1 files changed, 74 insertions, 0 deletions
diff --git a/tests/ui/feature-gates/feature-gate-never_patterns.rs b/tests/ui/feature-gates/feature-gate-never_patterns.rs
new file mode 100644
index 000000000..f39106223
--- /dev/null
+++ b/tests/ui/feature-gates/feature-gate-never_patterns.rs
@@ -0,0 +1,74 @@
+// Check that never patterns require the feature gate.
+use std::ptr::NonNull;
+
+enum Void {}
+
+fn main() {
+    let res: Result<u32, Void> = Ok(0);
+    let (Ok(_x) | Err(&!)) = res.as_ref();
+    //~^ ERROR `!` patterns are experimental
+    //~| ERROR: is not bound in all patterns
+
+    unsafe {
+        let ptr: *const Void = NonNull::dangling().as_ptr();
+        match *ptr {
+            !
+            //~^ ERROR `!` patterns are experimental
+        }
+        // Check that the gate operates even behind `cfg`.
+        #[cfg(FALSE)]
+        match *ptr {
+            !
+            //~^ ERROR `!` patterns are experimental
+        }
+        #[cfg(FALSE)]
+        match *ptr {
+            ! => {}
+            //~^ ERROR `!` patterns are experimental
+        }
+    }
+
+    // Correctly gate match arms with no body.
+    match Some(0) {
+        None => {}
+        Some(_),
+        //~^ ERROR unexpected `,` in pattern
+    }
+    match Some(0) {
+        None => {}
+        Some(_)
+        //~^ ERROR `match` arm with no body
+    }
+    match Some(0) {
+        _ => {}
+        Some(_) if false,
+        //~^ ERROR `match` arm with no body
+        Some(_) if false
+        //~^ ERROR `match` arm with no body
+    }
+    match res {
+        Ok(_) => {}
+        Err(!),
+        //~^ ERROR `!` patterns are experimental
+    }
+    match res {
+        Err(!) if false,
+        //~^ ERROR `!` patterns are experimental
+        //~| ERROR a guard on a never pattern will never be run
+        _ => {}
+    }
+
+    // Check that the gate operates even behind `cfg`.
+    match Some(0) {
+        None => {}
+        #[cfg(FALSE)]
+        Some(_)
+        //~^ ERROR `match` arm with no body
+    }
+    match Some(0) {
+        _ => {}
+        #[cfg(FALSE)]
+        Some(_) if false
+        //~^ ERROR `match` arm with no body
+    }
+}