Merge hir::CaptureClause into ast::CaptureBy.

src/librustc/hir/lowering/expr.rs

@@ -473,7 +473,6 @@ impl LoweringContext<'_> {
         async_gen_kind: hir::AsyncGeneratorKind,
         body: impl FnOnce(&mut LoweringContext<'_>) -> hir::Expr,
     ) -> hir::ExprKind {
-        let capture_clause = self.lower_capture_clause(capture_clause);
         let output = match ret_ty {
             Some(ty) => FunctionRetTy::Ty(ty),
             None => FunctionRetTy::Default(span),
@@ -700,7 +699,6 @@ impl LoweringContext<'_> {
                 generator_kind,
                 movability,
             );
-            let capture_clause = this.lower_capture_clause(capture_clause);
             this.current_item = prev;
             hir::ExprKind::Closure(
                 capture_clause,
@@ -712,13 +710,6 @@ impl LoweringContext<'_> {
         })
     }
 
-    fn lower_capture_clause(&mut self, c: CaptureBy) -> hir::CaptureClause {
-        match c {
-            CaptureBy::Value => hir::CaptureByValue,
-            CaptureBy::Ref => hir::CaptureByRef,
-        }
-    }
-
     fn generator_movability_for_fn(
         &mut self,
         decl: &FnDecl,
@@ -807,7 +798,7 @@ impl LoweringContext<'_> {
                 this.expr(fn_decl_span, async_body, ThinVec::new())
             });
             hir::ExprKind::Closure(
-                this.lower_capture_clause(capture_clause),
+                capture_clause,
                 fn_decl,
                 body_id,
                 fn_decl_span,

src/librustc/hir/mod.rs

@@ -3,7 +3,6 @@
 //! [rustc guide]: https://rust-lang.github.io/rustc-guide/hir.html
 
 pub use self::BlockCheckMode::*;
-pub use self::CaptureClause::*;
 pub use self::FunctionRetTy::*;
 pub use self::PrimTy::*;
 pub use self::UnOp::*;
@@ -22,7 +21,7 @@ use syntax_pos::{Span, DUMMY_SP, MultiSpan};
 use syntax::source_map::Spanned;
 use syntax::ast::{self, CrateSugar, Ident, Name, NodeId, AsmDialect};
 use syntax::ast::{Attribute, Label, LitKind, StrStyle, FloatTy, IntTy, UintTy};
-pub use syntax::ast::{Mutability, Constness, Unsafety, Movability};
+pub use syntax::ast::{Mutability, Constness, Unsafety, Movability, CaptureBy};
 use syntax::attr::{InlineAttr, OptimizeAttr};
 use syntax::symbol::{Symbol, kw};
 use syntax::tokenstream::TokenStream;
@@ -1629,7 +1628,7 @@ pub enum ExprKind {
     ///
     /// This may also be a generator literal or an `async block` as indicated by the
     /// `Option<Movability>`.
-    Closure(CaptureClause, P<FnDecl>, BodyId, Span, Option<Movability>),
+    Closure(CaptureBy, P<FnDecl>, BodyId, Span, Option<Movability>),
     /// A block (e.g., `'label: { ... }`).
     Block(P<Block>, Option<Label>),
 
@@ -1820,12 +1819,6 @@ impl fmt::Display for YieldSource {
     }
 }
 
-#[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
-pub enum CaptureClause {
-    CaptureByValue,
-    CaptureByRef,
-}
-
 // N.B., if you change this, you'll probably want to change the corresponding
 // type structure in middle/ty.rs as well.
 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
@@ -2620,7 +2613,7 @@ pub struct Upvar {
     pub span: Span
 }
 
-pub type CaptureModeMap = NodeMap<CaptureClause>;
+pub type CaptureModeMap = NodeMap<CaptureBy>;
 
  // The TraitCandidate's import_ids is empty if the trait is defined in the same module, and
  // has length > 0 if the trait is found through an chain of imports, starting with the

src/librustc/hir/print.rs

@@ -1909,10 +1909,10 @@ impl<'a> State<'a> {
         }
     }
 
-    pub fn print_capture_clause(&mut self, capture_clause: hir::CaptureClause) {
+    pub fn print_capture_clause(&mut self, capture_clause: hir::CaptureBy) {
         match capture_clause {
-            hir::CaptureByValue => self.word_space("move"),
-            hir::CaptureByRef => {},
+            hir::CaptureBy::Value => self.word_space("move"),
+            hir::CaptureBy::Ref => {},
         }
     }
 

src/librustc/ich/impls_syntax.rs

@@ -169,6 +169,7 @@ impl_stable_hash_for!(struct ::syntax::ast::Lifetime { id, ident });
 impl_stable_hash_for!(enum ::syntax::ast::StrStyle { Cooked, Raw(pounds) });
 impl_stable_hash_for!(enum ::syntax::ast::AttrStyle { Outer, Inner });
 impl_stable_hash_for!(enum ::syntax::ast::Movability { Static, Movable });
+impl_stable_hash_for!(enum ::syntax::ast::CaptureBy { Value, Ref });
 
 impl<'a> HashStable<StableHashingContext<'a>> for [ast::Attribute] {
     fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {

src/librustc_typeck/check/closure.rs

@@ -36,7 +36,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub fn check_expr_closure(
         &self,
         expr: &hir::Expr,
-        _capture: hir::CaptureClause,
+        _capture: hir::CaptureBy,
         decl: &'tcx hir::FnDecl,
         body_id: hir::BodyId,
         gen: Option<hir::Movability>,

src/librustc_typeck/check/upvar.rs

@@ -81,7 +81,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         closure_hir_id: hir::HirId,
         span: Span,
         body: &hir::Body,
-        capture_clause: hir::CaptureClause,
+        capture_clause: hir::CaptureBy,
     ) {
         /*!
          * Analysis starting point.
@@ -141,8 +141,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 upvar_list.insert(var_hir_id, upvar_id);
 
                 let capture_kind = match capture_clause {
-                    hir::CaptureByValue => ty::UpvarCapture::ByValue,
-                    hir::CaptureByRef => {
+                    hir::CaptureBy::Value => ty::UpvarCapture::ByValue,
+                    hir::CaptureBy::Ref => {
                         let origin = UpvarRegion(upvar_id, span);
                         let upvar_region = self.next_region_var(origin);
                         let upvar_borrow = ty::UpvarBorrow {