fix(features): Make lints not enable other nightly-requiring features

Cargo.toml

@@ -35,7 +35,7 @@ suggestions = ["strsim"]
 color       = ["ansi_term", "libc"]
 yaml        = ["yaml-rust"]
 wrap_help   = ["libc", "term_size"]
-lints       = ["clippy", "nightly"]
+lints       = ["clippy"] # Requires nightly Rust
 nightly     = [] # for building with nightly and unstable features
 unstable    = [] # for building with unstable features on stable Rust
 debug       = [] # for building with debug messages

src/lib.rs

@@ -381,10 +381,6 @@
 //! `clap` is licensed under the MIT license. Please read the [LICENSE-MIT](LICENSE-MIT) file in this repository for more information.
 
 #![crate_type= "lib"]
-#![cfg_attr(feature = "nightly", feature(plugin))]
-#![cfg_attr(feature = "lints", plugin(clippy))]
-#![cfg_attr(feature = "lints", deny(warnings))]
-#![cfg_attr(not(any(feature = "lints", feature = "nightly")), deny(unstable_features))]
 #![deny(
         missing_docs,
         missing_debug_implementations,
@@ -394,6 +390,10 @@
         unused_import_braces,
         unused_allocation,
         unused_qualifications)]
+#![cfg_attr(not(any(feature = "lints", feature = "nightly")), forbid(unstable_features))]
+#![cfg_attr(feature = "lints", feature(plugin))]
+#![cfg_attr(feature = "lints", plugin(clippy))]
+#![cfg_attr(feature = "lints", deny(warnings))]
 // clippy false positives, or ones we're ok with...
 #![cfg_attr(feature = "lints", allow(cyclomatic_complexity))]
 #![cfg_attr(feature = "lints", allow(doc_markdown))]