Rollup merge of #34339 - jseyfried:thin_vec, r=petrochenkov,Manishearth

Generalize and abstract `ThinAttributes` to `ThinVec<Attribute>`.

Author: jseyfried

src/librustc/hir/fold.rs

@@ -14,7 +14,6 @@
 use hir::*;
 use syntax::ast::{Name, NodeId, DUMMY_NODE_ID, Attribute, Attribute_, MetaItem};
 use syntax::ast::MetaItemKind;
-use syntax::attr::ThinAttributesExt;
 use hir;
 use syntax_pos::Span;
 use syntax::codemap::{respan, Spanned};
@@ -293,8 +292,11 @@ pub fn noop_fold_view_path<T: Folder>(view_path: P<ViewPath>, fld: &mut T) -> P<
     })
 }
 
-pub fn fold_attrs<T: Folder>(attrs: HirVec<Attribute>, fld: &mut T) -> HirVec<Attribute> {
-    attrs.move_flat_map(|x| fld.fold_attribute(x))
+pub fn fold_attrs<T, F>(attrs: T, fld: &mut F) -> T
+    where T: Into<Vec<Attribute>> + From<Vec<Attribute>>,
+          F: Folder,
+{
+    attrs.into().move_flat_map(|x| fld.fold_attribute(x)).into()
 }
 
 pub fn noop_fold_arm<T: Folder>(Arm { attrs, pats, guard, body }: Arm, fld: &mut T) -> Arm {
@@ -462,7 +464,7 @@ pub fn noop_fold_local<T: Folder>(l: P<Local>, fld: &mut T) -> P<Local> {
             pat: fld.fold_pat(pat),
             init: init.map(|e| fld.fold_expr(e)),
             span: fld.new_span(span),
-            attrs: attrs.map_thin_attrs(|attrs| fold_attrs(attrs.into(), fld).into()),
+            attrs: fold_attrs(attrs, fld),
         }
     })
 }
@@ -1079,7 +1081,7 @@ pub fn noop_fold_expr<T: Folder>(Expr { id, node, span, attrs }: Expr, folder: &
             }
         },
         span: folder.new_span(span),
-        attrs: attrs.map_thin_attrs(|attrs| fold_attrs(attrs.into(), folder).into()),
+        attrs: fold_attrs(attrs, folder),
     }
 }
 

src/librustc/hir/intravisit.rs

@@ -27,7 +27,6 @@
 
 use syntax::abi::Abi;
 use syntax::ast::{NodeId, CRATE_NODE_ID, Name, Attribute};
-use syntax::attr::ThinAttributesExt;
 use syntax::codemap::Spanned;
 use syntax_pos::Span;
 use hir::*;
@@ -757,7 +756,7 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr) {
             walk_list!(visitor, visit_arm, arms);
         }
         ExprClosure(_, ref function_declaration, ref body, _fn_decl_span) => {
-            visitor.visit_fn(FnKind::Closure(expression.attrs.as_attr_slice()),
+            visitor.visit_fn(FnKind::Closure(&expression.attrs),
                              function_declaration,
                              body,
                              expression.span,

src/librustc/hir/lowering.rs

@@ -27,7 +27,6 @@ use hir::map::{self, Node};
 use syntax::abi;
 use hir::{Block, FnDecl};
 use syntax::ast::{Attribute, Name, NodeId};
-use syntax::attr::ThinAttributesExt;
 use hir as ast;
 use syntax_pos::Span;
 use hir::intravisit::FnKind;
@@ -257,11 +256,7 @@ impl<'a> FnLikeNode<'a> {
             }
             map::NodeExpr(e) => match e.node {
                 ast::ExprClosure(_, ref decl, ref block, _fn_decl_span) =>
-                    closure(ClosureParts::new(&decl,
-                                              &block,
-                                              e.id,
-                                              e.span,
-                                              e.attrs.as_attr_slice())),
+                    closure(ClosureParts::new(&decl, &block, e.id, e.span, &e.attrs)),
                 _ => bug!("expr FnLikeNode that is not fn-like"),
             },
             _ => bug!("other FnLikeNode that is not fn-like"),

src/librustc/hir/map/blocks.rs

@@ -23,7 +23,6 @@ use hir::def_id::{CRATE_DEF_INDEX, DefId, DefIndex};
 
 use syntax::abi::Abi;
 use syntax::ast::{self, Name, NodeId, DUMMY_NODE_ID, };
-use syntax::attr::ThinAttributesExt;
 use syntax::codemap::Spanned;
 use syntax::visit;
 use syntax_pos::Span;
@@ -578,7 +577,7 @@ impl<'ast> Map<'ast> {
             Some(NodeTraitItem(ref ti)) => Some(&ti.attrs[..]),
             Some(NodeImplItem(ref ii)) => Some(&ii.attrs[..]),
             Some(NodeVariant(ref v)) => Some(&v.node.attrs[..]),
-            Some(NodeExpr(ref e)) => Some(e.attrs.as_attr_slice()),
+            Some(NodeExpr(ref e)) => Some(&*e.attrs),
             Some(NodeStmt(ref s)) => Some(s.node.attrs()),
             // unit/tuple structs take the attributes straight from
             // the struct definition.

src/librustc/hir/map/mod.rs

@@ -41,10 +41,10 @@ use syntax::codemap::{self, respan, Spanned};
 use syntax::abi::Abi;
 use syntax::ast::{Name, NodeId, DUMMY_NODE_ID, AsmDialect};
 use syntax::ast::{Attribute, Lit, StrStyle, FloatTy, IntTy, UintTy, MetaItem};
-use syntax::attr::{ThinAttributes, ThinAttributesExt};
 use syntax::parse::token::{keywords, InternedString};
 use syntax::ptr::P;
 use syntax::tokenstream::TokenTree;
+use syntax::util::ThinVec;
 
 use std::collections::BTreeMap;
 use std::fmt;
@@ -734,7 +734,7 @@ impl Stmt_ {
         match *self {
             StmtDecl(ref d, _) => d.node.attrs(),
             StmtExpr(ref e, _) |
-            StmtSemi(ref e, _) => e.attrs.as_attr_slice(),
+            StmtSemi(ref e, _) => &e.attrs,
         }
     }
 
@@ -758,7 +758,7 @@ pub struct Local {
     pub init: Option<P<Expr>>,
     pub id: NodeId,
     pub span: Span,
-    pub attrs: ThinAttributes,
+    pub attrs: ThinVec<Attribute>,
 }
 
 pub type Decl = Spanned<Decl_>;
@@ -774,7 +774,7 @@ pub enum Decl_ {
 impl Decl_ {
     pub fn attrs(&self) -> &[Attribute] {
         match *self {
-            DeclLocal(ref l) => l.attrs.as_attr_slice(),
+            DeclLocal(ref l) => &l.attrs,
             DeclItem(_) => &[]
         }
     }
@@ -819,7 +819,7 @@ pub struct Expr {
     pub id: NodeId,
     pub node: Expr_,
     pub span: Span,
-    pub attrs: ThinAttributes,
+    pub attrs: ThinVec<Attribute>,
 }
 
 impl fmt::Debug for Expr {

src/librustc/hir/mod.rs

@@ -42,7 +42,6 @@ use std::mem;
 use syntax::attr::{self, AttrMetaMethods};
 use syntax::parse::token::InternedString;
 use syntax::ast;
-use syntax::attr::ThinAttributesExt;
 use syntax_pos::Span;
 use errors::DiagnosticBuilder;
 use hir;
@@ -767,7 +766,7 @@ impl<'a, 'tcx, 'v> hir_visit::Visitor<'v> for LateContext<'a, 'tcx> {
     }
 
     fn visit_expr(&mut self, e: &hir::Expr) {
-        self.with_lint_attrs(e.attrs.as_attr_slice(), |cx| {
+        self.with_lint_attrs(&e.attrs, |cx| {
             run_lints!(cx, check_expr, late_passes, e);
             hir_visit::walk_expr(cx, e);
         })
@@ -832,7 +831,7 @@ impl<'a, 'tcx, 'v> hir_visit::Visitor<'v> for LateContext<'a, 'tcx> {
     }
 
     fn visit_local(&mut self, l: &hir::Local) {
-        self.with_lint_attrs(l.attrs.as_attr_slice(), |cx| {
+        self.with_lint_attrs(&l.attrs, |cx| {
             run_lints!(cx, check_local, late_passes, l);
             hir_visit::walk_local(cx, l);
         })
@@ -928,7 +927,7 @@ impl<'a> ast_visit::Visitor for EarlyContext<'a> {
     }
 
     fn visit_expr(&mut self, e: &ast::Expr) {
-        self.with_lint_attrs(e.attrs.as_attr_slice(), |cx| {
+        self.with_lint_attrs(&e.attrs, |cx| {
             run_lints!(cx, check_expr, early_passes, e);
             ast_visit::walk_expr(cx, e);
         })
@@ -988,7 +987,7 @@ impl<'a> ast_visit::Visitor for EarlyContext<'a> {
     }
 
     fn visit_local(&mut self, l: &ast::Local) {
-        self.with_lint_attrs(l.attrs.as_attr_slice(), |cx| {
+        self.with_lint_attrs(&l.attrs, |cx| {
             run_lints!(cx, check_local, early_passes, l);
             ast_visit::walk_local(cx, l);
         })

src/librustc/lint/context.rs

@@ -452,7 +452,7 @@ fn const_val_to_expr(value: &ConstVal) -> P<hir::Expr> {
         id: 0,
         node: hir::ExprLit(P(Spanned { node: node, span: DUMMY_SP })),
         span: DUMMY_SP,
-        attrs: None,
+        attrs: ast::ThinVec::new(),
     })
 }
 

src/librustc_const_eval/check_match.rs

@@ -672,7 +672,7 @@ impl fold::Folder for ReplaceBodyWithLoop {
                 node: ast::ExprKind::Loop(empty_block, None),
                 id: ast::DUMMY_NODE_ID,
                 span: syntax_pos::DUMMY_SP,
-                attrs: None,
+                attrs: ast::ThinVec::new(),
             });
 
             expr_to_block(b.rules, Some(loop_expr))

src/librustc_driver/pretty.rs

@@ -14,8 +14,8 @@ pub use self::TyParamBound::*;
 pub use self::UnsafeSource::*;
 pub use self::ViewPath_::*;
 pub use self::PathParameters::*;
+pub use util::ThinVec;
 
-use attr::ThinAttributes;
 use syntax_pos::{mk_sp, Span, DUMMY_SP, ExpnId};
 use codemap::{respan, Spanned};
 use abi::Abi;
@@ -835,10 +835,9 @@ pub enum StmtKind {
     /// Expr without trailing semi-colon (must have unit type).
     Expr(P<Expr>),
 
-    /// Expr with trailing semi-colon (may have any type).
     Semi(P<Expr>),
 
-    Mac(P<(Mac, MacStmtStyle, ThinAttributes)>),
+    Mac(P<(Mac, MacStmtStyle, ThinVec<Attribute>)>),
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
@@ -865,7 +864,7 @@ pub struct Local {
     pub init: Option<P<Expr>>,
     pub id: NodeId,
     pub span: Span,
-    pub attrs: ThinAttributes,
+    pub attrs: ThinVec<Attribute>,
 }
 
 /// An arm of a 'match'.
@@ -913,7 +912,7 @@ pub struct Expr {
     pub id: NodeId,
     pub node: ExprKind,
     pub span: Span,
-    pub attrs: ThinAttributes
+    pub attrs: ThinVec<Attribute>
 }
 
 impl fmt::Debug for Expr {