Merging upstream version 1.68.2+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 34 insertions, 0 deletions

diff --git a/tests/ui/traits/conditional-dispatch.rs b/tests/ui/traits/conditional-dispatch.rs
new file mode 100644
index 000000000..dd882dce6
--- /dev/null
+++ b/tests/ui/traits/conditional-dispatch.rs
@@ -0,0 +1,34 @@
+// run-pass
+// Test that we are able to resolve conditional dispatch.  Here, the
+// blanket impl for T:Copy coexists with an impl for Box<T>, because
+// Box does not impl Copy.
+
+
+trait Get {
+    fn get(&self) -> Self;
+}
+
+trait MyCopy { fn copy(&self) -> Self; }
+impl MyCopy for u16 { fn copy(&self) -> Self { *self } }
+impl MyCopy for u32 { fn copy(&self) -> Self { *self } }
+impl MyCopy for i32 { fn copy(&self) -> Self { *self } }
+impl<T:Copy> MyCopy for Option<T> { fn copy(&self) -> Self { *self } }
+
+impl<T:MyCopy> Get for T {
+    fn get(&self) -> T { self.copy() }
+}
+
+impl Get for Box<i32> {
+    fn get(&self) -> Box<i32> { Box::new(get_it(&**self)) }
+}
+
+fn get_it<T:Get>(t: &T) -> T {
+    (*t).get()
+}
+
+fn main() {
+    assert_eq!(get_it(&1_u32), 1_u32);
+    assert_eq!(get_it(&1_u16), 1_u16);
+    assert_eq!(get_it(&Some(1_u16)), Some(1_u16));
+    assert_eq!(get_it(&Box::new(1)), Box::new(1));
+}