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Diffstat (limited to 'library/core/tests/array.rs')
| -rw-r--r-- | library/core/tests/array.rs | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/library/core/tests/array.rs b/library/core/tests/array.rs new file mode 100644 index 00000000000..4bc44e98fc8 --- /dev/null +++ b/library/core/tests/array.rs @@ -0,0 +1,292 @@ +use core::array::{FixedSizeArray, IntoIter}; +use core::convert::TryFrom; + +#[test] +fn fixed_size_array() { + let mut array = [0; 64]; + let mut zero_sized = [(); 64]; + let mut empty_array = [0; 0]; + let mut empty_zero_sized = [(); 0]; + + assert_eq!(FixedSizeArray::as_slice(&array).len(), 64); + assert_eq!(FixedSizeArray::as_slice(&zero_sized).len(), 64); + assert_eq!(FixedSizeArray::as_slice(&empty_array).len(), 0); + assert_eq!(FixedSizeArray::as_slice(&empty_zero_sized).len(), 0); + + assert_eq!(FixedSizeArray::as_mut_slice(&mut array).len(), 64); + assert_eq!(FixedSizeArray::as_mut_slice(&mut zero_sized).len(), 64); + assert_eq!(FixedSizeArray::as_mut_slice(&mut empty_array).len(), 0); + assert_eq!(FixedSizeArray::as_mut_slice(&mut empty_zero_sized).len(), 0); +} + +#[test] +fn array_try_from() { + macro_rules! test { + ($($N:expr)+) => { + $({ + type Array = [u8; $N]; + let array: Array = [0; $N]; + let slice: &[u8] = &array[..]; + + let result = <&Array>::try_from(slice); + assert_eq!(&array, result.unwrap()); + })+ + } + } + test! { + 0 1 2 3 4 5 6 7 8 9 + 10 11 12 13 14 15 16 17 18 19 + 20 21 22 23 24 25 26 27 28 29 + 30 31 32 + } +} + +#[test] +fn iterator_collect() { + let arr = [0, 1, 2, 5, 9]; + let v: Vec<_> = IntoIter::new(arr.clone()).collect(); + assert_eq!(&arr[..], &v[..]); +} + +#[test] +fn iterator_rev_collect() { + let arr = [0, 1, 2, 5, 9]; + let v: Vec<_> = IntoIter::new(arr.clone()).rev().collect(); + assert_eq!(&v[..], &[9, 5, 2, 1, 0]); +} + +#[test] +fn iterator_nth() { + let v = [0, 1, 2, 3, 4]; + for i in 0..v.len() { + assert_eq!(IntoIter::new(v.clone()).nth(i).unwrap(), v[i]); + } + assert_eq!(IntoIter::new(v.clone()).nth(v.len()), None); + + let mut iter = IntoIter::new(v); + assert_eq!(iter.nth(2).unwrap(), v[2]); + assert_eq!(iter.nth(1).unwrap(), v[4]); +} + +#[test] +fn iterator_last() { + let v = [0, 1, 2, 3, 4]; + assert_eq!(IntoIter::new(v).last().unwrap(), 4); + assert_eq!(IntoIter::new([0]).last().unwrap(), 0); + + let mut it = IntoIter::new([0, 9, 2, 4]); + assert_eq!(it.next_back(), Some(4)); + assert_eq!(it.last(), Some(2)); +} + +#[test] +fn iterator_clone() { + let mut it = IntoIter::new([0, 2, 4, 6, 8]); + assert_eq!(it.next(), Some(0)); + assert_eq!(it.next_back(), Some(8)); + let mut clone = it.clone(); + assert_eq!(it.next_back(), Some(6)); + assert_eq!(clone.next_back(), Some(6)); + assert_eq!(it.next_back(), Some(4)); + assert_eq!(clone.next_back(), Some(4)); + assert_eq!(it.next(), Some(2)); + assert_eq!(clone.next(), Some(2)); +} + +#[test] +fn iterator_fused() { + let mut it = IntoIter::new([0, 9, 2]); + assert_eq!(it.next(), Some(0)); + assert_eq!(it.next(), Some(9)); + assert_eq!(it.next(), Some(2)); + assert_eq!(it.next(), None); + assert_eq!(it.next(), None); + assert_eq!(it.next(), None); + assert_eq!(it.next(), None); + assert_eq!(it.next(), None); +} + +#[test] +fn iterator_len() { + let mut it = IntoIter::new([0, 1, 2, 5, 9]); + assert_eq!(it.size_hint(), (5, Some(5))); + assert_eq!(it.len(), 5); + assert_eq!(it.is_empty(), false); + + assert_eq!(it.next(), Some(0)); + assert_eq!(it.size_hint(), (4, Some(4))); + assert_eq!(it.len(), 4); + assert_eq!(it.is_empty(), false); + + assert_eq!(it.next_back(), Some(9)); + assert_eq!(it.size_hint(), (3, Some(3))); + assert_eq!(it.len(), 3); + assert_eq!(it.is_empty(), false); + + // Empty + let it = IntoIter::new([] as [String; 0]); + assert_eq!(it.size_hint(), (0, Some(0))); + assert_eq!(it.len(), 0); + assert_eq!(it.is_empty(), true); +} + +#[test] +fn iterator_count() { + let v = [0, 1, 2, 3, 4]; + assert_eq!(IntoIter::new(v.clone()).count(), 5); + + let mut iter2 = IntoIter::new(v); + iter2.next(); + iter2.next(); + assert_eq!(iter2.count(), 3); +} + +#[test] +fn iterator_flat_map() { + assert!((0..5).flat_map(|i| IntoIter::new([2 * i, 2 * i + 1])).eq(0..10)); +} + +#[test] +fn iterator_debug() { + let arr = [0, 1, 2, 5, 9]; + assert_eq!(format!("{:?}", IntoIter::new(arr)), "IntoIter([0, 1, 2, 5, 9])",); +} + +#[test] +fn iterator_drops() { + use core::cell::Cell; + + // This test makes sure the correct number of elements are dropped. The `R` + // type is just a reference to a `Cell` that is incremented when an `R` is + // dropped. + + #[derive(Clone)] + struct Foo<'a>(&'a Cell<usize>); + + impl Drop for Foo<'_> { + fn drop(&mut self) { + self.0.set(self.0.get() + 1); + } + } + + fn five(i: &Cell<usize>) -> [Foo<'_>; 5] { + // This is somewhat verbose because `Foo` does not implement `Copy` + // since it implements `Drop`. Consequently, we cannot write + // `[Foo(i); 5]`. + [Foo(i), Foo(i), Foo(i), Foo(i), Foo(i)] + } + + // Simple: drop new iterator. + let i = Cell::new(0); + { + IntoIter::new(five(&i)); + } + assert_eq!(i.get(), 5); + + // Call `next()` once. + let i = Cell::new(0); + { + let mut iter = IntoIter::new(five(&i)); + let _x = iter.next(); + assert_eq!(i.get(), 0); + assert_eq!(iter.count(), 4); + assert_eq!(i.get(), 4); + } + assert_eq!(i.get(), 5); + + // Check `clone` and calling `next`/`next_back`. + let i = Cell::new(0); + { + let mut iter = IntoIter::new(five(&i)); + iter.next(); + assert_eq!(i.get(), 1); + iter.next_back(); + assert_eq!(i.get(), 2); + + let mut clone = iter.clone(); + assert_eq!(i.get(), 2); + + iter.next(); + assert_eq!(i.get(), 3); + + clone.next(); + assert_eq!(i.get(), 4); + + assert_eq!(clone.count(), 2); + assert_eq!(i.get(), 6); + } + assert_eq!(i.get(), 8); + + // Check via `nth`. + let i = Cell::new(0); + { + let mut iter = IntoIter::new(five(&i)); + let _x = iter.nth(2); + assert_eq!(i.get(), 2); + let _y = iter.last(); + assert_eq!(i.get(), 3); + } + assert_eq!(i.get(), 5); + + // Check every element. + let i = Cell::new(0); + for (index, _x) in IntoIter::new(five(&i)).enumerate() { + assert_eq!(i.get(), index); + } + assert_eq!(i.get(), 5); + + let i = Cell::new(0); + for (index, _x) in IntoIter::new(five(&i)).rev().enumerate() { + assert_eq!(i.get(), index); + } + assert_eq!(i.get(), 5); +} + +// This test does not work on targets without panic=unwind support. +// To work around this problem, test is marked is should_panic, so it will +// be automagically skipped on unsuitable targets, such as +// wasm32-unknown-unkown. +// +// It means that we use panic for indicating success. +#[test] +#[should_panic(expected = "test succeeded")] +fn array_default_impl_avoids_leaks_on_panic() { + use core::sync::atomic::{AtomicUsize, Ordering::Relaxed}; + static COUNTER: AtomicUsize = AtomicUsize::new(0); + #[derive(Debug)] + struct Bomb(usize); + + impl Default for Bomb { + fn default() -> Bomb { + if COUNTER.load(Relaxed) == 3 { + panic!("bomb limit exceeded"); + } + + COUNTER.fetch_add(1, Relaxed); + Bomb(COUNTER.load(Relaxed)) + } + } + + impl Drop for Bomb { + fn drop(&mut self) { + COUNTER.fetch_sub(1, Relaxed); + } + } + + let res = std::panic::catch_unwind(|| <[Bomb; 5]>::default()); + let panic_msg = match res { + Ok(_) => unreachable!(), + Err(p) => p.downcast::<&'static str>().unwrap(), + }; + assert_eq!(*panic_msg, "bomb limit exceeded"); + // check that all bombs are successfully dropped + assert_eq!(COUNTER.load(Relaxed), 0); + panic!("test succeeded") +} + +#[test] +fn empty_array_is_always_default() { + struct DoesNotImplDefault; + + let _arr = <[DoesNotImplDefault; 0]>::default(); +} |