Ensure macros are not affected

Author: estebank

tests/ui/parser/fake-anon-enums-in-macros.rs

@@ -0,0 +1,20 @@
+// build-pass
+macro_rules! check_ty {
+    ($Z:ty) => { compile_error!("triggered"); };
+    ($X:ty | $Y:ty) => { $X };
+}
+
+macro_rules! check {
+    ($Z:ty) => { compile_error!("triggered"); };
+    ($X:ty | $Y:ty) => { };
+}
+
+check! { i32 | u8 }
+
+fn foo(x: check_ty! { i32 | u8 }) -> check_ty! { i32 | u8 } {
+    x
+}
+fn main() {
+    let x: check_ty! { i32 | u8 } = 42;
+    let _: check_ty! { i32 | u8 } = foo(x);
+}