test]
test_range_inclusive_exhaustion()72 fn test_range_inclusive_exhaustion() {
73 let mut r = 10..=10;
74 assert_eq!(r.next(), Some(10));
75 assert!(r.is_empty());
76 assert_eq!(r.next(), None);
77 assert_eq!(r.next(), None);
78
79 assert_eq!(*r.start(), 10);
80 assert_eq!(*r.end(), 10);
81 assert_ne!(r, 10..=10);
82
83 let mut r = 10..=10;
84 assert_eq!(r.next_back(), Some(10));
85 assert!(r.is_empty());
86 assert_eq!(r.next_back(), None);
87
88 assert_eq!(*r.start(), 10);
89 assert_eq!(*r.end(), 10);
90 assert_ne!(r, 10..=10);
91
92 let mut r = 10..=12;
93 assert_eq!(r.next(), Some(10));
94 assert_eq!(r.next(), Some(11));
95 assert_eq!(r.next(), Some(12));
96 assert!(r.is_empty());
97 assert_eq!(r.next(), None);
98
99 let mut r = 10..=12;
100 assert_eq!(r.next_back(), Some(12));
101 assert_eq!(r.next_back(), Some(11));
102 assert_eq!(r.next_back(), Some(10));
103 assert!(r.is_empty());
104 assert_eq!(r.next_back(), None);
105
106 let mut r = 10..=12;
107 assert_eq!(r.nth(2), Some(12));
108 assert!(r.is_empty());
109 assert_eq!(r.next(), None);
110
111 let mut r = 10..=12;
112 assert_eq!(r.nth(5), None);
113 assert!(r.is_empty());
114 assert_eq!(r.next(), None);
115
116 let mut r = 100..=10;
117 assert_eq!(r.next(), None);
118 assert!(r.is_empty());
119 assert_eq!(r.next(), None);
120 assert_eq!(r.next(), None);
121 assert_eq!(r, 100..=10);
122
123 let mut r = 100..=10;
124 assert_eq!(r.next_back(), None);
125 assert!(r.is_empty());
126 assert_eq!(r.next_back(), None);
127 assert_eq!(r.next_back(), None);
128 assert_eq!(r, 100..=10);
129 }
130
131 #[test]
test_range_nth()132 fn test_range_nth() {
133 assert_eq!((10..15).nth(0), Some(10));
134 assert_eq!((10..15).nth(1), Some(11));
135 assert_eq!((10..15).nth(4), Some(14));
136 assert_eq!((10..15).nth(5), None);
137
138 let mut r = 10..20;
139 assert_eq!(r.nth(2), Some(12));
140 assert_eq!(r, 13..20);
141 assert_eq!(r.nth(2), Some(15));
142 assert_eq!(r, 16..20);
143 assert_eq!(r.nth(10), None);
144 assert_eq!(r, 20..20);
145 }
146
147 #[test]
test_range_nth_back()148 fn test_range_nth_back() {
149 assert_eq!((10..15).nth_back(0), Some(14));
150 assert_eq!((10..15).nth_back(1), Some(13));
151 assert_eq!((10..15).nth_back(4), Some(10));
152 assert_eq!((10..15).nth_back(5), None);
153 assert_eq!((-120..80_i8).nth_back(199), Some(-120));
154
155 let mut r = 10..20;
156 assert_eq!(r.nth_back(2), Some(17));
157 assert_eq!(r, 10..17);
158 assert_eq!(r.nth_back(2), Some(14));
159 assert_eq!(r, 10..14);
160 assert_eq!(r.nth_back(10), None);
161 assert_eq!(r, 10..10);
162 }
163
164 #[test]
test_range_from_nth()165 fn test_range_from_nth() {
166 assert_eq!((10..).nth(0), Some(10));
167 assert_eq!((10..).nth(1), Some(11));
168 assert_eq!((10..).nth(4), Some(14));
169
170 let mut r = 10..;
171 assert_eq!(r.nth(2), Some(12));
172 assert_eq!(r, 13..);
173 assert_eq!(r.nth(2), Some(15));
174 assert_eq!(r, 16..);
175 assert_eq!(r.nth(10), Some(26));
176 assert_eq!(r, 27..);
177
178 assert_eq!((0..).size_hint(), (usize::MAX, None));
179 }
180
181 #[test]
test_range_from_take()182 fn test_range_from_take() {
183 let mut it = (0..).take(3);
184 assert_eq!(it.next(), Some(0));
185 assert_eq!(it.next(), Some(1));
186 assert_eq!(it.next(), Some(2));
187 assert_eq!(it.next(), None);
188 is_trusted_len((0..).take(3));
189 assert_eq!((0..).take(3).size_hint(), (3, Some(3)));
190 assert_eq!((0..).take(0).size_hint(), (0, Some(0)));
191 assert_eq!((0..).take(usize::MAX).size_hint(), (usize::MAX, Some(usize::MAX)));
192 }
193
194 #[test]
test_range_from_take_collect()195 fn test_range_from_take_collect() {
196 let v: Vec<_> = (0..).take(3).collect();
197 assert_eq!(v, vec![0, 1, 2]);
198 }
199
200 #[test]
test_range_inclusive_nth()201 fn test_range_inclusive_nth() {
202 assert_eq!((10..=15).nth(0), Some(10));
203 assert_eq!((10..=15).nth(1), Some(11));
204 assert_eq!((10..=15).nth(5), Some(15));
205 assert_eq!((10..=15).nth(6), None);
206
207 let mut exhausted_via_next = 10_u8..=20;
208 while exhausted_via_next.next().is_some() {}
209
210 let mut r = 10_u8..=20;
211 assert_eq!(r.nth(2), Some(12));
212 assert_eq!(r, 13..=20);
213 assert_eq!(r.nth(2), Some(15));
214 assert_eq!(r, 16..=20);
215 assert_eq!(r.is_empty(), false);
216 assert_eq!(ExactSizeIterator::is_empty(&r), false);
217 assert_eq!(r.nth(10), None);
218 assert_eq!(r.is_empty(), true);
219 assert_eq!(r, exhausted_via_next);
220 assert_eq!(ExactSizeIterator::is_empty(&r), true);
221 }
222
223 #[test]
test_range_inclusive_nth_back()224 fn test_range_inclusive_nth_back() {
225 assert_eq!((10..=15).nth_back(0), Some(15));
226 assert_eq!((10..=15).nth_back(1), Some(14));
227 assert_eq!((10..=15).nth_back(5), Some(10));
228 assert_eq!((10..=15).nth_back(6), None);
229 assert_eq!((-120..=80_i8).nth_back(200), Some(-120));
230
231 let mut exhausted_via_next_back = 10_u8..=20;
232 while exhausted_via_next_back.next_back().is_some() {}
233
234 let mut r = 10_u8..=20;
235 assert_eq!(r.nth_back(2), Some(18));
236 assert_eq!(r, 10..=17);
237 assert_eq!(r.nth_back(2), Some(15));
238 assert_eq!(r, 10..=14);
239 assert_eq!(r.is_empty(), false);
240 assert_eq!(ExactSizeIterator::is_empty(&r), false);
241 assert_eq!(r.nth_back(10), None);
242 assert_eq!(r.is_empty(), true);
243 assert_eq!(r, exhausted_via_next_back);
244 assert_eq!(ExactSizeIterator::is_empty(&r), true);
245 }
246
247 #[test]
test_range_len()248 fn test_range_len() {
249 assert_eq!((0..10_u8).len(), 10);
250 assert_eq!((9..10_u8).len(), 1);
251 assert_eq!((10..10_u8).len(), 0);
252 assert_eq!((11..10_u8).len(), 0);
253 assert_eq!((100..10_u8).len(), 0);
254 }
255
256 #[test]
test_range_inclusive_len()257 fn test_range_inclusive_len() {
258 assert_eq!((0..=10_u8).len(), 11);
259 assert_eq!((9..=10_u8).len(), 2);
260 assert_eq!((10..=10_u8).len(), 1);
261 assert_eq!((11..=10_u8).len(), 0);
262 assert_eq!((100..=10_u8).len(), 0);
263 }
264
265 #[test]
test_range_step()266 fn test_range_step() {
267 #![allow(deprecated)]
268
269 assert_eq!((0..20).step_by(5).collect::<Vec<isize>>(), [0, 5, 10, 15]);
270 assert_eq!((1..21).rev().step_by(5).collect::<Vec<isize>>(), [20, 15, 10, 5]);
271 assert_eq!((1..21).rev().step_by(6).collect::<Vec<isize>>(), [20, 14, 8, 2]);
272 assert_eq!((200..255).step_by(50).collect::<Vec<u8>>(), [200, 250]);
273 assert_eq!((200..-5).step_by(1).collect::<Vec<isize>>(), []);
274 assert_eq!((200..200).step_by(1).collect::<Vec<isize>>(), []);
275
276 assert_eq!((0..20).step_by(1).size_hint(), (20, Some(20)));
277 assert_eq!((0..20).step_by(21).size_hint(), (1, Some(1)));
278 assert_eq!((0..20).step_by(5).size_hint(), (4, Some(4)));
279 assert_eq!((1..21).rev().step_by(5).size_hint(), (4, Some(4)));
280 assert_eq!((1..21).rev().step_by(6).size_hint(), (4, Some(4)));
281 assert_eq!((20..-5).step_by(1).size_hint(), (0, Some(0)));
282 assert_eq!((20..20).step_by(1).size_hint(), (0, Some(0)));
283 assert_eq!((i8::MIN..i8::MAX).step_by(-(i8::MIN as i32) as usize).size_hint(), (2, Some(2)));
284 assert_eq!((i16::MIN..i16::MAX).step_by(i16::MAX as usize).size_hint(), (3, Some(3)));
285 assert_eq!((isize::MIN..isize::MAX).step_by(1).size_hint(), (usize::MAX, Some(usize::MAX)));
286 }
287
288 #[test]
test_range_advance_by()289 fn test_range_advance_by() {
290 let mut r = 0..usize::MAX;
291 r.advance_by(0).unwrap();
292 r.advance_back_by(0).unwrap();
293
294 assert_eq!(r.len(), usize::MAX);
295
296 r.advance_by(1).unwrap();
297 r.advance_back_by(1).unwrap();
298
299 assert_eq!((r.start, r.end), (1, usize::MAX - 1));
300
301 assert_eq!(r.advance_by(usize::MAX), Err(usize::MAX - 2));
302
303 let mut r = 0u128..u128::MAX;
304
305 r.advance_by(usize::MAX).unwrap();
306 r.advance_back_by(usize::MAX).unwrap();
307
308 assert_eq!((r.start, r.end), (0u128 + usize::MAX as u128, u128::MAX - usize::MAX as u128));
309 }
310
311 #[test]
test_range_inclusive_step()312 fn test_range_inclusive_step() {
313 assert_eq!((0..=50).step_by(10).collect::<Vec<_>>(), [0, 10, 20, 30, 40, 50]);
314 assert_eq!((0..=5).step_by(1).collect::<Vec<_>>(), [0, 1, 2, 3, 4, 5]);
315 assert_eq!((200..=255u8).step_by(10).collect::<Vec<_>>(), [200, 210, 220, 230, 240, 250]);
316 assert_eq!((250..=255u8).step_by(1).collect::<Vec<_>>(), [250, 251, 252, 253, 254, 255]);
317 }
318
319 #[test]
test_range_last_max()320 fn test_range_last_max() {
321 assert_eq!((0..20).last(), Some(19));
322 assert_eq!((-20..0).last(), Some(-1));
323 assert_eq!((5..5).last(), None);
324
325 assert_eq!((0..20).max(), Some(19));
326 assert_eq!((-20..0).max(), Some(-1));
327 assert_eq!((5..5).max(), None);
328 }
329
330 #[test]
test_range_inclusive_last_max()331 fn test_range_inclusive_last_max() {
332 assert_eq!((0..=20).last(), Some(20));
333 assert_eq!((-20..=0).last(), Some(0));
334 assert_eq!((5..=5).last(), Some(5));
335 let mut r = 10..=10;
336 r.next();
337 assert_eq!(r.last(), None);
338
339 assert_eq!((0..=20).max(), Some(20));
340 assert_eq!((-20..=0).max(), Some(0));
341 assert_eq!((5..=5).max(), Some(5));
342 let mut r = 10..=10;
343 r.next();
344 assert_eq!(r.max(), None);
345 }
346
347 #[test]
test_range_min()348 fn test_range_min() {
349 assert_eq!((0..20).min(), Some(0));
350 assert_eq!((-20..0).min(), Some(-20));
351 assert_eq!((5..5).min(), None);
352 }
353
354 #[test]
test_range_inclusive_min()355 fn test_range_inclusive_min() {
356 assert_eq!((0..=20).min(), Some(0));
357 assert_eq!((-20..=0).min(), Some(-20));
358 assert_eq!((5..=5).min(), Some(5));
359 let mut r = 10..=10;
360 r.next();
361 assert_eq!(r.min(), None);
362 }
363
364 #[test]
test_range_inclusive_folds()365 fn test_range_inclusive_folds() {
366 assert_eq!((1..=10).sum::<i32>(), 55);
367 assert_eq!((1..=10).rev().sum::<i32>(), 55);
368
369 let mut it = 44..=50;
370 assert_eq!(it.try_fold(0, i8::checked_add), None);
371 assert_eq!(it, 47..=50);
372 assert_eq!(it.try_fold(0, i8::checked_add), None);
373 assert_eq!(it, 50..=50);
374 assert_eq!(it.try_fold(0, i8::checked_add), Some(50));
375 assert!(it.is_empty());
376 assert_eq!(it.try_fold(0, i8::checked_add), Some(0));
377 assert!(it.is_empty());
378
379 let mut it = 40..=47;
380 assert_eq!(it.try_rfold(0, i8::checked_add), None);
381 assert_eq!(it, 40..=44);
382 assert_eq!(it.try_rfold(0, i8::checked_add), None);
383 assert_eq!(it, 40..=41);
384 assert_eq!(it.try_rfold(0, i8::checked_add), Some(81));
385 assert!(it.is_empty());
386 assert_eq!(it.try_rfold(0, i8::checked_add), Some(0));
387 assert!(it.is_empty());
388
389 let mut it = 10..=20;
390 assert_eq!(it.try_fold(0, |a, b| Some(a + b)), Some(165));
391 assert!(it.is_empty());
392 assert_eq!(it.try_fold(0, |a, b| Some(a + b)), Some(0));
393 assert!(it.is_empty());
394
395 let mut it = 10..=20;
396 assert_eq!(it.try_rfold(0, |a, b| Some(a + b)), Some(165));
397 assert!(it.is_empty());
398 assert_eq!(it.try_rfold(0, |a, b| Some(a + b)), Some(0));
399 assert!(it.is_empty());
400 }
401
402 #[test]
test_range_size_hint()403 fn test_range_size_hint() {
404 assert_eq!((0..0usize).size_hint(), (0, Some(0)));
405 assert_eq!((0..100usize).size_hint(), (100, Some(100)));
406 assert_eq!((0..usize::MAX).size_hint(), (usize::MAX, Some(usize::MAX)));
407
408 let umax = u128::try_from(usize::MAX).unwrap();
409 assert_eq!((0..0u128).size_hint(), (0, Some(0)));
410 assert_eq!((0..100u128).size_hint(), (100, Some(100)));
411 assert_eq!((0..umax).size_hint(), (usize::MAX, Some(usize::MAX)));
412 assert_eq!((0..umax + 1).size_hint(), (usize::MAX, None));
413
414 assert_eq!((0..0isize).size_hint(), (0, Some(0)));
415 assert_eq!((-100..100isize).size_hint(), (200, Some(200)));
416 assert_eq!((isize::MIN..isize::MAX).size_hint(), (usize::MAX, Some(usize::MAX)));
417
418 let imin = i128::try_from(isize::MIN).unwrap();
419 let imax = i128::try_from(isize::MAX).unwrap();
420 assert_eq!((0..0i128).size_hint(), (0, Some(0)));
421 assert_eq!((-100..100i128).size_hint(), (200, Some(200)));
422 assert_eq!((imin..imax).size_hint(), (usize::MAX, Some(usize::MAX)));
423 assert_eq!((imin..imax + 1).size_hint(), (usize::MAX, None));
424 }
425
426 #[test]
test_range_inclusive_size_hint()427 fn test_range_inclusive_size_hint() {
428 assert_eq!((1..=0usize).size_hint(), (0, Some(0)));
429 assert_eq!((0..=0usize).size_hint(), (1, Some(1)));
430 assert_eq!((0..=100usize).size_hint(), (101, Some(101)));
431 assert_eq!((0..=usize::MAX - 1).size_hint(), (usize::MAX, Some(usize::MAX)));
432 assert_eq!((0..=usize::MAX).size_hint(), (usize::MAX, None));
433
434 let umax = u128::try_from(usize::MAX).unwrap();
435 assert_eq!((1..=0u128).size_hint(), (0, Some(0)));
436 assert_eq!((0..=0u128).size_hint(), (1, Some(1)));
437 assert_eq!((0..=100u128).size_hint(), (101, Some(101)));
438 assert_eq!((0..=umax - 1).size_hint(), (usize::MAX, Some(usize::MAX)));
439 assert_eq!((0..=umax).size_hint(), (usize::MAX, None));
440 assert_eq!((0..=umax + 1).size_hint(), (usize::MAX, None));
441
442 assert_eq!((0..=-1isize).size_hint(), (0, Some(0)));
443 assert_eq!((0..=0isize).size_hint(), (1, Some(1)));
444 assert_eq!((-100..=100isize).size_hint(), (201, Some(201)));
445 assert_eq!((isize::MIN..=isize::MAX - 1).size_hint(), (usize::MAX, Some(usize::MAX)));
446 assert_eq!((isize::MIN..=isize::MAX).size_hint(), (usize::MAX, None));
447
448 let imin = i128::try_from(isize::MIN).unwrap();
449 let imax = i128::try_from(isize::MAX).unwrap();
450 assert_eq!((0..=-1i128).size_hint(), (0, Some(0)));
451 assert_eq!((0..=0i128).size_hint(), (1, Some(1)));
452 assert_eq!((-100..=100i128).size_hint(), (201, Some(201)));
453 assert_eq!((imin..=imax - 1).size_hint(), (usize::MAX, Some(usize::MAX)));
454 assert_eq!((imin..=imax).size_hint(), (usize::MAX, None));
455 assert_eq!((imin..=imax + 1).size_hint(), (usize::MAX, None));
456 }
457
458 #[test]
test_double_ended_range()459 fn test_double_ended_range() {
460 assert_eq!((11..14).rev().collect::<Vec<_>>(), [13, 12, 11]);
461 for _ in (10..0).rev() {
462 panic!("unreachable");
463 }
464
465 assert_eq!((11..14).rev().collect::<Vec<_>>(), [13, 12, 11]);
466 for _ in (10..0).rev() {
467 panic!("unreachable");
468 }
469 }
470