From 542bc75deaaf4e84dcd7a196685bc1a1cb100d32 Mon Sep 17 00:00:00 2001
From: Michael Woerister <michaelwoerister@posteo>
Date: Wed, 14 Feb 2018 16:11:02 +0100
Subject: Turn features() into a query.

---
 src/libsyntax/feature_gate.rs | 7 +++++++
 1 file changed, 7 insertions(+)

(limited to 'src/libsyntax/feature_gate.rs')

diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 058df1d5169..45d82bc7af3 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -62,6 +62,7 @@ macro_rules! declare_features {
             &[$((stringify!($feature), $ver, $issue, set!($feature))),+];
 
         /// A set of features to be used by later passes.
+        #[derive(Clone)]
         pub struct Features {
             /// `#![feature]` attrs for stable language features, for error reporting
             pub declared_stable_lang_features: Vec<(Symbol, Span)>,
@@ -78,6 +79,12 @@ macro_rules! declare_features {
                     $($feature: false),+
                 }
             }
+
+            pub fn walk_feature_fields<F>(&self, mut f: F)
+                where F: FnMut(&str, bool)
+            {
+                $(f(stringify!($feature), self.$feature);)+
+            }
         }
     };
 
-- 
cgit 1.4.1-3-g733a5