1 files changed, 53 insertions, 0 deletions
diff --git a/tests/ui/rfc-1445-restrict-constants-in-patterns/phantom-data-is-structurally-matchable.rs b/tests/ui/rfc-1445-restrict-constants-in-patterns/phantom-data-is-structurally-matchable.rs
new file mode 100644
index 00000000000..50f91420ce2
--- /dev/null
+++ b/tests/ui/rfc-1445-restrict-constants-in-patterns/phantom-data-is-structurally-matchable.rs
@@ -0,0 +1,53 @@
+// run-pass
+
+// This file checks that `PhantomData` is considered structurally matchable.
+
+use std::marker::PhantomData;
+
+fn main() {
+    let mut count = 0;
+
+    // A type which is not structurally matchable:
+    struct NotSM;
+
+    // And one that is:
+    #[derive(PartialEq, Eq)]
+    struct SM;
+
+    // Check that SM is structural-match:
+    const CSM: SM = SM;
+    match SM {
+        CSM => count += 1,
+    };
+
+    // Check that PhantomData<T> is structural-match even if T is not.
+    const CPD1: PhantomData<NotSM> = PhantomData;
+    match PhantomData {
+        CPD1 => count += 1,
+    };
+
+    // Check that PhantomData<T> is structural-match when T is.
+    const CPD2: PhantomData<SM> = PhantomData;
+    match PhantomData {
+        CPD2 => count += 1,
+    };
+
+    // Check that a type which has a PhantomData is structural-match.
+    #[derive(PartialEq, Eq, Default)]
+    struct Foo {
+        alpha: PhantomData<NotSM>,
+        beta: PhantomData<SM>,
+    }
+
+    const CFOO: Foo = Foo {
+        alpha: PhantomData,
+        beta: PhantomData,
+    };
+
+    match Foo::default() {
+        CFOO => count += 1,
+    };
+
+    // Final count must be 4 now if all
+    assert_eq!(count, 4);
+}