4 files changed, 45 insertions, 12 deletions
diff --git a/src/liballoc/tests/boxed.rs b/src/liballoc/tests/boxed.rs
new file mode 100644
index 00000000000..bc3d53bf30d
--- /dev/null
+++ b/src/liballoc/tests/boxed.rs
@@ -0,0 +1,18 @@
+use std::ptr::NonNull;
+use std::mem::MaybeUninit;
+
+#[test]
+fn unitialized_zero_size_box() {
+    assert_eq!(
+        &*Box::<()>::new_uninit() as *const _,
+        NonNull::<MaybeUninit<()>>::dangling().as_ptr(),
+    );
+    assert_eq!(
+        Box::<[()]>::new_uninit_slice(4).as_ptr(),
+        NonNull::<MaybeUninit<()>>::dangling().as_ptr(),
+    );
+    assert_eq!(
+        Box::<[String]>::new_uninit_slice(0).as_ptr(),
+        NonNull::<MaybeUninit<String>>::dangling().as_ptr(),
+    );
+}
diff --git a/src/liballoc/tests/btree/set.rs b/src/liballoc/tests/btree/set.rs
index 5c611fd21d2..e4883abc8b5 100644
--- a/src/liballoc/tests/btree/set.rs
+++ b/src/liballoc/tests/btree/set.rs
@@ -222,6 +222,18 @@ fn test_symmetric_difference() {
 }
 
 #[test]
+fn test_symmetric_difference_size_hint() {
+    let x: BTreeSet<i32> = [2, 4].iter().copied().collect();
+    let y: BTreeSet<i32> = [1, 2, 3].iter().copied().collect();
+    let mut iter = x.symmetric_difference(&y);
+    assert_eq!(iter.size_hint(), (0, Some(5)));
+    assert_eq!(iter.next(), Some(&1));
+    assert_eq!(iter.size_hint(), (0, Some(4)));
+    assert_eq!(iter.next(), Some(&3));
+    assert_eq!(iter.size_hint(), (0, Some(1)));
+}
+
+#[test]
 fn test_union() {
     fn check_union(a: &[i32], b: &[i32], expected: &[i32]) {
         check(a, b, expected, |x, y, f| x.union(y).all(f))
@@ -236,6 +248,18 @@ fn test_union() {
 }
 
 #[test]
+fn test_union_size_hint() {
+    let x: BTreeSet<i32> = [2, 4].iter().copied().collect();
+    let y: BTreeSet<i32> = [1, 2, 3].iter().copied().collect();
+    let mut iter = x.union(&y);
+    assert_eq!(iter.size_hint(), (3, Some(5)));
+    assert_eq!(iter.next(), Some(&1));
+    assert_eq!(iter.size_hint(), (2, Some(4)));
+    assert_eq!(iter.next(), Some(&2));
+    assert_eq!(iter.size_hint(), (1, Some(2)));
+}
+
+#[test]
 // Only tests the simple function definition with respect to intersection
 fn test_is_disjoint() {
     let one = [1].iter().collect::<BTreeSet<_>>();
@@ -244,7 +268,7 @@ fn test_is_disjoint() {
 }
 
 #[test]
-// Also tests the trivial function definition of is_superset
+// Also implicitly tests the trivial function definition of is_superset
 fn test_is_subset() {
     fn is_subset(a: &[i32], b: &[i32]) -> bool {
         let set_a = a.iter().collect::<BTreeSet<_>>();
diff --git a/src/liballoc/tests/lib.rs b/src/liballoc/tests/lib.rs
index 5723a30c0f3..676874c8b27 100644
--- a/src/liballoc/tests/lib.rs
+++ b/src/liballoc/tests/lib.rs
@@ -2,9 +2,9 @@
 #![feature(box_syntax)]
 #![feature(drain_filter)]
 #![feature(exact_size_is_empty)]
+#![feature(new_uninit)]
 #![feature(option_flattening)]
 #![feature(pattern)]
-#![feature(repeat_generic_slice)]
 #![feature(trusted_len)]
 #![feature(try_reserve)]
 #![feature(unboxed_closures)]
@@ -15,6 +15,7 @@ use std::collections::hash_map::DefaultHasher;
 
 mod arc;
 mod binary_heap;
+mod boxed;
 mod btree;
 mod cow_str;
 mod fmt;
diff --git a/src/liballoc/tests/str.rs.rej b/src/liballoc/tests/str.rs.rej
deleted file mode 100644
index abcba0c2e84..00000000000
--- a/src/liballoc/tests/str.rs.rej
+++ /dev/null
@@ -1,10 +0,0 @@
-diff a/src/liballoc/tests/str.rs b/src/liballoc/tests/str.rs	(rejected hunks)
-@@ -483,7 +483,7 @@ mod slice_index {
-     }
- 
-     #[test]
--    #[cfg(not(target_arch = "asmjs"))] // hits an OOM
-+    #[cfg(not(target_arch = "js"))] // hits an OOM
-     #[cfg(not(miri))] // Miri is too slow
-     fn simple_big() {
-         fn a_million_letter_x() -> String {