make `Sized` coinductive

2 files changed, 42 insertions, 0 deletions

diff --git a/src/test/ui/sized/coinductive-1.rs b/src/test/ui/sized/coinductive-1.rs
new file mode 100644
index 00000000000..7bcd0f1fdaf
--- /dev/null
+++ b/src/test/ui/sized/coinductive-1.rs
@@ -0,0 +1,14 @@
+// check-pass
+struct Node<C: Trait<Self>>(C::Assoc);
+
+trait Trait<T> {
+    type Assoc;
+}
+
+impl<T> Trait<T> for Vec<()> {
+    type Assoc = Vec<T>;
+}
+
+fn main() {
+    let _ = Node::<Vec<()>>(Vec::new());
+}
diff --git a/src/test/ui/sized/coinductive-2.rs b/src/test/ui/sized/coinductive-2.rs
new file mode 100644
index 00000000000..212274d2e4b
--- /dev/null
+++ b/src/test/ui/sized/coinductive-2.rs
@@ -0,0 +1,28 @@
+// run-pass
+struct Node<C: CollectionFactory<Self>> {
+    _children: C::Collection,
+}
+
+trait CollectionFactory<T> {
+    type Collection;
+}
+
+impl<T> CollectionFactory<T> for Vec<()> {
+    type Collection = Vec<T>;
+}
+
+trait Collection<T>: Sized {
+    fn push(&mut self, v: T);
+}
+
+impl<T> Collection<T> for Vec<T> {
+    fn push(&mut self, v: T) {
+        self.push(v)
+    }
+}
+
+fn main() {
+    let _ = Node::<Vec<()>> {
+        _children: Vec::new(),
+    };
+}