add test for rejecting EIIs in statement position

Author: jdonszelmann

tests/ui/eii/error_statement_position.rs

@@ -13,4 +13,10 @@ fn main() {
     #[eii]
     //~^ ERROR `#[eii]` is only valid on functions
     impl Bar {}
+
+
+    // Even on functions, eiis in statement position are rejected
+    #[eii]
+    //~^ ERROR `#[eii]` can only be used on functions inside a module
+    fn foo() {}
 }

tests/ui/eii/error_statement_position.stderr

@@ -4,5 +4,14 @@ error: `#[eii]` is only valid on functions
 LL |     #[eii]
    |     ^^^^^^
 
-error: aborting due to 1 previous error
+error: `#[eii]` can only be used on functions inside a module
+  --> $DIR/error_statement_position.rs:19:5
+   |
+LL |     #[eii]
+   |     ^^^^^^
+LL |
+LL |     fn foo() {}
+   |        --- `#[eii]` is used on this item, which is part of another item's local scope
+
+error: aborting due to 2 previous errors