1 files changed, 67 insertions, 0 deletions
diff --git a/src/test/ui/lint/lint-enum-intrinsics-non-enums.rs b/src/test/ui/lint/lint-enum-intrinsics-non-enums.rs
new file mode 100644
index 000000000..8ad337064
--- /dev/null
+++ b/src/test/ui/lint/lint-enum-intrinsics-non-enums.rs
@@ -0,0 +1,67 @@
+// Test the enum_intrinsics_non_enums lint.
+
+#![feature(variant_count)]
+
+use std::mem::{discriminant, variant_count};
+
+enum SomeEnum {
+    A,
+    B,
+}
+
+struct SomeStruct;
+
+fn generic_discriminant<T>(v: &T) {
+    discriminant::<T>(v);
+}
+
+fn generic_variant_count<T>() -> usize {
+    variant_count::<T>()
+}
+
+fn test_discriminant() {
+    discriminant(&SomeEnum::A);
+    generic_discriminant(&SomeEnum::B);
+
+    discriminant(&());
+    //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type
+
+    discriminant(&&SomeEnum::B);
+    //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type
+
+    discriminant(&SomeStruct);
+    //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type
+
+    discriminant(&123u32);
+    //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type
+
+    discriminant(&&123i8);
+    //~^ error: the return value of `mem::discriminant` is unspecified when called with a non-enum type
+}
+
+fn test_variant_count() {
+    variant_count::<SomeEnum>();
+    generic_variant_count::<SomeEnum>();
+
+    variant_count::<&str>();
+    //~^ error: the return value of `mem::variant_count` is unspecified when called with a non-enum type
+
+    variant_count::<*const u8>();
+    //~^ error: the return value of `mem::variant_count` is unspecified when called with a non-enum type
+
+    variant_count::<()>();
+    //~^ error: the return value of `mem::variant_count` is unspecified when called with a non-enum type
+
+    variant_count::<&SomeEnum>();
+    //~^ error: the return value of `mem::variant_count` is unspecified when called with a non-enum type
+}
+
+fn main() {
+    test_discriminant();
+    test_variant_count();
+
+    // The lint ignores cases where the type is generic, so these should be
+    // allowed even though their return values are unspecified
+    generic_variant_count::<SomeStruct>();
+    generic_discriminant::<SomeStruct>(&SomeStruct);
+}