Auto merge of #36678 - TimNN:fix-dist, r=alexcrichton

emit feature help in cheat mode (fix nightlies)

This should fix the `distcheck` failure in the latest nightly.

cc #36539

It's probably not ideal to check the environment that often and the code ist duplicated from `librustc/session/config.rs` but this was the easiest fix I could think of.

A cleaner solution would probably be to move the `unstable_features` from `Options` to `ParseSess` and change the `diag` parameter of `emit_feature_err` to take `ParseSess` instead of a `Handler`.

1 files changed, 3 insertions, 0 deletions

diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 5aa0efdec11..1e286c143de 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -14,6 +14,7 @@ use ast;
 use codemap::CodeMap;
 use syntax_pos::{self, Span, FileMap};
 use errors::{Handler, ColorConfig, DiagnosticBuilder};
+use feature_gate::UnstableFeatures;
 use parse::parser::Parser;
 use parse::token::InternedString;
 use ptr::P;
@@ -42,6 +43,7 @@ pub mod obsolete;
 /// Info about a parsing session.
 pub struct ParseSess {
     pub span_diagnostic: Handler, // better be the same as the one in the reader!
+    pub unstable_features: UnstableFeatures,
     /// Used to determine and report recursive mod inclusions
     included_mod_stack: RefCell<Vec<PathBuf>>,
     code_map: Rc<CodeMap>,
@@ -60,6 +62,7 @@ impl ParseSess {
     pub fn with_span_handler(handler: Handler, code_map: Rc<CodeMap>) -> ParseSess {
         ParseSess {
             span_diagnostic: handler,
+            unstable_features: UnstableFeatures::from_environment(),
             included_mod_stack: RefCell::new(vec![]),
             code_map: code_map
         }