1 files changed, 494 insertions, 0 deletions
diff --git a/library/alloc/src/sync/tests.rs b/library/alloc/src/sync/tests.rs
new file mode 100644
index 00000000000..6f08cd7f123
--- /dev/null
+++ b/library/alloc/src/sync/tests.rs
@@ -0,0 +1,494 @@
+use super::*;
+
+use std::boxed::Box;
+use std::clone::Clone;
+use std::convert::{From, TryInto};
+use std::mem::drop;
+use std::ops::Drop;
+use std::option::Option::{self, None, Some};
+use std::sync::atomic::{
+    self,
+    Ordering::{Acquire, SeqCst},
+};
+use std::sync::mpsc::channel;
+use std::sync::Mutex;
+use std::thread;
+
+use crate::vec::Vec;
+
+struct Canary(*mut atomic::AtomicUsize);
+
+impl Drop for Canary {
+    fn drop(&mut self) {
+        unsafe {
+            match *self {
+                Canary(c) => {
+                    (*c).fetch_add(1, SeqCst);
+                }
+            }
+        }
+    }
+}
+
+#[test]
+#[cfg_attr(target_os = "emscripten", ignore)]
+fn manually_share_arc() {
+    let v = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+    let arc_v = Arc::new(v);
+
+    let (tx, rx) = channel();
+
+    let _t = thread::spawn(move || {
+        let arc_v: Arc<Vec<i32>> = rx.recv().unwrap();
+        assert_eq!((*arc_v)[3], 4);
+    });
+
+    tx.send(arc_v.clone()).unwrap();
+
+    assert_eq!((*arc_v)[2], 3);
+    assert_eq!((*arc_v)[4], 5);
+}
+
+#[test]
+fn test_arc_get_mut() {
+    let mut x = Arc::new(3);
+    *Arc::get_mut(&mut x).unwrap() = 4;
+    assert_eq!(*x, 4);
+    let y = x.clone();
+    assert!(Arc::get_mut(&mut x).is_none());
+    drop(y);
+    assert!(Arc::get_mut(&mut x).is_some());
+    let _w = Arc::downgrade(&x);
+    assert!(Arc::get_mut(&mut x).is_none());
+}
+
+#[test]
+fn weak_counts() {
+    assert_eq!(Weak::weak_count(&Weak::<u64>::new()), 0);
+    assert_eq!(Weak::strong_count(&Weak::<u64>::new()), 0);
+
+    let a = Arc::new(0);
+    let w = Arc::downgrade(&a);
+    assert_eq!(Weak::strong_count(&w), 1);
+    assert_eq!(Weak::weak_count(&w), 1);
+    let w2 = w.clone();
+    assert_eq!(Weak::strong_count(&w), 1);
+    assert_eq!(Weak::weak_count(&w), 2);
+    assert_eq!(Weak::strong_count(&w2), 1);
+    assert_eq!(Weak::weak_count(&w2), 2);
+    drop(w);
+    assert_eq!(Weak::strong_count(&w2), 1);
+    assert_eq!(Weak::weak_count(&w2), 1);
+    let a2 = a.clone();
+    assert_eq!(Weak::strong_count(&w2), 2);
+    assert_eq!(Weak::weak_count(&w2), 1);
+    drop(a2);
+    drop(a);
+    assert_eq!(Weak::strong_count(&w2), 0);
+    assert_eq!(Weak::weak_count(&w2), 0);
+    drop(w2);
+}
+
+#[test]
+fn try_unwrap() {
+    let x = Arc::new(3);
+    assert_eq!(Arc::try_unwrap(x), Ok(3));
+    let x = Arc::new(4);
+    let _y = x.clone();
+    assert_eq!(Arc::try_unwrap(x), Err(Arc::new(4)));
+    let x = Arc::new(5);
+    let _w = Arc::downgrade(&x);
+    assert_eq!(Arc::try_unwrap(x), Ok(5));
+}
+
+#[test]
+fn into_from_raw() {
+    let x = Arc::new(box "hello");
+    let y = x.clone();
+
+    let x_ptr = Arc::into_raw(x);
+    drop(y);
+    unsafe {
+        assert_eq!(**x_ptr, "hello");
+
+        let x = Arc::from_raw(x_ptr);
+        assert_eq!(**x, "hello");
+
+        assert_eq!(Arc::try_unwrap(x).map(|x| *x), Ok("hello"));
+    }
+}
+
+#[test]
+fn test_into_from_raw_unsized() {
+    use std::fmt::Display;
+    use std::string::ToString;
+
+    let arc: Arc<str> = Arc::from("foo");
+
+    let ptr = Arc::into_raw(arc.clone());
+    let arc2 = unsafe { Arc::from_raw(ptr) };
+
+    assert_eq!(unsafe { &*ptr }, "foo");
+    assert_eq!(arc, arc2);
+
+    let arc: Arc<dyn Display> = Arc::new(123);
+
+    let ptr = Arc::into_raw(arc.clone());
+    let arc2 = unsafe { Arc::from_raw(ptr) };
+
+    assert_eq!(unsafe { &*ptr }.to_string(), "123");
+    assert_eq!(arc2.to_string(), "123");
+}
+
+#[test]
+fn test_cowarc_clone_make_mut() {
+    let mut cow0 = Arc::new(75);
+    let mut cow1 = cow0.clone();
+    let mut cow2 = cow1.clone();
+
+    assert!(75 == *Arc::make_mut(&mut cow0));
+    assert!(75 == *Arc::make_mut(&mut cow1));
+    assert!(75 == *Arc::make_mut(&mut cow2));
+
+    *Arc::make_mut(&mut cow0) += 1;
+    *Arc::make_mut(&mut cow1) += 2;
+    *Arc::make_mut(&mut cow2) += 3;
+
+    assert!(76 == *cow0);
+    assert!(77 == *cow1);
+    assert!(78 == *cow2);
+
+    // none should point to the same backing memory
+    assert!(*cow0 != *cow1);
+    assert!(*cow0 != *cow2);
+    assert!(*cow1 != *cow2);
+}
+
+#[test]
+fn test_cowarc_clone_unique2() {
+    let mut cow0 = Arc::new(75);
+    let cow1 = cow0.clone();
+    let cow2 = cow1.clone();
+
+    assert!(75 == *cow0);
+    assert!(75 == *cow1);
+    assert!(75 == *cow2);
+
+    *Arc::make_mut(&mut cow0) += 1;
+    assert!(76 == *cow0);
+    assert!(75 == *cow1);
+    assert!(75 == *cow2);
+
+    // cow1 and cow2 should share the same contents
+    // cow0 should have a unique reference
+    assert!(*cow0 != *cow1);
+    assert!(*cow0 != *cow2);
+    assert!(*cow1 == *cow2);
+}
+
+#[test]
+fn test_cowarc_clone_weak() {
+    let mut cow0 = Arc::new(75);
+    let cow1_weak = Arc::downgrade(&cow0);
+
+    assert!(75 == *cow0);
+    assert!(75 == *cow1_weak.upgrade().unwrap());
+
+    *Arc::make_mut(&mut cow0) += 1;
+
+    assert!(76 == *cow0);
+    assert!(cow1_weak.upgrade().is_none());
+}
+
+#[test]
+fn test_live() {
+    let x = Arc::new(5);
+    let y = Arc::downgrade(&x);
+    assert!(y.upgrade().is_some());
+}
+
+#[test]
+fn test_dead() {
+    let x = Arc::new(5);
+    let y = Arc::downgrade(&x);
+    drop(x);
+    assert!(y.upgrade().is_none());
+}
+
+#[test]
+fn weak_self_cyclic() {
+    struct Cycle {
+        x: Mutex<Option<Weak<Cycle>>>,
+    }
+
+    let a = Arc::new(Cycle { x: Mutex::new(None) });
+    let b = Arc::downgrade(&a.clone());
+    *a.x.lock().unwrap() = Some(b);
+
+    // hopefully we don't double-free (or leak)...
+}
+
+#[test]
+fn drop_arc() {
+    let mut canary = atomic::AtomicUsize::new(0);
+    let x = Arc::new(Canary(&mut canary as *mut atomic::AtomicUsize));
+    drop(x);
+    assert!(canary.load(Acquire) == 1);
+}
+
+#[test]
+fn drop_arc_weak() {
+    let mut canary = atomic::AtomicUsize::new(0);
+    let arc = Arc::new(Canary(&mut canary as *mut atomic::AtomicUsize));
+    let arc_weak = Arc::downgrade(&arc);
+    assert!(canary.load(Acquire) == 0);
+    drop(arc);
+    assert!(canary.load(Acquire) == 1);
+    drop(arc_weak);
+}
+
+#[test]
+fn test_strong_count() {
+    let a = Arc::new(0);
+    assert!(Arc::strong_count(&a) == 1);
+    let w = Arc::downgrade(&a);
+    assert!(Arc::strong_count(&a) == 1);
+    let b = w.upgrade().expect("");
+    assert!(Arc::strong_count(&b) == 2);
+    assert!(Arc::strong_count(&a) == 2);
+    drop(w);
+    drop(a);
+    assert!(Arc::strong_count(&b) == 1);
+    let c = b.clone();
+    assert!(Arc::strong_count(&b) == 2);
+    assert!(Arc::strong_count(&c) == 2);
+}
+
+#[test]
+fn test_weak_count() {
+    let a = Arc::new(0);
+    assert!(Arc::strong_count(&a) == 1);
+    assert!(Arc::weak_count(&a) == 0);
+    let w = Arc::downgrade(&a);
+    assert!(Arc::strong_count(&a) == 1);
+    assert!(Arc::weak_count(&a) == 1);
+    let x = w.clone();
+    assert!(Arc::weak_count(&a) == 2);
+    drop(w);
+    drop(x);
+    assert!(Arc::strong_count(&a) == 1);
+    assert!(Arc::weak_count(&a) == 0);
+    let c = a.clone();
+    assert!(Arc::strong_count(&a) == 2);
+    assert!(Arc::weak_count(&a) == 0);
+    let d = Arc::downgrade(&c);
+    assert!(Arc::weak_count(&c) == 1);
+    assert!(Arc::strong_count(&c) == 2);
+
+    drop(a);
+    drop(c);
+    drop(d);
+}
+
+#[test]
+fn show_arc() {
+    let a = Arc::new(5);
+    assert_eq!(format!("{:?}", a), "5");
+}
+
+// Make sure deriving works with Arc<T>
+#[derive(Eq, Ord, PartialEq, PartialOrd, Clone, Debug, Default)]
+struct Foo {
+    inner: Arc<i32>,
+}
+
+#[test]
+fn test_unsized() {
+    let x: Arc<[i32]> = Arc::new([1, 2, 3]);
+    assert_eq!(format!("{:?}", x), "[1, 2, 3]");
+    let y = Arc::downgrade(&x.clone());
+    drop(x);
+    assert!(y.upgrade().is_none());
+}
+
+#[test]
+fn test_from_owned() {
+    let foo = 123;
+    let foo_arc = Arc::from(foo);
+    assert!(123 == *foo_arc);
+}
+
+#[test]
+fn test_new_weak() {
+    let foo: Weak<usize> = Weak::new();
+    assert!(foo.upgrade().is_none());
+}
+
+#[test]
+fn test_ptr_eq() {
+    let five = Arc::new(5);
+    let same_five = five.clone();
+    let other_five = Arc::new(5);
+
+    assert!(Arc::ptr_eq(&five, &same_five));
+    assert!(!Arc::ptr_eq(&five, &other_five));
+}
+
+#[test]
+#[cfg_attr(target_os = "emscripten", ignore)]
+fn test_weak_count_locked() {
+    let mut a = Arc::new(atomic::AtomicBool::new(false));
+    let a2 = a.clone();
+    let t = thread::spawn(move || {
+        // Miri is too slow
+        let count = if cfg!(miri) { 1000 } else { 1000000 };
+        for _i in 0..count {
+            Arc::get_mut(&mut a);
+        }
+        a.store(true, SeqCst);
+    });
+
+    while !a2.load(SeqCst) {
+        let n = Arc::weak_count(&a2);
+        assert!(n < 2, "bad weak count: {}", n);
+        #[cfg(miri)] // Miri's scheduler does not guarantee liveness, and thus needs this hint.
+        atomic::spin_loop_hint();
+    }
+    t.join().unwrap();
+}
+
+#[test]
+fn test_from_str() {
+    let r: Arc<str> = Arc::from("foo");
+
+    assert_eq!(&r[..], "foo");
+}
+
+#[test]
+fn test_copy_from_slice() {
+    let s: &[u32] = &[1, 2, 3];
+    let r: Arc<[u32]> = Arc::from(s);
+
+    assert_eq!(&r[..], [1, 2, 3]);
+}
+
+#[test]
+fn test_clone_from_slice() {
+    #[derive(Clone, Debug, Eq, PartialEq)]
+    struct X(u32);
+
+    let s: &[X] = &[X(1), X(2), X(3)];
+    let r: Arc<[X]> = Arc::from(s);
+
+    assert_eq!(&r[..], s);
+}
+
+#[test]
+#[should_panic]
+fn test_clone_from_slice_panic() {
+    use std::string::{String, ToString};
+
+    struct Fail(u32, String);
+
+    impl Clone for Fail {
+        fn clone(&self) -> Fail {
+            if self.0 == 2 {
+                panic!();
+            }
+            Fail(self.0, self.1.clone())
+        }
+    }
+
+    let s: &[Fail] =
+        &[Fail(0, "foo".to_string()), Fail(1, "bar".to_string()), Fail(2, "baz".to_string())];
+
+    // Should panic, but not cause memory corruption
+    let _r: Arc<[Fail]> = Arc::from(s);
+}
+
+#[test]
+fn test_from_box() {
+    let b: Box<u32> = box 123;
+    let r: Arc<u32> = Arc::from(b);
+
+    assert_eq!(*r, 123);
+}
+
+#[test]
+fn test_from_box_str() {
+    use std::string::String;
+
+    let s = String::from("foo").into_boxed_str();
+    let r: Arc<str> = Arc::from(s);
+
+    assert_eq!(&r[..], "foo");
+}
+
+#[test]
+fn test_from_box_slice() {
+    let s = vec![1, 2, 3].into_boxed_slice();
+    let r: Arc<[u32]> = Arc::from(s);
+
+    assert_eq!(&r[..], [1, 2, 3]);
+}
+
+#[test]
+fn test_from_box_trait() {
+    use std::fmt::Display;
+    use std::string::ToString;
+
+    let b: Box<dyn Display> = box 123;
+    let r: Arc<dyn Display> = Arc::from(b);
+
+    assert_eq!(r.to_string(), "123");
+}
+
+#[test]
+fn test_from_box_trait_zero_sized() {
+    use std::fmt::Debug;
+
+    let b: Box<dyn Debug> = box ();
+    let r: Arc<dyn Debug> = Arc::from(b);
+
+    assert_eq!(format!("{:?}", r), "()");
+}
+
+#[test]
+fn test_from_vec() {
+    let v = vec![1, 2, 3];
+    let r: Arc<[u32]> = Arc::from(v);
+
+    assert_eq!(&r[..], [1, 2, 3]);
+}
+
+#[test]
+fn test_downcast() {
+    use std::any::Any;
+
+    let r1: Arc<dyn Any + Send + Sync> = Arc::new(i32::MAX);
+    let r2: Arc<dyn Any + Send + Sync> = Arc::new("abc");
+
+    assert!(r1.clone().downcast::<u32>().is_err());
+
+    let r1i32 = r1.downcast::<i32>();
+    assert!(r1i32.is_ok());
+    assert_eq!(r1i32.unwrap(), Arc::new(i32::MAX));
+
+    assert!(r2.clone().downcast::<i32>().is_err());
+
+    let r2str = r2.downcast::<&'static str>();
+    assert!(r2str.is_ok());
+    assert_eq!(r2str.unwrap(), Arc::new("abc"));
+}
+
+#[test]
+fn test_array_from_slice() {
+    let v = vec![1, 2, 3];
+    let r: Arc<[u32]> = Arc::from(v);
+
+    let a: Result<Arc<[u32; 3]>, _> = r.clone().try_into();
+    assert!(a.is_ok());
+
+    let a: Result<Arc<[u32; 2]>, _> = r.clone().try_into();
+    assert!(a.is_err());
+}