Move folding & visiting traits to ir submodules

compiler/rustc_middle/src/ty/fold.rs

@@ -48,6 +48,11 @@ use rustc_hir::def_id::DefId;
 
 use std::collections::BTreeMap;
 
+pub use ir::{FallibleTypeFolder, TypeFoldable, TypeFolder, TypeSuperFoldable};
+
+pub mod ir {
+    use crate::ty::{self, ir::TypeVisitable, Binder, Ty, TyCtxt};
+
     /// This trait is implemented for every type that can be folded,
     /// providing the skeleton of the traversal.
     ///
@@ -64,7 +69,10 @@ pub trait TypeFoldable<'tcx>: TypeVisitable<'tcx> {
         /// calls a folder method specifically for that type (such as
         /// `F::try_fold_ty`). This is where control transfers from `TypeFoldable`
         /// to `TypeFolder`.
-    fn try_fold_with<F: FallibleTypeFolder<'tcx>>(self, folder: &mut F) -> Result<Self, F::Error>;
+        fn try_fold_with<F: FallibleTypeFolder<'tcx>>(
+            self,
+            folder: &mut F,
+        ) -> Result<Self, F::Error>;
 
         /// A convenient alternative to `try_fold_with` for use with infallible
         /// folders. Do not override this method, to ensure coherence with
@@ -154,7 +162,10 @@ pub trait FallibleTypeFolder<'tcx>: Sized {
             t.try_super_fold_with(self)
         }
 
-    fn try_fold_region(&mut self, r: ty::Region<'tcx>) -> Result<ty::Region<'tcx>, Self::Error> {
+        fn try_fold_region(
+            &mut self,
+            r: ty::Region<'tcx>,
+        ) -> Result<ty::Region<'tcx>, Self::Error> {
             r.try_super_fold_with(self)
         }
 
@@ -205,6 +216,7 @@ where
             Ok(self.fold_predicate(p))
         }
     }
+}
 
 ///////////////////////////////////////////////////////////////////////////
 // Some sample folders

compiler/rustc_middle/src/ty/mod.rs

@@ -146,6 +146,10 @@ mod structural_impls;
 mod sty;
 mod typeck_results;
 
+pub mod ir {
+    pub use super::{fold::ir::*, visit::ir::*};
+}
+
 // Data types
 
 pub type RegisteredTools = FxHashSet<Ident>;

compiler/rustc_middle/src/ty/visit.rs

@@ -39,13 +39,22 @@
 //! - u.visit_with(visitor)
 //! ```
 use crate::ty::{self, flags::FlagComputation, Binder, Ty, TyCtxt, TypeFlags};
-use rustc_errors::ErrorGuaranteed;
 
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sso::SsoHashSet;
+use std::ops::ControlFlow;
+
+pub use ir::{TypeSuperVisitable, TypeVisitable, TypeVisitor};
+
+pub mod ir {
+    use crate::ty::{self, Binder, Ty, TypeFlags};
+    use rustc_errors::ErrorGuaranteed;
+
     use std::fmt;
     use std::ops::ControlFlow;
 
+    use super::{FoundFlags, HasEscapingVarsVisitor, HasTypeFlagsVisitor};
+
     /// This trait is implemented for every type that can be visited,
     /// providing the skeleton of the traversal.
     ///
@@ -89,8 +98,8 @@ pub trait TypeVisitable<'tcx>: fmt::Debug + Clone {
         }
 
         fn has_type_flags(&self, flags: TypeFlags) -> bool {
-        let res =
-            self.visit_with(&mut HasTypeFlagsVisitor { flags }).break_value() == Some(FoundFlags);
+            let res = self.visit_with(&mut HasTypeFlagsVisitor { flags }).break_value()
+                == Some(FoundFlags);
             trace!(?self, ?flags, ?res, "has_type_flags");
             res
         }
@@ -108,7 +117,8 @@ pub trait TypeVisitable<'tcx>: fmt::Debug + Clone {
         }
         fn error_reported(&self) -> Result<(), ErrorGuaranteed> {
             if self.references_error() {
-            if let Some(reported) = ty::tls::with(|tcx| tcx.sess.is_compilation_going_to_fail()) {
+                if let Some(reported) = ty::tls::with(|tcx| tcx.sess.is_compilation_going_to_fail())
+                {
                     Err(reported)
                 } else {
                     bug!("expect tcx.sess.is_compilation_going_to_fail return `Some`");
@@ -192,7 +202,10 @@ pub trait TypeSuperVisitable<'tcx>: TypeVisitable<'tcx> {
         /// For example, in `MyVisitor::visit_ty(ty)`, it is valid to call
         /// `ty.super_visit_with(self)`, but any other visiting should be done
         /// with `xyz.visit_with(self)`.
-    fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> ControlFlow<V::BreakTy>;
+        fn super_visit_with<V: TypeVisitor<'tcx>>(
+            &self,
+            visitor: &mut V,
+        ) -> ControlFlow<V::BreakTy>;
     }
 
     /// This trait is implemented for every visiting traversal. There is a visit
@@ -224,6 +237,7 @@ pub trait TypeVisitor<'tcx>: Sized {
             p.super_visit_with(self)
         }
     }
+}
 
 ///////////////////////////////////////////////////////////////////////////
 // Region folder