Remove Deref/DerefMut impls for RegionConstraintCollector.

`Deref`/`DerefMut` can be useful, but they can also obfuscate. I don't
think they're worth it for `RegionConstraintCollector`. They're also not
present on the similar types `OpaqueTypeTable` and `TypeVariableTable`.

Author: nnethercote

compiler/rustc_infer/src/infer/region_constraints/mod.rs

@@ -61,21 +61,6 @@ pub struct RegionConstraintCollector<'a, 'tcx> {
 undo_log:&'amutInferCtxtUndoLogs<'tcx>,
 }
 
-impl<'tcx> std::ops::DerefforRegionConstraintCollector<'_,'tcx>{
-typeTarget = RegionConstraintStorage<'tcx>;
-#[inline]
-fnderef(&self) -> &RegionConstraintStorage<'tcx>{
-self.storage
-}
-}
-
-impl<'tcx> std::ops::DerefMutforRegionConstraintCollector<'_,'tcx>{
-#[inline]
-fnderef_mut(&mutself) -> &mutRegionConstraintStorage<'tcx>{
-self.storage
-}
-}
-
 pubtypeVarInfos = IndexVec<RegionVid,RegionVariableInfo>;
 
 /// The full set of region constraints gathered up by the collector.
@@ -324,11 +309,11 @@ impl<'tcx> RegionConstraintStorage<'tcx> {
 
 impl<'tcx>RegionConstraintCollector<'_,'tcx>{
 pubfnnum_region_vars(&self) -> usize{
-self.var_infos.len()
+self.storage.var_infos.len()
 }
 
 pubfnregion_constraint_data(&self) -> &RegionConstraintData<'tcx>{
-&self.data
+&self.storage.data
 }
 
 /// Takes (and clears) the current set of constraints. Note that
@@ -384,25 +369,25 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 }
 
 pubfndata(&self) -> &RegionConstraintData<'tcx>{
-&self.data
+&self.storage.data
 }
 
 pub(super)fnstart_snapshot(&mutself) -> RegionSnapshot{
 debug!("RegionConstraintCollector: start_snapshot");
-RegionSnapshot{any_unifications:self.any_unifications}
+RegionSnapshot{any_unifications:self.storage.any_unifications}
 }
 
 pub(super)fnrollback_to(&mutself,snapshot:RegionSnapshot){
 debug!("RegionConstraintCollector: rollback_to({:?})", snapshot);
-self.any_unifications = snapshot.any_unifications;
+self.storage.any_unifications = snapshot.any_unifications;
 }
 
 pub(super)fnnew_region_var(
 &mutself,
 universe: ty::UniverseIndex,
 origin:RegionVariableOrigin,
 ) -> RegionVid{
-let vid = self.var_infos.push(RegionVariableInfo{ origin, universe });
+let vid = self.storage.var_infos.push(RegionVariableInfo{ origin, universe });
 
 let u_vid = self.unification_table_mut().new_key(RegionVariableValue::Unknown{ universe });
 assert_eq!(vid, u_vid.vid);
@@ -413,7 +398,7 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 
 /// Returns the origin for the given variable.
 pub(super)fnvar_origin(&self,vid:RegionVid) -> RegionVariableOrigin{
-self.var_infos[vid].origin
+self.storage.var_infos[vid].origin
 }
 
 fnadd_constraint(&mutself,constraint:Constraint<'tcx>,origin:SubregionOrigin<'tcx>){
@@ -436,8 +421,8 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 return;
 }
 
-let index = self.data.verifys.len();
-self.data.verifys.push(verify);
+let index = self.storage.data.verifys.len();
+self.storage.data.verifys.push(verify);
 self.undo_log.push(AddVerify(index));
 }
 
@@ -457,7 +442,7 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 (ty::ReVar(a), ty::ReVar(b)) => {
 debug!("make_eqregion: unifying {:?} with {:?}", a, b);
 ifself.unification_table_mut().unify_var_var(a, b).is_ok(){
-self.any_unifications = true;
+self.storage.any_unifications = true;
 }
 }
 (ty::ReVar(vid), _) => {
@@ -467,7 +452,7 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 .unify_var_value(vid,RegionVariableValue::Known{value: b })
 .is_ok()
 {
-self.any_unifications = true;
+self.storage.any_unifications = true;
 };
 }
 (_, ty::ReVar(vid)) => {
@@ -477,7 +462,7 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 .unify_var_value(vid,RegionVariableValue::Known{value: a })
 .is_ok()
 {
-self.any_unifications = true;
+self.storage.any_unifications = true;
 };
 }
 (_, _) => {}
@@ -499,7 +484,7 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 return;
 }
 
-self.data.member_constraints.push(MemberConstraint{
+self.storage.data.member_constraints.push(MemberConstraint{
  key,
  definition_span,
  hidden_ty,
@@ -615,8 +600,8 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 
 fncombine_map(&mutself,t:CombineMapType) -> &mutCombineMap<'tcx>{
 match t {
-Glb => &mutself.glbs,
-Lub => &mutself.lubs,
+Glb => &mutself.storage.glbs,
+Lub => &mutself.storage.lubs,
 }
 }
 
@@ -669,11 +654,12 @@ impl<'tcx> RegionConstraintCollector<'_, 'tcx> {
 &self,
 value_count:usize,
 ) -> (Range<RegionVid>,Vec<RegionVariableOrigin>){
-let range = RegionVid::from(value_count)..RegionVid::from(self.unification_table.len());
+let range =
+RegionVid::from(value_count)..RegionVid::from(self.storage.unification_table.len());
 (
  range.clone(),
 (range.start.index()..range.end.index())
-.map(|index| self.var_infos[ty::RegionVid::from(index)].origin)
+.map(|index| self.storage.var_infos[ty::RegionVid::from(index)].origin)
 .collect(),
 )
 }