Split UserTypeAnnotation to have a kind

compiler/rustc_borrowck/src/type_check/canonical.rs

@@ -275,7 +275,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         user_ty: ty::UserType<'tcx>,
         span: Span,
     ) {
-        let ty::UserType::Ty(user_ty) = user_ty else { bug!() };
+        let ty::UserTypeKind::Ty(user_ty) = user_ty.kind else { bug!() };
 
         // A fast path for a common case with closure input/output types.
         if let ty::Infer(_) = user_ty.kind() {

compiler/rustc_borrowck/src/type_check/input_output.rs

@@ -110,7 +110,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         ) {
             self.ascribe_user_type_skip_wf(
                 arg_decl.ty,
-                ty::UserType::Ty(user_ty),
+                ty::UserType::new(ty::UserTypeKind::Ty(user_ty)),
                 arg_decl.source_info.span,
             );
         }
@@ -119,7 +119,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         let output_decl = &body.local_decls[RETURN_PLACE];
         self.ascribe_user_type_skip_wf(
             output_decl.ty,
-            ty::UserType::Ty(user_provided_sig.output()),
+            ty::UserType::new(ty::UserTypeKind::Ty(user_provided_sig.output())),
             output_decl.source_info.span,
         );
     }

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -31,7 +31,7 @@ use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{
     self, Binder, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations, CoroutineArgsExt,
     Dynamic, GenericArgsRef, OpaqueHiddenType, OpaqueTypeKey, RegionVid, Ty, TyCtxt, UserArgs,
-    UserType, UserTypeAnnotationIndex,
+    UserTypeAnnotationIndex,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_mir_dataflow::ResultsCursor;
@@ -370,7 +370,10 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
                 } else {
                     self.cx.ascribe_user_type(
                         constant.const_.ty(),
-                        UserType::TypeOf(uv.def, UserArgs { args: uv.args, user_self_ty: None }),
+                        ty::UserType::new(ty::UserTypeKind::TypeOf(uv.def, UserArgs {
+                            args: uv.args,
+                            user_self_ty: None,
+                        })),
                         locations.span(self.cx.body),
                     );
                 }
@@ -991,9 +994,10 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         for user_annotation in self.user_type_annotations {
             let CanonicalUserTypeAnnotation { span, ref user_ty, inferred_ty } = *user_annotation;
             let annotation = self.instantiate_canonical(span, user_ty);
-            if let ty::UserType::TypeOf(def, args) = annotation
+            if let ty::UserTypeKind::TypeOf(def, args) = annotation.kind
                 && let DefKind::InlineConst = tcx.def_kind(def)
             {
+                // TODO:
                 self.check_inline_const(inferred_ty, def.expect_local(), args, span);
             } else {
                 self.ascribe_user_type(inferred_ty, annotation, span);

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -25,7 +25,7 @@ use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::visit::{TypeVisitable, TypeVisitableExt};
 use rustc_middle::ty::{
     self, AdtKind, CanonicalUserType, GenericArgKind, GenericArgsRef, GenericParamDefKind,
-    IsIdentity, Ty, TyCtxt, UserArgs, UserSelfTy, UserType,
+    IsIdentity, Ty, TyCtxt, UserArgs, UserSelfTy,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_session::lint;
@@ -216,11 +216,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         debug!("fcx {}", self.tag());
 
         if Self::can_contain_user_lifetime_bounds((args, user_self_ty)) {
-            let canonicalized =
+            let canonicalized = self.canonicalize_user_type_annotation(ty::UserType::new(
-                self.canonicalize_user_type_annotation(UserType::TypeOf(def_id, UserArgs {
+                ty::UserTypeKind::TypeOf(def_id, UserArgs { args, user_self_ty }),
-                    args,
+            ));
-                    user_self_ty,
-                }));
             debug!(?canonicalized);
             self.write_user_type_annotation(hir_id, canonicalized);
         }
@@ -468,7 +466,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         debug!(?ty);
 
         if Self::can_contain_user_lifetime_bounds(ty.raw) {
-            let c_ty = self.canonicalize_response(UserType::Ty(ty.raw));
+            let c_ty = self.canonicalize_response(ty::UserType::new(ty::UserTypeKind::Ty(ty.raw)));
             debug!(?c_ty);
             self.typeck_results.borrow_mut().user_provided_types_mut().insert(hir_ty.hir_id, c_ty);
         }

compiler/rustc_hir_typeck/src/gather_locals.rs

@@ -2,7 +2,7 @@ use rustc_hir as hir;
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{HirId, PatKind};
 use rustc_infer::traits::ObligationCauseCode;
-use rustc_middle::ty::{Ty, UserType};
+use rustc_middle::ty::{self, Ty};
 use rustc_span::Span;
 use rustc_span::def_id::LocalDefId;
 use tracing::debug;
@@ -92,7 +92,9 @@ impl<'a, 'tcx> GatherLocalsVisitor<'a, 'tcx> {
             Some(ref ty) => {
                 let o_ty = self.fcx.lower_ty(ty);
 
-                let c_ty = self.fcx.infcx.canonicalize_user_type_annotation(UserType::Ty(o_ty.raw));
+                let c_ty = self.fcx.infcx.canonicalize_user_type_annotation(ty::UserType::new(
+                    ty::UserTypeKind::Ty(o_ty.raw),
+                ));
                 debug!("visit_local: ty.hir_id={:?} o_ty={:?} c_ty={:?}", ty.hir_id, o_ty, c_ty);
                 self.fcx
                     .typeck_results

compiler/rustc_hir_typeck/src/method/confirm.rs

@@ -17,7 +17,6 @@ use rustc_middle::ty::adjustment::{
 use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::{
     self, GenericArgs, GenericArgsRef, GenericParamDefKind, Ty, TyCtxt, TypeVisitableExt, UserArgs,
-    UserType,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::{DUMMY_SP, Span};
@@ -491,9 +490,8 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
                     user_self_ty: None, // not relevant here
                 };
 
-                self.fcx.canonicalize_user_type_annotation(UserType::TypeOf(
+                self.fcx.canonicalize_user_type_annotation(ty::UserType::new(
-                    pick.item.def_id,
+                    ty::UserTypeKind::TypeOf(pick.item.def_id, user_args),
-                    user_args,
                 ))
             });
 

compiler/rustc_hir_typeck/src/writeback.rs

@@ -476,7 +476,7 @@ impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> {
             for (local_id, c_ty) in sorted_user_provided_types {
                 let hir_id = HirId { owner: common_hir_owner, local_id };
 
-                if let ty::UserType::TypeOf(_, user_args) = c_ty.value {
+                if let ty::UserTypeKind::TypeOf(_, user_args) = c_ty.value.kind {
                     // This is a unit-testing mechanism.
                     let span = self.tcx().hir().span(hir_id);
                     // We need to buffer the errors in order to guarantee a consistent

compiler/rustc_middle/src/ty/mod.rs

@@ -95,7 +95,7 @@ pub use self::sty::{
 pub use self::trait_def::TraitDef;
 pub use self::typeck_results::{
     CanonicalUserType, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations, IsIdentity,
-    TypeckResults, UserType, UserTypeAnnotationIndex,
+    TypeckResults, UserType, UserTypeAnnotationIndex, UserTypeKind,
 };
 pub use self::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor};
 use crate::error::{OpaqueHiddenTypeMismatch, TypeMismatchReason};

compiler/rustc_middle/src/ty/typeck_results.rs

@@ -700,12 +700,24 @@ pub struct CanonicalUserTypeAnnotation<'tcx> {
 /// Canonical user type annotation.
 pub type CanonicalUserType<'tcx> = Canonical<'tcx, UserType<'tcx>>;
 
+#[derive(Copy, Clone, Debug, PartialEq, TyEncodable, TyDecodable)]
+#[derive(Eq, Hash, HashStable, TypeFoldable, TypeVisitable)]
+pub struct UserType<'tcx> {
+    pub kind: UserTypeKind<'tcx>,
+}
+
+impl<'tcx> UserType<'tcx> {
+    pub fn new(kind: UserTypeKind<'tcx>) -> UserType<'tcx> {
+        UserType { kind }
+    }
+}
+
 /// A user-given type annotation attached to a constant. These arise
 /// from constants that are named via paths, like `Foo::<A>::new` and
 /// so forth.
 #[derive(Copy, Clone, Debug, PartialEq, TyEncodable, TyDecodable)]
 #[derive(Eq, Hash, HashStable, TypeFoldable, TypeVisitable)]
-pub enum UserType<'tcx> {
+pub enum UserTypeKind<'tcx> {
     Ty(Ty<'tcx>),
 
     /// The canonical type is the result of `type_of(def_id)` with the
@@ -721,9 +733,11 @@ impl<'tcx> IsIdentity for CanonicalUserType<'tcx> {
     /// Returns `true` if this represents the generic parameters of the form `[?0, ?1, ?2]`,
     /// i.e., each thing is mapped to a canonical variable with the same index.
     fn is_identity(&self) -> bool {
-        match self.value {
+        // TODO:
-            UserType::Ty(_) => false,
+
-            UserType::TypeOf(_, user_args) => {
+        match self.value.kind {
+            UserTypeKind::Ty(_) => false,
+            UserTypeKind::TypeOf(_, user_args) => {
                 if user_args.user_self_ty.is_some() {
                     return false;
                 }
@@ -764,6 +778,14 @@ impl<'tcx> IsIdentity for CanonicalUserType<'tcx> {
 }
 
 impl<'tcx> std::fmt::Display for UserType<'tcx> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        // TODO:
+
+        self.kind.fmt(f)
+    }
+}
+
+impl<'tcx> std::fmt::Display for UserTypeKind<'tcx> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             Self::Ty(arg0) => {

compiler/rustc_mir_build/src/build/matches/match_pair.rs

@@ -176,9 +176,8 @@ impl<'pat, 'tcx> MatchPairTree<'pat, 'tcx> {
                         ty: cx.infcx.next_ty_var(span),
                     })
                     .args;
-                    let user_ty = cx.infcx.canonicalize_user_type_annotation(ty::UserType::TypeOf(
+                    let user_ty = cx.infcx.canonicalize_user_type_annotation(ty::UserType::new(
-                        def_id,
+                        ty::UserTypeKind::TypeOf(def_id, ty::UserArgs { args, user_self_ty: None }),
-                        ty::UserArgs { args, user_self_ty: None },
                     ));
                     let annotation = ty::CanonicalUserTypeAnnotation {
                         inferred_ty: pattern.ty,

compiler/rustc_mir_build/src/thir/cx/expr.rs

@@ -15,7 +15,6 @@ use rustc_middle::ty::adjustment::{
 };
 use rustc_middle::ty::{
     self, AdtKind, GenericArgs, InlineConstArgs, InlineConstArgsParts, ScalarInt, Ty, UpvarArgs,
-    UserType,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::{Span, sym};
@@ -443,7 +442,9 @@ impl<'tcx> Cx<'tcx> {
                         let user_provided_types = self.typeck_results().user_provided_types();
                         let user_ty =
                             user_provided_types.get(fun.hir_id).copied().map(|mut u_ty| {
-                                if let UserType::TypeOf(ref mut did, _) = &mut u_ty.value {
+                                if let ty::UserTypeKind::TypeOf(ref mut did, _) =
+                                    &mut u_ty.value.kind
+                                {
                                     *did = adt_def.did();
                                 }
                                 Box::new(u_ty)

compiler/rustc_mir_build/src/thir/util.rs

@@ -1,6 +1,6 @@
 use rustc_hir as hir;
 use rustc_middle::bug;
-use rustc_middle::ty::{self, CanonicalUserType, TyCtxt, UserType};
+use rustc_middle::ty::{self, CanonicalUserType, TyCtxt};
 use tracing::debug;
 
 pub(crate) trait UserAnnotatedTyHelpers<'tcx> {
@@ -21,7 +21,7 @@ pub(crate) trait UserAnnotatedTyHelpers<'tcx> {
         let ty = self.typeck_results().node_type(hir_id);
         match ty.kind() {
             ty::Adt(adt_def, ..) => {
-                if let UserType::TypeOf(ref mut did, _) = &mut user_ty.value {
+                if let ty::UserTypeKind::TypeOf(ref mut did, _) = &mut user_ty.value.kind {
                     *did = adt_def.did();
                 }
                 Some(user_ty)

compiler/rustc_trait_selection/src/traits/query/type_op/ascribe_user_type.rs

@@ -3,7 +3,7 @@ use rustc_infer::traits::Obligation;
 use rustc_middle::traits::query::NoSolution;
 pub use rustc_middle::traits::query::type_op::AscribeUserType;
 use rustc_middle::traits::{ObligationCause, ObligationCauseCode};
-use rustc_middle::ty::{self, ParamEnvAnd, Ty, TyCtxt, UserArgs, UserSelfTy, UserType};
+use rustc_middle::ty::{self, ParamEnvAnd, Ty, TyCtxt, UserArgs, UserSelfTy, UserTypeKind};
 use rustc_span::{DUMMY_SP, Span};
 use tracing::{debug, instrument};
 
@@ -46,9 +46,9 @@ pub fn type_op_ascribe_user_type_with_span<'tcx>(
     let (param_env, AscribeUserType { mir_ty, user_ty }) = key.into_parts();
     debug!("type_op_ascribe_user_type: mir_ty={:?} user_ty={:?}", mir_ty, user_ty);
     let span = span.unwrap_or(DUMMY_SP);
-    match user_ty {
+    match user_ty.kind {
-        UserType::Ty(user_ty) => relate_mir_and_user_ty(ocx, param_env, span, mir_ty, user_ty)?,
+        UserTypeKind::Ty(user_ty) => relate_mir_and_user_ty(ocx, param_env, span, mir_ty, user_ty)?,
-        UserType::TypeOf(def_id, user_args) => {
+        UserTypeKind::TypeOf(def_id, user_args) => {
             relate_mir_and_user_args(ocx, param_env, span, mir_ty, def_id, user_args)?
         }
     };