Reduce visibilities some more.

It helps people reading the code understand how widely things are used.

compiler/rustc_infer/src/infer/mod.rs

@@ -14,7 +14,8 @@
     GenericKind, RegionConstraintCollector, RegionConstraintStorage, VarInfos, VerifyBound,
 };
 pub use relate::StructurallyRelateAliases;
-pub use relate::combine::{CombineFields, PredicateEmittingRelation};
+use relate::combine::CombineFields;
+pub use relate::combine::PredicateEmittingRelation;
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::{FxHashSet, FxIndexMap};
 use rustc_data_structures::sync::Lrc;
@@ -75,7 +76,7 @@ pub struct InferOk<'tcx, T> {
 }
 pub type InferResult<'tcx, T> = Result<InferOk<'tcx, T>, TypeError<'tcx>>;
 
-pub type FixupResult<T> = Result<T, FixupError>; // "fixup result"
+pub(crate) type FixupResult<T> = Result<T, FixupError>; // "fixup result"
 
 pub(crate) type UnificationTable<'a, 'tcx, T> = ut::UnificationTable<
     ut::InPlace<T, &'a mut ut::UnificationStorage<T>, &'a mut InferCtxtUndoLogs<'tcx>>,
@@ -200,7 +201,7 @@ fn type_variables(&mut self) -> type_variable::TypeVariableTable<'_, 'tcx> {
     }
 
     #[inline]
-    pub fn opaque_types(&mut self) -> opaque_types::OpaqueTypeTable<'_, 'tcx> {
+    fn opaque_types(&mut self) -> opaque_types::OpaqueTypeTable<'_, 'tcx> {
         self.opaque_type_storage.with_log(&mut self.undo_log)
     }
 
@@ -1351,7 +1352,7 @@ fn replace_const(&mut self, bv: ty::BoundVar) -> ty::Const<'tcx> {
     }
 
     /// See the [`region_constraints::RegionConstraintCollector::verify_generic_bound`] method.
-    pub fn verify_generic_bound(
+    pub(crate) fn verify_generic_bound(
         &self,
         origin: SubregionOrigin<'tcx>,
         kind: GenericKind<'tcx>,

compiler/rustc_infer/src/infer/opaque_types/table.rs

@@ -46,7 +46,7 @@ fn drop(&mut self) {
     }
 }
 
-pub struct OpaqueTypeTable<'a, 'tcx> {
+pub(crate) struct OpaqueTypeTable<'a, 'tcx> {
     storage: &'a mut OpaqueTypeStorage<'tcx>,
 
     undo_log: &'a mut InferCtxtUndoLogs<'tcx>,

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

@@ -14,7 +14,7 @@
 pub mod for_liveness;
 pub mod obligations;
 pub mod test_type_match;
-pub mod verify;
+pub(crate) mod verify;
 
 #[instrument(level = "debug", skip(param_env), ret)]
 pub fn explicit_outlives_bounds<'tcx>(

compiler/rustc_infer/src/infer/outlives/verify.rs

@@ -15,7 +15,7 @@
 /// via a "delegate" of type `D` -- this is usually the `infcx`, which
 /// accrues them into the `region_obligations` code, but for NLL we
 /// use something else.
-pub struct VerifyBoundCx<'cx, 'tcx> {
+pub(crate) struct VerifyBoundCx<'cx, 'tcx> {
     tcx: TyCtxt<'tcx>,
     region_bound_pairs: &'cx RegionBoundPairs<'tcx>,
     /// During borrowck, if there are no outlives bounds on a generic
@@ -28,7 +28,7 @@ pub struct VerifyBoundCx<'cx, 'tcx> {
 }
 
 impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> {
-    pub fn new(
+    pub(crate) fn new(
         tcx: TyCtxt<'tcx>,
         region_bound_pairs: &'cx RegionBoundPairs<'tcx>,
         implicit_region_bound: Option<ty::Region<'tcx>>,
@@ -38,7 +38,7 @@ pub fn new(
     }
 
     #[instrument(level = "debug", skip(self))]
-    pub fn param_or_placeholder_bound(&self, ty: Ty<'tcx>) -> VerifyBound<'tcx> {
+    pub(crate) fn param_or_placeholder_bound(&self, ty: Ty<'tcx>) -> VerifyBound<'tcx> {
         // Start with anything like `T: 'a` we can scrape from the
         // environment. If the environment contains something like
         // `for<'a> T: 'a`, then we know that `T` outlives everything.
@@ -92,7 +92,7 @@ pub fn param_or_placeholder_bound(&self, ty: Ty<'tcx>) -> VerifyBound<'tcx> {
     /// the clause from the environment only applies if `'0 = 'a`,
     /// which we don't know yet. But we would still include `'b` in
     /// this list.
-    pub fn approx_declared_bounds_from_env(
+    pub(crate) fn approx_declared_bounds_from_env(
         &self,
         alias_ty: ty::AliasTy<'tcx>,
     ) -> Vec<ty::PolyTypeOutlivesPredicate<'tcx>> {
@@ -101,7 +101,7 @@ pub fn approx_declared_bounds_from_env(
     }
 
     #[instrument(level = "debug", skip(self))]
-    pub fn alias_bound(&self, alias_ty: ty::AliasTy<'tcx>) -> VerifyBound<'tcx> {
+    pub(crate) fn alias_bound(&self, alias_ty: ty::AliasTy<'tcx>) -> VerifyBound<'tcx> {
         let alias_ty_as_ty = alias_ty.to_ty(self.tcx);
 
         // Search the env for where clauses like `P: 'a`.
@@ -285,7 +285,7 @@ fn declared_generic_bounds_from_env_for_erased_ty(
     ///
     /// This is for simplicity, and because we are not really smart
     /// enough to cope with such bounds anywhere.
-    pub fn declared_bounds_from_definition(
+    pub(crate) fn declared_bounds_from_definition(
         &self,
         alias_ty: ty::AliasTy<'tcx>,
     ) -> impl Iterator<Item = ty::Region<'tcx>> {

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

@@ -304,7 +304,7 @@ pub struct RegionVariableInfo {
     pub universe: ty::UniverseIndex,
 }
 
-pub struct RegionSnapshot {
+pub(crate) struct RegionSnapshot {
     any_unifications: bool,
 }
 

compiler/rustc_infer/src/infer/relate/combine.rs

@@ -33,7 +33,7 @@
 use crate::traits::{Obligation, PredicateObligation};
 
 #[derive(Clone)]
-pub struct CombineFields<'infcx, 'tcx> {
+pub(crate) struct CombineFields<'infcx, 'tcx> {
     pub infcx: &'infcx InferCtxt<'tcx>,
     // Immutable fields
     pub trace: TypeTrace<'tcx>,
@@ -47,7 +47,7 @@ pub struct CombineFields<'infcx, 'tcx> {
 }
 
 impl<'infcx, 'tcx> CombineFields<'infcx, 'tcx> {
-    pub fn new(
+    pub(crate) fn new(
         infcx: &'infcx InferCtxt<'tcx>,
         trace: TypeTrace<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
@@ -283,22 +283,22 @@ fn unify_effect_variable(&self, vid: ty::EffectVid, val: ty::Const<'tcx>) -> ty:
 }
 
 impl<'infcx, 'tcx> CombineFields<'infcx, 'tcx> {
-    pub fn tcx(&self) -> TyCtxt<'tcx> {
+    pub(crate) fn tcx(&self) -> TyCtxt<'tcx> {
         self.infcx.tcx
     }
 
-    pub fn equate<'a>(
+    pub(crate) fn equate<'a>(
         &'a mut self,
         structurally_relate_aliases: StructurallyRelateAliases,
     ) -> TypeRelating<'a, 'infcx, 'tcx> {
         TypeRelating::new(self, structurally_relate_aliases, ty::Invariant)
     }
 
-    pub fn sub<'a>(&'a mut self) -> TypeRelating<'a, 'infcx, 'tcx> {
+    pub(crate) fn sub<'a>(&'a mut self) -> TypeRelating<'a, 'infcx, 'tcx> {
         TypeRelating::new(self, StructurallyRelateAliases::No, ty::Covariant)
     }
 
-    pub fn sup<'a>(&'a mut self) -> TypeRelating<'a, 'infcx, 'tcx> {
+    pub(crate) fn sup<'a>(&'a mut self) -> TypeRelating<'a, 'infcx, 'tcx> {
         TypeRelating::new(self, StructurallyRelateAliases::No, ty::Contravariant)
     }
 
@@ -310,14 +310,14 @@ pub(crate) fn glb<'a>(&'a mut self) -> LatticeOp<'a, 'infcx, 'tcx> {
         LatticeOp::new(self, LatticeOpKind::Glb)
     }
 
-    pub fn register_obligations(
+    pub(crate) fn register_obligations(
         &mut self,
         obligations: impl IntoIterator<Item = Goal<'tcx, ty::Predicate<'tcx>>>,
     ) {
         self.goals.extend(obligations);
     }
 
-    pub fn register_predicates(
+    pub(crate) fn register_predicates(
         &mut self,
         obligations: impl IntoIterator<Item: Upcast<TyCtxt<'tcx>, ty::Predicate<'tcx>>>,
     ) {

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

@@ -5,7 +5,7 @@
 pub use rustc_middle::ty::relate::RelateResult;
 pub use rustc_next_trait_solver::relate::*;
 
-pub use self::combine::{CombineFields, PredicateEmittingRelation};
+pub use self::combine::PredicateEmittingRelation;
 
 #[allow(hidden_glob_reexports)]
 pub(super) mod combine;

compiler/rustc_infer/src/infer/relate/type_relating.rs

@@ -13,7 +13,7 @@
 use crate::infer::{DefineOpaqueTypes, InferCtxt, SubregionOrigin};
 
 /// Enforce that `a` is equal to or a subtype of `b`.
-pub struct TypeRelating<'combine, 'a, 'tcx> {
+pub(crate) struct TypeRelating<'combine, 'a, 'tcx> {
     // Immutable except for the `InferCtxt` and the
     // resulting nested `goals`.
     fields: &'combine mut CombineFields<'a, 'tcx>,
@@ -49,7 +49,7 @@ pub struct TypeRelating<'combine, 'a, 'tcx> {
 }
 
 impl<'combine, 'infcx, 'tcx> TypeRelating<'combine, 'infcx, 'tcx> {
-    pub fn new(
+    pub(crate) fn new(
         f: &'combine mut CombineFields<'infcx, 'tcx>,
         structurally_relate_aliases: StructurallyRelateAliases,
         ambient_variance: ty::Variance,

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

@@ -5,7 +5,7 @@
 use super::InferCtxt;
 use super::region_constraints::RegionSnapshot;
 
-mod fudge;
+pub(crate) mod fudge;
 pub(crate) mod undo_log;
 
 use undo_log::{Snapshot, UndoLog};