1 files changed, 50 insertions, 0 deletions
diff --git a/compiler/rustc_data_structures/src/tagged_ptr/copy/tests.rs b/compiler/rustc_data_structures/src/tagged_ptr/copy/tests.rs
new file mode 100644
index 000000000..bfcc2e603
--- /dev/null
+++ b/compiler/rustc_data_structures/src/tagged_ptr/copy/tests.rs
@@ -0,0 +1,50 @@
+use std::ptr;
+
+use crate::stable_hasher::{HashStable, StableHasher};
+use crate::tagged_ptr::{CopyTaggedPtr, Pointer, Tag, Tag2};
+
+#[test]
+fn smoke() {
+    let value = 12u32;
+    let reference = &value;
+    let tag = Tag2::B01;
+
+    let ptr = tag_ptr(reference, tag);
+
+    assert_eq!(ptr.tag(), tag);
+    assert_eq!(*ptr, 12);
+    assert!(ptr::eq(ptr.pointer(), reference));
+
+    let copy = ptr;
+
+    let mut ptr = ptr;
+    ptr.set_tag(Tag2::B00);
+    assert_eq!(ptr.tag(), Tag2::B00);
+
+    assert_eq!(copy.tag(), tag);
+    assert_eq!(*copy, 12);
+    assert!(ptr::eq(copy.pointer(), reference));
+}
+
+#[test]
+fn stable_hash_hashes_as_tuple() {
+    let hash_packed = {
+        let mut hasher = StableHasher::new();
+        tag_ptr(&12, Tag2::B11).hash_stable(&mut (), &mut hasher);
+
+        hasher.finalize()
+    };
+
+    let hash_tupled = {
+        let mut hasher = StableHasher::new();
+        (&12, Tag2::B11).hash_stable(&mut (), &mut hasher);
+        hasher.finalize()
+    };
+
+    assert_eq!(hash_packed, hash_tupled);
+}
+
+/// Helper to create tagged pointers without specifying `COMPARE_PACKED` if it does not matter.
+fn tag_ptr<P: Pointer, T: Tag>(ptr: P, tag: T) -> CopyTaggedPtr<P, T, true> {
+    CopyTaggedPtr::new(ptr, tag)
+}