1 files changed, 19 insertions, 0 deletions
diff --git a/tests/ui/pattern/deref-patterns/implicit-const-deref.rs b/tests/ui/pattern/deref-patterns/implicit-const-deref.rs
new file mode 100644
index 00000000000..70f89629bc2
--- /dev/null
+++ b/tests/ui/pattern/deref-patterns/implicit-const-deref.rs
@@ -0,0 +1,19 @@
+//! Test that we get an error about structural equality rather than a type error when attempting to
+//! use const patterns of library pointer types. Currently there aren't any smart pointers that can
+//! be used in constant patterns, but we still need to make sure we don't implicitly dereference the
+//! scrutinee and end up with a type error; this would prevent us from reporting that only constants
+//! supporting structural equality can be used as patterns.
+#![feature(deref_patterns)]
+#![allow(incomplete_features)]
+
+const EMPTY: Vec<()> = Vec::new();
+
+fn main() {
+    // FIXME(inline_const_pat): if `inline_const_pat` is reinstated, there should be a case here for
+    // inline const block patterns as well; they're checked differently than named constants.
+    match vec![()] {
+        EMPTY => {}
+        //~^ ERROR: constant of non-structural type `Vec<()>` in a pattern
+        _ => {}
+    }
+}