Implemented #[doc(cfg(...))].

This attribute has two effects:

1. Items with this attribute and their children will have the "This is
   supported on **** only" message attached in the documentation.

2. The items' doc tests will be skipped if the configuration does not
   match.

2 files changed, 59 insertions, 0 deletions

diff --git a/src/test/compile-fail/feature-gate-doc_cfg.rs b/src/test/compile-fail/feature-gate-doc_cfg.rs
new file mode 100644
index 00000000000..1a77d918014
--- /dev/null
+++ b/src/test/compile-fail/feature-gate-doc_cfg.rs
@@ -0,0 +1,12 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[doc(cfg(unix))] //~ ERROR: #[doc(cfg(...))] is experimental
+fn main() {}
diff --git a/src/test/rustdoc/doc-cfg.rs b/src/test/rustdoc/doc-cfg.rs
new file mode 100644
index 00000000000..cfb37912fe7
--- /dev/null
+++ b/src/test/rustdoc/doc-cfg.rs
@@ -0,0 +1,47 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![feature(doc_cfg)]
+
+// @has doc_cfg/struct.Portable.html
+// @!has - '//*[@id="main"]/*[@class="stability"]/*[@class="stab portability"]' ''
+// @has - '//*[@id="method.unix_and_arm_only_function"]' 'fn unix_and_arm_only_function()'
+// @has - '//*[@class="stab portability"]' 'This is supported on Unix and ARM only.'
+pub struct Portable;
+
+// @has doc_cfg/unix_only/index.html \
+//  '//*[@id="main"]/*[@class="stability"]/*[@class="stab portability"]' \
+//  'This is supported on Unix only.'
+// @matches - '//*[@class=" module-item"]//*[@class="stab portability"]' '\AUnix\Z'
+// @matches - '//*[@class=" module-item"]//*[@class="stab portability"]' '\AUnix and ARM\Z'
+// @count - '//*[@class="stab portability"]' 3
+#[doc(cfg(unix))]
+pub mod unix_only {
+    // @has doc_cfg/unix_only/fn.unix_only_function.html \
+    //  '//*[@id="main"]/*[@class="stability"]/*[@class="stab portability"]' \
+    //  'This is supported on Unix only.'
+    // @count - '//*[@class="stab portability"]' 1
+    pub fn unix_only_function() {
+        content::should::be::irrelevant();
+    }
+
+    // @has doc_cfg/unix_only/trait.ArmOnly.html \
+    //  '//*[@id="main"]/*[@class="stability"]/*[@class="stab portability"]' \
+    //  'This is supported on Unix and ARM only.'
+    // @count - '//*[@class="stab portability"]' 2
+    #[doc(cfg(target_arch = "arm"))]
+    pub trait ArmOnly {
+        fn unix_and_arm_only_function();
+    }
+
+    impl ArmOnly for super::Portable {
+        fn unix_and_arm_only_function() {}
+    }
+}
\ No newline at end of file