Uplift TypeError

compiler/rustc_hir_analysis/src/check/check.rs

@@ -15,6 +15,7 @@ use rustc_lint_defs::builtin::REPR_TRANSPARENT_EXTERNAL_PRIVATE_FIELDS;
 use rustc_middle::middle::resolve_bound_vars::ResolvedArg;
 use rustc_middle::middle::stability::EvalResult;
 use rustc_middle::span_bug;
+use rustc_middle::ty::error::TypeErrorToStringExt;
 use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::layout::{LayoutError, MAX_SIMD_LANES};
 use rustc_middle::ty::util::{Discr, InspectCoroutineFields, IntTypeExt};

compiler/rustc_hir_typeck/src/expr.rs

@@ -40,7 +40,7 @@ use rustc_infer::infer::InferOk;
 use rustc_infer::traits::query::NoSolution;
 use rustc_infer::traits::ObligationCause;
 use rustc_middle::ty::adjustment::{Adjust, Adjustment, AllowTwoPhase};
-use rustc_middle::ty::error::{ExpectedFound, TypeError::Sorts};
+use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::GenericArgsRef;
 use rustc_middle::ty::{self, AdtKind, Ty, TypeVisitableExt};
 use rustc_middle::{bug, span_bug};
@@ -682,7 +682,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             self.suggest_mismatched_types_on_tail(
                                 &mut err, expr, ty, e_ty, target_id,
                             );
-                            let error = Some(Sorts(ExpectedFound { expected: ty, found: e_ty }));
+                            let error =
+                                Some(TypeError::Sorts(ExpectedFound { expected: ty, found: e_ty }));
                             self.annotate_loop_expected_due_to_inference(err, expr, error);
                             if let Some(val) =
                                 self.err_ctxt().ty_kind_suggestion(self.param_env, ty)

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

@@ -71,6 +71,7 @@ use rustc_hir::lang_items::LangItem;
 use rustc_macros::extension;
 use rustc_middle::bug;
 use rustc_middle::dep_graph::DepContext;
+use rustc_middle::ty::error::TypeErrorToStringExt;
 use rustc_middle::ty::print::{with_forced_trimmed_paths, PrintError, PrintTraitRefExt as _};
 use rustc_middle::ty::relate::{self, RelateResult, TypeRelation};
 use rustc_middle::ty::Upcast;

compiler/rustc_infer/src/infer/error_reporting/note_and_explain.rs

@@ -21,13 +21,12 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         sp: Span,
         body_owner_def_id: DefId,
     ) {
-        use ty::error::TypeError::*;
         debug!("note_and_explain_type_err err={:?} cause={:?}", err, cause);
 
         let tcx = self.tcx;
 
         match err {
-            ArgumentSorts(values, _) | Sorts(values) => {
+            TypeError::ArgumentSorts(values, _) | TypeError::Sorts(values) => {
                 match (*values.expected.kind(), *values.found.kind()) {
                     (ty::Closure(..), ty::Closure(..)) => {
                         diag.note("no two closures, even if identical, have the same type");
@@ -483,7 +482,7 @@ impl<T> Trait<T> for X {
                     values.found.kind(),
                 );
             }
-            CyclicTy(ty) => {
+            TypeError::CyclicTy(ty) => {
                 // Watch out for various cases of cyclic types and try to explain.
                 if ty.is_closure() || ty.is_coroutine() || ty.is_coroutine_closure() {
                     diag.note(
@@ -494,7 +493,7 @@ impl<T> Trait<T> for X {
                     );
                 }
             }
-            TargetFeatureCast(def_id) => {
+            TypeError::TargetFeatureCast(def_id) => {
                 let target_spans = tcx.get_attrs(def_id, sym::target_feature).map(|attr| attr.span);
                 diag.note(
                     "functions with `#[target_feature]` can only be coerced to `unsafe` function pointers"

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

@@ -276,7 +276,7 @@ impl<'a, 'b, 'tcx> LeakCheck<'a, 'b, 'tcx> {
         other_region: ty::Region<'tcx>,
     ) -> TypeError<'tcx> {
         debug!("error: placeholder={:?}, other_region={:?}", placeholder, other_region);
-        TypeError::RegionsInsufficientlyPolymorphic(placeholder.bound.kind, other_region)
+        TypeError::RegionsInsufficientlyPolymorphic(placeholder.bound, other_region)
     }
 }
 

compiler/rustc_middle/src/traits/query.rs

@@ -7,7 +7,6 @@
 
 use crate::error::DropCheckOverflow;
 use crate::infer::canonical::{Canonical, QueryResponse};
-use crate::ty::error::TypeError;
 use crate::ty::GenericArg;
 use crate::ty::{self, Ty, TyCtxt};
 use rustc_macros::{HashStable, TypeFoldable, TypeVisitable};
@@ -91,12 +90,6 @@ pub type CanonicalTypeOpProvePredicateGoal<'tcx> =
 pub type CanonicalTypeOpNormalizeGoal<'tcx, T> =
     Canonical<'tcx, ty::ParamEnvAnd<'tcx, type_op::Normalize<T>>>;
 
-impl<'tcx> From<TypeError<'tcx>> for NoSolution {
-    fn from(_: TypeError<'tcx>) -> NoSolution {
-        NoSolution
-    }
-}
-
 #[derive(Clone, Debug, Default, HashStable, TypeFoldable, TypeVisitable)]
 pub struct DropckOutlivesResult<'tcx> {
     pub kinds: Vec<GenericArg<'tcx>>,

compiler/rustc_middle/src/ty/error.rs

@@ -1,89 +1,26 @@
 use crate::ty::print::{with_forced_trimmed_paths, FmtPrinter, PrettyPrinter};
-use crate::ty::{self, BoundRegionKind, Region, Ty, TyCtxt};
+use crate::ty::{self, Ty, TyCtxt};
+
 use rustc_errors::pluralize;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorOf, DefKind};
-use rustc_hir::def_id::DefId;
-use rustc_macros::{TypeFoldable, TypeVisitable};
-use rustc_span::symbol::Symbol;
-use rustc_target::spec::abi;
+use rustc_macros::extension;
+pub use rustc_type_ir::error::ExpectedFound;
+
 use std::borrow::Cow;
 use std::hash::{DefaultHasher, Hash, Hasher};
 use std::path::PathBuf;
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq, TypeFoldable, TypeVisitable)]
-pub struct ExpectedFound<T> {
-    pub expected: T,
-    pub found: T,
-}
-
-impl<T> ExpectedFound<T> {
-    pub fn new(a_is_expected: bool, a: T, b: T) -> Self {
-        if a_is_expected {
-            ExpectedFound { expected: a, found: b }
-        } else {
-            ExpectedFound { expected: b, found: a }
-        }
-    }
-}
-
-// Data structures used in type unification
-#[derive(Copy, Clone, Debug, TypeVisitable, PartialEq, Eq)]
-#[rustc_pass_by_value]
-pub enum TypeError<'tcx> {
-    Mismatch,
-    ConstnessMismatch(ExpectedFound<ty::BoundConstness>),
-    PolarityMismatch(ExpectedFound<ty::PredicatePolarity>),
-    SafetyMismatch(ExpectedFound<hir::Safety>),
-    AbiMismatch(ExpectedFound<abi::Abi>),
-    Mutability,
-    ArgumentMutability(usize),
-    TupleSize(ExpectedFound<usize>),
-    FixedArraySize(ExpectedFound<u64>),
-    ArgCount,
-    FieldMisMatch(Symbol, Symbol),
-
-    RegionsDoesNotOutlive(Region<'tcx>, Region<'tcx>),
-    RegionsInsufficientlyPolymorphic(BoundRegionKind, Region<'tcx>),
-    RegionsPlaceholderMismatch,
-
-    Sorts(ExpectedFound<Ty<'tcx>>),
-    ArgumentSorts(ExpectedFound<Ty<'tcx>>, usize),
-    Traits(ExpectedFound<DefId>),
-    VariadicMismatch(ExpectedFound<bool>),
-
-    /// Instantiating a type variable with the given type would have
-    /// created a cycle (because it appears somewhere within that
-    /// type).
-    CyclicTy(Ty<'tcx>),
-    CyclicConst(ty::Const<'tcx>),
-    ProjectionMismatched(ExpectedFound<DefId>),
-    ExistentialMismatch(ExpectedFound<&'tcx ty::List<ty::PolyExistentialPredicate<'tcx>>>),
-    ConstMismatch(ExpectedFound<ty::Const<'tcx>>),
-
-    IntrinsicCast,
-    /// Safe `#[target_feature]` functions are not assignable to safe function pointers.
-    TargetFeatureCast(DefId),
-}
-
-impl TypeError<'_> {
-    pub fn involves_regions(self) -> bool {
-        match self {
-            TypeError::RegionsDoesNotOutlive(_, _)
-            | TypeError::RegionsInsufficientlyPolymorphic(_, _)
-            | TypeError::RegionsPlaceholderMismatch => true,
-            _ => false,
-        }
-    }
-}
+pub type TypeError<'tcx> = rustc_type_ir::error::TypeError<TyCtxt<'tcx>>;
 
-/// Explains the source of a type err in a short, human readable way. This is meant to be placed
-/// in parentheses after some larger message. You should also invoke `note_and_explain_type_err()`
-/// afterwards to present additional details, particularly when it comes to lifetime-related
-/// errors.
+/// Explains the source of a type err in a short, human readable way.
+/// This is meant to be placed in parentheses after some larger message.
+/// You should also invoke `note_and_explain_type_err()` afterwards
+/// to present additional details, particularly when it comes to lifetime-
+/// related errors.
+#[extension(pub trait TypeErrorToStringExt<'tcx>)]
 impl<'tcx> TypeError<'tcx> {
-    pub fn to_string(self, tcx: TyCtxt<'tcx>) -> Cow<'static, str> {
-        use self::TypeError::*;
+    fn to_string(self, tcx: TyCtxt<'tcx>) -> Cow<'static, str> {
         fn report_maybe_different(expected: &str, found: &str) -> String {
             // A naive approach to making sure that we're not reporting silly errors such as:
             // (expected closure, found closure).
@@ -95,53 +32,56 @@ impl<'tcx> TypeError<'tcx> {
         }
 
         match self {
-            CyclicTy(_) => "cyclic type of infinite size".into(),
-            CyclicConst(_) => "encountered a self-referencing constant".into(),
-            Mismatch => "types differ".into(),
-            ConstnessMismatch(values) => {
+            TypeError::CyclicTy(_) => "cyclic type of infinite size".into(),
+            TypeError::CyclicConst(_) => "encountered a self-referencing constant".into(),
+            TypeError::Mismatch => "types differ".into(),
+            TypeError::ConstnessMismatch(values) => {
                 format!("expected {} bound, found {} bound", values.expected, values.found).into()
             }
-            PolarityMismatch(values) => {
+            TypeError::PolarityMismatch(values) => {
                 format!("expected {} polarity, found {} polarity", values.expected, values.found)
                     .into()
             }
-            SafetyMismatch(values) => {
+            TypeError::SafetyMismatch(values) => {
                 format!("expected {} fn, found {} fn", values.expected, values.found).into()
             }
-            AbiMismatch(values) => {
+            TypeError::AbiMismatch(values) => {
                 format!("expected {} fn, found {} fn", values.expected, values.found).into()
             }
-            ArgumentMutability(_) | Mutability => "types differ in mutability".into(),
-            TupleSize(values) => format!(
+            TypeError::ArgumentMutability(_) | TypeError::Mutability => {
+                "types differ in mutability".into()
+            }
+            TypeError::TupleSize(values) => format!(
                 "expected a tuple with {} element{}, found one with {} element{}",
                 values.expected,
                 pluralize!(values.expected),
                 values.found,
                 pluralize!(values.found)
             )
             .into(),
-            FixedArraySize(values) => format!(
+            TypeError::FixedArraySize(values) => format!(
                 "expected an array with a fixed size of {} element{}, found one with {} element{}",
                 values.expected,
                 pluralize!(values.expected),
                 values.found,
                 pluralize!(values.found)
             )
             .into(),
-            ArgCount => "incorrect number of function parameters".into(),
-            FieldMisMatch(adt, field) => format!("field type mismatch: {adt}.{field}").into(),
-            RegionsDoesNotOutlive(..) => "lifetime mismatch".into(),
+            TypeError::ArgCount => "incorrect number of function parameters".into(),
+            TypeError::RegionsDoesNotOutlive(..) => "lifetime mismatch".into(),
             // Actually naming the region here is a bit confusing because context is lacking
-            RegionsInsufficientlyPolymorphic(..) => {
+            TypeError::RegionsInsufficientlyPolymorphic(..) => {
+                "one type is more general than the other".into()
+            }
+            TypeError::RegionsPlaceholderMismatch => {
                 "one type is more general than the other".into()
             }
-            RegionsPlaceholderMismatch => "one type is more general than the other".into(),
-            ArgumentSorts(values, _) | Sorts(values) => {
+            TypeError::ArgumentSorts(values, _) | TypeError::Sorts(values) => {
                 let expected = values.expected.sort_string(tcx);
                 let found = values.found.sort_string(tcx);
                 report_maybe_different(&expected, &found).into()
             }
-            Traits(values) => {
+            TypeError::Traits(values) => {
                 let (mut expected, mut found) = with_forced_trimmed_paths!((
                     tcx.def_path_str(values.expected),
                     tcx.def_path_str(values.found),
@@ -153,59 +93,34 @@ impl<'tcx> TypeError<'tcx> {
                 report_maybe_different(&format!("trait `{expected}`"), &format!("trait `{found}`"))
                     .into()
             }
-            VariadicMismatch(ref values) => format!(
+            TypeError::VariadicMismatch(ref values) => format!(
                 "expected {} fn, found {} function",
                 if values.expected { "variadic" } else { "non-variadic" },
                 if values.found { "variadic" } else { "non-variadic" }
             )
             .into(),
-            ProjectionMismatched(ref values) => format!(
+            TypeError::ProjectionMismatched(ref values) => format!(
                 "expected `{}`, found `{}`",
                 tcx.def_path_str(values.expected),
                 tcx.def_path_str(values.found)
             )
             .into(),
-            ExistentialMismatch(ref values) => report_maybe_different(
+            TypeError::ExistentialMismatch(ref values) => report_maybe_different(
                 &format!("trait `{}`", values.expected),
                 &format!("trait `{}`", values.found),
             )
             .into(),
-            ConstMismatch(ref values) => {
+            TypeError::ConstMismatch(ref values) => {
                 format!("expected `{}`, found `{}`", values.expected, values.found).into()
             }
-            IntrinsicCast => "cannot coerce intrinsics to function pointers".into(),
-            TargetFeatureCast(_) => {
+            TypeError::IntrinsicCast => "cannot coerce intrinsics to function pointers".into(),
+            TypeError::TargetFeatureCast(_) => {
                 "cannot coerce functions with `#[target_feature]` to safe function pointers".into()
             }
         }
     }
 }
 
-impl<'tcx> TypeError<'tcx> {
-    pub fn must_include_note(self) -> bool {
-        use self::TypeError::*;
-        match self {
-            CyclicTy(_) | CyclicConst(_) | SafetyMismatch(_) | ConstnessMismatch(_)
-            | PolarityMismatch(_) | Mismatch | AbiMismatch(_) | FixedArraySize(_)
-            | ArgumentSorts(..) | Sorts(_) | VariadicMismatch(_) | TargetFeatureCast(_) => false,
-
-            Mutability
-            | ArgumentMutability(_)
-            | TupleSize(_)
-            | ArgCount
-            | FieldMisMatch(..)
-            | RegionsDoesNotOutlive(..)
-            | RegionsInsufficientlyPolymorphic(..)
-            | RegionsPlaceholderMismatch
-            | Traits(_)
-            | ProjectionMismatched(_)
-            | ExistentialMismatch(_)
-            | ConstMismatch(_)
-            | IntrinsicCast => true,
-        }
-    }
-}
-
 impl<'tcx> Ty<'tcx> {
     pub fn sort_string(self, tcx: TyCtxt<'tcx>) -> Cow<'static, str> {
         match *self.kind() {

compiler/rustc_middle/src/ty/mod.rs

@@ -313,38 +313,6 @@ impl Visibility {
     }
 }
 
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable, TyEncodable, TyDecodable)]
-pub enum BoundConstness {
-    /// `Type: Trait`
-    NotConst,
-    /// `Type: const Trait`
-    Const,
-    /// `Type: ~const Trait`
-    ///
-    /// Requires resolving to const only when we are in a const context.
-    ConstIfConst,
-}
-
-impl BoundConstness {
-    pub fn as_str(self) -> &'static str {
-        match self {
-            Self::NotConst => "",
-            Self::Const => "const",
-            Self::ConstIfConst => "~const",
-        }
-    }
-}
-
-impl fmt::Display for BoundConstness {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match self {
-            Self::NotConst => f.write_str("normal"),
-            Self::Const => f.write_str("const"),
-            Self::ConstIfConst => f.write_str("~const"),
-        }
-    }
-}
-
 #[derive(Clone, Debug, PartialEq, Eq, Copy, Hash, TyEncodable, TyDecodable, HashStable)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub struct ClosureSizeProfileData<'tcx> {