1 files changed, 56 insertions, 0 deletions
diff --git a/tests/ui/union/union-move.rs b/tests/ui/union/union-move.rs
new file mode 100644
index 000000000..b8b1ac804
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+++ b/tests/ui/union/union-move.rs
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+// revisions: mirunsafeck thirunsafeck
+// [thirunsafeck]compile-flags: -Z thir-unsafeck
+
+//! Test the behavior of moving out of non-`Copy` union fields.
+//! Avoid types that `Drop`, we want to focus on moving.
+
+use std::cell::RefCell;
+use std::mem::ManuallyDrop;
+
+fn move_out<T>(x: T) {}
+
+union U1 {
+    f1_nocopy: ManuallyDrop<RefCell<i32>>,
+    f2_nocopy: ManuallyDrop<RefCell<i32>>,
+    f3_copy: i32,
+}
+
+union U2 {
+    f1_nocopy: ManuallyDrop<RefCell<i32>>,
+}
+impl Drop for U2 {
+    fn drop(&mut self) {}
+}
+
+fn test1(x: U1) {
+    // Moving out of a nocopy field prevents accessing other nocopy field.
+    unsafe {
+        move_out(x.f1_nocopy);
+        move_out(x.f2_nocopy); //~ ERROR use of moved value: `x`
+    }
+}
+
+fn test2(x: U1) {
+    // "Moving" out of copy field doesn't prevent later field accesses.
+    unsafe {
+        move_out(x.f3_copy);
+        move_out(x.f2_nocopy); // no error
+    }
+}
+
+fn test3(x: U1) {
+    // Moving out of a nocopy field prevents accessing other copy field.
+    unsafe {
+        move_out(x.f2_nocopy);
+        move_out(x.f3_copy); //~ ERROR use of moved value: `x`
+    }
+}
+
+fn test4(x: U2) {
+    // Cannot move out of union that implements `Drop`.
+    unsafe {
+        move_out(x.f1_nocopy); //~ ERROR cannot move out of type `U2`, which implements the `Drop`
+    }
+}
+
+fn main() {}