Derive HashStable for TokenKind.

2 files changed, 11 insertions, 13 deletions

diff --git a/src/libsyntax/lib.rs b/src/libsyntax/lib.rs
index 579d2657939..22b49862f49 100644
--- a/src/libsyntax/lib.rs
+++ b/src/libsyntax/lib.rs
@@ -20,7 +20,6 @@
 #![recursion_limit="256"]
 
 pub use errors;
-use rustc_data_structures::stable_hasher::StableHasher;
 use rustc_data_structures::sync::Lock;
 use rustc_index::bit_set::GrowableBitSet;
 pub use rustc_data_structures::thin_vec::ThinVec;
@@ -115,6 +114,4 @@ pub mod early_buffered_lints;
 /// Requirements for a `StableHashingContext` to be used in this crate.
 /// This is a hack to allow using the `HashStable_Generic` derive macro
 /// instead of implementing everything in librustc.
-pub trait HashStableContext: syntax_pos::HashStableContext {
-    fn hash_stable_tokenkind(&mut self, tokenkind: &token::TokenKind, hasher: &mut StableHasher);
-}
+pub trait HashStableContext: syntax_pos::HashStableContext {}
diff --git a/src/libsyntax/token.rs b/src/libsyntax/token.rs
index 045e9f8689f..6f45211ac5f 100644
--- a/src/libsyntax/token.rs
+++ b/src/libsyntax/token.rs
@@ -19,6 +19,7 @@ use rustc_data_structures::sync::Lrc;
 use rustc_macros::HashStable_Generic;
 
 #[derive(Clone, PartialEq, RustcEncodable, RustcDecodable, Hash, Debug, Copy)]
+#[derive(HashStable_Generic)]
 pub enum BinOpToken {
     Plus,
     Minus,
@@ -192,7 +193,7 @@ fn ident_can_begin_type(name: ast::Name, span: Span, is_raw: bool) -> bool {
     ].contains(&name)
 }
 
-#[derive(Clone, PartialEq, RustcEncodable, RustcDecodable, Debug)]
+#[derive(Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable_Generic)]
 pub enum TokenKind {
     /* Expression-operator symbols. */
     Eq,
@@ -264,14 +265,6 @@ pub enum TokenKind {
 #[cfg(target_arch = "x86_64")]
 rustc_data_structures::static_assert_size!(TokenKind, 16);
 
-impl<CTX> HashStable<CTX> for TokenKind
-    where CTX: crate::HashStableContext
-{
-    fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
-        hcx.hash_stable_tokenkind(self, hasher)
-    }
-}
-
 #[derive(Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable_Generic)]
 pub struct Token {
     pub kind: TokenKind,
@@ -735,3 +728,11 @@ impl fmt::Debug for Nonterminal {
         }
     }
 }
+
+impl<CTX> HashStable<CTX> for Nonterminal
+    where CTX: crate::HashStableContext
+{
+    fn hash_stable(&self, _hcx: &mut CTX, _hasher: &mut StableHasher) {
+        panic!("interpolated tokens should not be present in the HIR")
+    }
+}