[Syntax Breaking] Rename DefaultImpl to AutoImpl

DefaultImpl is a highly confusing name for what we now call auto impls,
as in `impl Send for ..`. The name auto impl is not formally decided
but for sanity anything is better than `DefaultImpl` which refers
neither to `default impl` nor to `impl Default`.

Author: leoyvens

src/librustc/dep_graph/dep_node.rs

@@ -498,7 +498,7 @@ define_dep_nodes!( <'tcx>
     [] SuperPredicatesOfItem(DefId),
     [] TraitDefOfItem(DefId),
     [] AdtDefOfItem(DefId),
-    [] IsDefaultImpl(DefId),
+    [] IsAutoImpl(DefId),
     [] ImplTraitRef(DefId),
     [] ImplPolarity(DefId),
     [] ClosureKind(DefId),

src/librustc/hir/intravisit.rs

@@ -503,7 +503,7 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item) {
             // visit_enum_def() takes care of visiting the Item's NodeId
             visitor.visit_enum_def(enum_definition, type_parameters, item.id, item.span)
         }
-        ItemDefaultImpl(_, ref trait_ref) => {
+        ItemAutoImpl(_, ref trait_ref) => {
             visitor.visit_id(item.id);
             visitor.visit_trait_ref(trait_ref)
         }

src/librustc/hir/lowering.rs

@@ -96,7 +96,7 @@ pub struct LoweringContext<'a> {
     exported_macros: Vec<hir::MacroDef>,
 
     trait_impls: BTreeMap<DefId, Vec<NodeId>>,
-    trait_default_impl: BTreeMap<DefId, NodeId>,
+    trait_auto_impl: BTreeMap<DefId, NodeId>,
 
     is_generator: bool,
 
@@ -146,7 +146,7 @@ pub fn lower_crate(sess: &Session,
         impl_items: BTreeMap::new(),
         bodies: BTreeMap::new(),
         trait_impls: BTreeMap::new(),
-        trait_default_impl: BTreeMap::new(),
+        trait_auto_impl: BTreeMap::new(),
         exported_macros: Vec::new(),
         catch_scopes: Vec::new(),
         loop_scopes: Vec::new(),
@@ -284,7 +284,7 @@ impl<'a> LoweringContext<'a> {
             bodies: self.bodies,
             body_ids,
             trait_impls: self.trait_impls,
-            trait_default_impl: self.trait_default_impl,
+            trait_auto_impl: self.trait_auto_impl,
         }
     }
 
@@ -1479,14 +1479,14 @@ impl<'a> LoweringContext<'a> {
                 let vdata = self.lower_variant_data(vdata);
                 hir::ItemUnion(vdata, self.lower_generics(generics))
             }
-            ItemKind::DefaultImpl(unsafety, ref trait_ref) => {
+            ItemKind::AutoImpl(unsafety, ref trait_ref) => {
                 let trait_ref = self.lower_trait_ref(trait_ref);
 
                 if let Def::Trait(def_id) = trait_ref.path.def {
-                    self.trait_default_impl.insert(def_id, id);
+                    self.trait_auto_impl.insert(def_id, id);
                 }
 
-                hir::ItemDefaultImpl(self.lower_unsafety(unsafety),
+                hir::ItemAutoImpl(self.lower_unsafety(unsafety),
                                      trait_ref)
             }
             ItemKind::Impl(unsafety,

src/librustc/hir/map/collector.rs

@@ -71,7 +71,7 @@ impl<'a, 'hir> NodeCollector<'a, 'hir> {
                 impl_items: _,
                 bodies: _,
                 trait_impls: _,
-                trait_default_impl: _,
+                trait_auto_impl: _,
                 body_ids: _,
             } = *krate;
 

src/librustc/hir/map/def_collector.rs

@@ -104,7 +104,7 @@ impl<'a> visit::Visitor<'a> for DefCollector<'a> {
         // Pick the def data. This need not be unique, but the more
         // information we encapsulate into
         let def_data = match i.node {
-            ItemKind::DefaultImpl(..) | ItemKind::Impl(..) =>
+            ItemKind::AutoImpl(..) | ItemKind::Impl(..) =>
                 DefPathData::Impl,
             ItemKind::Enum(..) | ItemKind::Struct(..) | ItemKind::Union(..) | ItemKind::Trait(..) |
             ItemKind::ExternCrate(..) | ItemKind::ForeignMod(..) | ItemKind::Ty(..) =>

src/librustc/hir/map/mod.rs

@@ -474,16 +474,16 @@ impl<'hir> Map<'hir> {
         self.forest.krate.trait_impls.get(&trait_did).map_or(&[], |xs| &xs[..])
     }
 
-    pub fn trait_default_impl(&self, trait_did: DefId) -> Option<NodeId> {
+    pub fn trait_auto_impl(&self, trait_did: DefId) -> Option<NodeId> {
         self.dep_graph.read(DepNode::new_no_params(DepKind::AllLocalTraitImpls));
 
         // NB: intentionally bypass `self.forest.krate()` so that we
         // do not trigger a read of the whole krate here
-        self.forest.krate.trait_default_impl.get(&trait_did).cloned()
+        self.forest.krate.trait_auto_impl.get(&trait_did).cloned()
     }
 
     pub fn trait_is_auto(&self, trait_did: DefId) -> bool {
-        self.trait_default_impl(trait_did).is_some()
+        self.trait_auto_impl(trait_did).is_some()
     }
 
     /// Get the attributes on the krate. This is preferable to
@@ -1140,7 +1140,7 @@ fn node_id_to_string(map: &Map, id: NodeId, include_id: bool) -> String {
                 ItemUnion(..) => "union",
                 ItemTrait(..) => "trait",
                 ItemImpl(..) => "impl",
-                ItemDefaultImpl(..) => "default impl",
+                ItemAutoImpl(..) => "default impl",
             };
             format!("{} {}{}", item_str, path_str(), id_str)
         }

src/librustc/hir/mod.rs

@@ -499,7 +499,7 @@ pub struct Crate {
     pub impl_items: BTreeMap<ImplItemId, ImplItem>,
     pub bodies: BTreeMap<BodyId, Body>,
     pub trait_impls: BTreeMap<DefId, Vec<NodeId>>,
-    pub trait_default_impl: BTreeMap<DefId, NodeId>,
+    pub trait_auto_impl: BTreeMap<DefId, NodeId>,
 
     /// A list of the body ids written out in the order in which they
     /// appear in the crate. If you're going to process all the bodies
@@ -1813,10 +1813,10 @@ pub enum Item_ {
     /// Represents a Trait Declaration
     ItemTrait(Unsafety, Generics, TyParamBounds, HirVec<TraitItemRef>),
 
-    // Default trait implementations
+    /// Auto trait implementations
     ///
     /// `impl Trait for .. {}`
-    ItemDefaultImpl(Unsafety, TraitRef),
+    ItemAutoImpl(Unsafety, TraitRef),
     /// An implementation, eg `impl<A> Trait for Foo { .. }`
     ItemImpl(Unsafety,
              ImplPolarity,
@@ -1844,7 +1844,7 @@ impl Item_ {
             ItemUnion(..) => "union",
             ItemTrait(..) => "trait",
             ItemImpl(..) |
-            ItemDefaultImpl(..) => "item",
+            ItemAutoImpl(..) => "item",
         }
     }
 

src/librustc/hir/print.rs

@@ -660,7 +660,7 @@ impl<'a> State<'a> {
                 self.head(&visibility_qualified(&item.vis, "union"))?;
                 self.print_struct(struct_def, generics, item.name, item.span, true)?;
             }
-            hir::ItemDefaultImpl(unsafety, ref trait_ref) => {
+            hir::ItemAutoImpl(unsafety, ref trait_ref) => {
                 self.head("")?;
                 self.print_visibility(&item.vis)?;
                 self.print_unsafety(unsafety)?;

src/librustc/ich/impls_hir.rs

@@ -898,7 +898,7 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for hir::Item {
             hir::ItemForeignMod(..)  |
             hir::ItemGlobalAsm(..)   |
             hir::ItemMod(..)         |
-            hir::ItemDefaultImpl(..) |
+            hir::ItemAutoImpl(..) |
             hir::ItemTrait(..)       |
             hir::ItemImpl(..)        |
             hir::ItemTy(..)          |
@@ -945,7 +945,7 @@ impl_stable_hash_for!(enum hir::Item_ {
     ItemStruct(variant_data, generics),
     ItemUnion(variant_data, generics),
     ItemTrait(unsafety, generics, bounds, item_refs),
-    ItemDefaultImpl(unsafety, trait_ref),
+    ItemAutoImpl(unsafety, trait_ref),
     ItemImpl(unsafety, impl_polarity, impl_defaultness, generics, trait_ref, ty, impl_item_refs)
 });
 

src/librustc/ich/impls_ty.rs

@@ -731,13 +731,13 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for ty::TraitDef {
             def_id: _,
             unsafety,
             paren_sugar,
-            has_default_impl,
+            has_auto_impl,
             def_path_hash,
         } = *self;
 
         unsafety.hash_stable(hcx, hasher);
         paren_sugar.hash_stable(hcx, hasher);
-        has_default_impl.hash_stable(hcx, hasher);
+        has_auto_impl.hash_stable(hcx, hasher);
         def_path_hash.hash_stable(hcx, hasher);
     }
 }