Enable proc_macro_non_items in doc tests

Author: dtolnay

src/lib.rs

@@ -20,7 +20,7 @@
 //! # Using Indoc
 //!
 //! ```rust
-#![cfg_attr(feature = "unstable", doc = " #![feature(proc_macro)]")]
+#![cfg_attr(feature = "unstable", doc = " #![feature(proc_macro, proc_macro_non_items)]")]
 #![cfg_attr(feature = "unstable", doc = "")]
 #![cfg_attr(not(feature = "unstable"), doc = " #[macro_use]")]
 //! extern crate indoc;
@@ -41,7 +41,7 @@
 //! Indoc also works with raw string literals:
 //!
 //! ```rust
-#![cfg_attr(feature = "unstable", doc = " #![feature(proc_macro)]")]
+#![cfg_attr(feature = "unstable", doc = " #![feature(proc_macro, proc_macro_non_items)]")]
 #![cfg_attr(feature = "unstable", doc = "")]
 #![cfg_attr(not(feature = "unstable"), doc = " #[macro_use]")]
 //! extern crate indoc;
@@ -62,7 +62,7 @@
 //! And byte string literals:
 //!
 //! ```rust
-#![cfg_attr(feature = "unstable", doc = " #![feature(proc_macro)]")]
+#![cfg_attr(feature = "unstable", doc = " #![feature(proc_macro, proc_macro_non_items)]")]
 #![cfg_attr(feature = "unstable", doc = "")]
 #![cfg_attr(not(feature = "unstable"), doc = " #[macro_use]")]
 //! extern crate indoc;