Move libXtest into libX/tests

This change moves:

1. `libcoretest` into `libcore/tests`
2. `libcollectionstest` into `libcollections/tests`

This is a follow-up to #39561.

1 files changed, 291 insertions, 0 deletions

diff --git a/src/libcore/tests/slice.rs b/src/libcore/tests/slice.rs
new file mode 100644
index 00000000000..ec38345030f
--- /dev/null
+++ b/src/libcore/tests/slice.rs
@@ -0,0 +1,291 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use core::cmp::Ordering::{Equal, Greater, Less};
+use core::slice::heapsort;
+use core::result::Result::{Ok, Err};
+use rand::{Rng, XorShiftRng};
+
+#[test]
+fn test_binary_search() {
+    let b = [1, 2, 4, 6, 8, 9];
+    assert!(b.binary_search_by(|v| v.cmp(&6)) == Ok(3));
+    assert!(b.binary_search_by(|v| v.cmp(&5)) == Err(3));
+    let b = [1, 2, 4, 6, 7, 8, 9];
+    assert!(b.binary_search_by(|v| v.cmp(&6)) == Ok(3));
+    assert!(b.binary_search_by(|v| v.cmp(&5)) == Err(3));
+    let b = [1, 2, 4, 6, 8, 9];
+    assert!(b.binary_search_by(|v| v.cmp(&8)) == Ok(4));
+    assert!(b.binary_search_by(|v| v.cmp(&7)) == Err(4));
+    let b = [1, 2, 4, 6, 7, 8, 9];
+    assert!(b.binary_search_by(|v| v.cmp(&8)) == Ok(5));
+    let b = [1, 2, 4, 5, 6, 8, 9];
+    assert!(b.binary_search_by(|v| v.cmp(&7)) == Err(5));
+    assert!(b.binary_search_by(|v| v.cmp(&0)) == Err(0));
+    let b = [1, 2, 4, 5, 6, 8];
+    assert!(b.binary_search_by(|v| v.cmp(&9)) == Err(6));
+}
+
+#[test]
+fn test_iterator_nth() {
+    let v: &[_] = &[0, 1, 2, 3, 4];
+    for i in 0..v.len() {
+        assert_eq!(v.iter().nth(i).unwrap(), &v[i]);
+    }
+    assert_eq!(v.iter().nth(v.len()), None);
+
+    let mut iter = v.iter();
+    assert_eq!(iter.nth(2).unwrap(), &v[2]);
+    assert_eq!(iter.nth(1).unwrap(), &v[4]);
+}
+
+#[test]
+fn test_iterator_last() {
+    let v: &[_] = &[0, 1, 2, 3, 4];
+    assert_eq!(v.iter().last().unwrap(), &4);
+    assert_eq!(v[..1].iter().last().unwrap(), &0);
+}
+
+#[test]
+fn test_iterator_count() {
+    let v: &[_] = &[0, 1, 2, 3, 4];
+    assert_eq!(v.iter().count(), 5);
+
+    let mut iter2 = v.iter();
+    iter2.next();
+    iter2.next();
+    assert_eq!(iter2.count(), 3);
+}
+
+#[test]
+fn test_chunks_count() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5];
+    let c = v.chunks(3);
+    assert_eq!(c.count(), 2);
+
+    let v2: &[i32] = &[0, 1, 2, 3, 4];
+    let c2 = v2.chunks(2);
+    assert_eq!(c2.count(), 3);
+
+    let v3: &[i32] = &[];
+    let c3 = v3.chunks(2);
+    assert_eq!(c3.count(), 0);
+}
+
+#[test]
+fn test_chunks_nth() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5];
+    let mut c = v.chunks(2);
+    assert_eq!(c.nth(1).unwrap()[1], 3);
+    assert_eq!(c.next().unwrap()[0], 4);
+
+    let v2: &[i32] = &[0, 1, 2, 3, 4];
+    let mut c2 = v2.chunks(3);
+    assert_eq!(c2.nth(1).unwrap()[1], 4);
+    assert_eq!(c2.next(), None);
+}
+
+#[test]
+fn test_chunks_last() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5];
+    let c = v.chunks(2);
+    assert_eq!(c.last().unwrap()[1], 5);
+
+    let v2: &[i32] = &[0, 1, 2, 3, 4];
+    let c2 = v2.chunks(2);
+    assert_eq!(c2.last().unwrap()[0], 4);
+}
+
+#[test]
+fn test_chunks_mut_count() {
+    let mut v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5];
+    let c = v.chunks_mut(3);
+    assert_eq!(c.count(), 2);
+
+    let mut v2: &mut [i32] = &mut [0, 1, 2, 3, 4];
+    let c2 = v2.chunks_mut(2);
+    assert_eq!(c2.count(), 3);
+
+    let mut v3: &mut [i32] = &mut [];
+    let c3 = v3.chunks_mut(2);
+    assert_eq!(c3.count(), 0);
+}
+
+#[test]
+fn test_chunks_mut_nth() {
+    let mut v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5];
+    let mut c = v.chunks_mut(2);
+    assert_eq!(c.nth(1).unwrap()[1], 3);
+    assert_eq!(c.next().unwrap()[0], 4);
+
+    let mut v2: &mut [i32] = &mut [0, 1, 2, 3, 4];
+    let mut c2 = v2.chunks_mut(3);
+    assert_eq!(c2.nth(1).unwrap()[1], 4);
+    assert_eq!(c2.next(), None);
+}
+
+#[test]
+fn test_chunks_mut_last() {
+    let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5];
+    let c = v.chunks_mut(2);
+    assert_eq!(c.last().unwrap()[1], 5);
+
+    let v2: &mut [i32] = &mut [0, 1, 2, 3, 4];
+    let c2 = v2.chunks_mut(2);
+    assert_eq!(c2.last().unwrap()[0], 4);
+}
+
+#[test]
+fn test_windows_count() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5];
+    let c = v.windows(3);
+    assert_eq!(c.count(), 4);
+
+    let v2: &[i32] = &[0, 1, 2, 3, 4];
+    let c2 = v2.windows(6);
+    assert_eq!(c2.count(), 0);
+
+    let v3: &[i32] = &[];
+    let c3 = v3.windows(2);
+    assert_eq!(c3.count(), 0);
+}
+
+#[test]
+fn test_windows_nth() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5];
+    let mut c = v.windows(2);
+    assert_eq!(c.nth(2).unwrap()[1], 3);
+    assert_eq!(c.next().unwrap()[0], 3);
+
+    let v2: &[i32] = &[0, 1, 2, 3, 4];
+    let mut c2 = v2.windows(4);
+    assert_eq!(c2.nth(1).unwrap()[1], 2);
+    assert_eq!(c2.next(), None);
+}
+
+#[test]
+fn test_windows_last() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5];
+    let c = v.windows(2);
+    assert_eq!(c.last().unwrap()[1], 5);
+
+    let v2: &[i32] = &[0, 1, 2, 3, 4];
+    let c2 = v2.windows(2);
+    assert_eq!(c2.last().unwrap()[0], 3);
+}
+
+#[test]
+fn get_range() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5];
+    assert_eq!(v.get(..), Some(&[0, 1, 2, 3, 4, 5][..]));
+    assert_eq!(v.get(..2), Some(&[0, 1][..]));
+    assert_eq!(v.get(2..), Some(&[2, 3, 4, 5][..]));
+    assert_eq!(v.get(1..4), Some(&[1, 2, 3][..]));
+    assert_eq!(v.get(7..), None);
+    assert_eq!(v.get(7..10), None);
+}
+
+#[test]
+fn get_mut_range() {
+    let mut v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5];
+    assert_eq!(v.get_mut(..), Some(&mut [0, 1, 2, 3, 4, 5][..]));
+    assert_eq!(v.get_mut(..2), Some(&mut [0, 1][..]));
+    assert_eq!(v.get_mut(2..), Some(&mut [2, 3, 4, 5][..]));
+    assert_eq!(v.get_mut(1..4), Some(&mut [1, 2, 3][..]));
+    assert_eq!(v.get_mut(7..), None);
+    assert_eq!(v.get_mut(7..10), None);
+}
+
+#[test]
+fn get_unchecked_range() {
+    unsafe {
+        let v: &[i32] = &[0, 1, 2, 3, 4, 5];
+        assert_eq!(v.get_unchecked(..), &[0, 1, 2, 3, 4, 5][..]);
+        assert_eq!(v.get_unchecked(..2), &[0, 1][..]);
+        assert_eq!(v.get_unchecked(2..), &[2, 3, 4, 5][..]);
+        assert_eq!(v.get_unchecked(1..4), &[1, 2, 3][..]);
+    }
+}
+
+#[test]
+fn get_unchecked_mut_range() {
+    unsafe {
+        let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5];
+        assert_eq!(v.get_unchecked_mut(..), &mut [0, 1, 2, 3, 4, 5][..]);
+        assert_eq!(v.get_unchecked_mut(..2), &mut [0, 1][..]);
+        assert_eq!(v.get_unchecked_mut(2..), &mut[2, 3, 4, 5][..]);
+        assert_eq!(v.get_unchecked_mut(1..4), &mut [1, 2, 3][..]);
+    }
+}
+
+#[test]
+fn sort_unstable() {
+    let mut v = [0; 600];
+    let mut tmp = [0; 600];
+    let mut rng = XorShiftRng::new_unseeded();
+
+    for len in (2..25).chain(500..510) {
+        let v = &mut v[0..len];
+        let tmp = &mut tmp[0..len];
+
+        for &modulus in &[5, 10, 100, 1000] {
+            for _ in 0..100 {
+                for i in 0..len {
+                    v[i] = rng.gen::<i32>() % modulus;
+                }
+
+                // Sort in default order.
+                tmp.copy_from_slice(v);
+                tmp.sort_unstable();
+                assert!(tmp.windows(2).all(|w| w[0] <= w[1]));
+
+                // Sort in ascending order.
+                tmp.copy_from_slice(v);
+                tmp.sort_unstable_by(|a, b| a.cmp(b));
+                assert!(tmp.windows(2).all(|w| w[0] <= w[1]));
+
+                // Sort in descending order.
+                tmp.copy_from_slice(v);
+                tmp.sort_unstable_by(|a, b| b.cmp(a));
+                assert!(tmp.windows(2).all(|w| w[0] >= w[1]));
+
+                // Test heapsort using `<` operator.
+                tmp.copy_from_slice(v);
+                heapsort(tmp, |a, b| a < b);
+                assert!(tmp.windows(2).all(|w| w[0] <= w[1]));
+
+                // Test heapsort using `>` operator.
+                tmp.copy_from_slice(v);
+                heapsort(tmp, |a, b| a > b);
+                assert!(tmp.windows(2).all(|w| w[0] >= w[1]));
+            }
+        }
+    }
+
+    // Sort using a completely random comparison function.
+    // This will reorder the elements *somehow*, but won't panic.
+    for i in 0..v.len() {
+        v[i] = i as i32;
+    }
+    v.sort_unstable_by(|_, _| *rng.choose(&[Less, Equal, Greater]).unwrap());
+    v.sort_unstable();
+    for i in 0..v.len() {
+        assert_eq!(v[i], i as i32);
+    }
+
+    // Should not panic.
+    [0i32; 0].sort_unstable();
+    [(); 10].sort_unstable();
+    [(); 100].sort_unstable();
+
+    let mut v = [0xDEADBEEFu64];
+    v.sort_unstable();
+    assert!(v == [0xDEADBEEF]);
+}