Auto merge of #127493 - compiler-errors:crate-level-import, r=lcnr

Move trait selection error reporting to its own top-level module

This effectively moves `rustc_trait_selection::traits::error_reporting` to `rustc_trait_selection::error_reporting::traits`. There are only a couple of actual changes to the code, like moving the `pretty_impl_header` fn out of the specialization module for privacy reasons.

This is quite pointless on its own, but having `error_reporting` as a top-level module in `rustc_trait_selection` is very important to make sure we have a meaningful file structure for when we move **type** error reporting (and region error reporting, with which it's incredibly entangled currently) into `rustc_trait_selection`. I've opened a tracking issue here: #127492

r? lcnr

Author: bors

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -34,9 +34,9 @@ use rustc_span::def_id::LocalDefId;
 use rustc_span::hygiene::DesugaringKind;
 use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::{BytePos, Span, Symbol};
+use rustc_trait_selection::error_reporting::traits::suggestions::TypeErrCtxtExt;
+use rustc_trait_selection::error_reporting::traits::FindExprBySpan;
 use rustc_trait_selection::infer::InferCtxtExt;
-use rustc_trait_selection::traits::error_reporting::suggestions::TypeErrCtxtExt;
-use rustc_trait_selection::traits::error_reporting::FindExprBySpan;
 use rustc_trait_selection::traits::{Obligation, ObligationCause, ObligationCtxt};
 use std::iter;
 use std::ops::ControlFlow;

compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs

@@ -17,7 +17,7 @@ use rustc_middle::ty::adjustment::PointerCoercion;
 use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt};
 use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{sym, DesugaringKind, Span};
-use rustc_trait_selection::traits::error_reporting::FindExprBySpan;
+use rustc_trait_selection::error_reporting::traits::FindExprBySpan;
 
 use crate::region_infer::{BlameConstraint, ExtraConstraintInfo};
 use crate::{

compiler/rustc_borrowck/src/diagnostics/mod.rs

@@ -27,8 +27,8 @@ use rustc_span::def_id::LocalDefId;
 use rustc_span::source_map::Spanned;
 use rustc_span::{symbol::sym, Span, Symbol, DUMMY_SP};
 use rustc_target::abi::{FieldIdx, VariantIdx};
+use rustc_trait_selection::error_reporting::traits::suggestions::TypeErrCtxtExt as _;
 use rustc_trait_selection::infer::InferCtxtExt;
-use rustc_trait_selection::traits::error_reporting::suggestions::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::{
     type_known_to_meet_bound_modulo_regions, FulfillmentErrorCode,
 };

compiler/rustc_borrowck/src/diagnostics/move_errors.rs

@@ -9,7 +9,7 @@ use rustc_middle::mir::*;
 use rustc_middle::ty::{self, Ty};
 use rustc_mir_dataflow::move_paths::{LookupResult, MovePathIndex};
 use rustc_span::{BytePos, ExpnKind, MacroKind, Span};
-use rustc_trait_selection::traits::error_reporting::FindExprBySpan;
+use rustc_trait_selection::error_reporting::traits::FindExprBySpan;
 
 use crate::diagnostics::CapturedMessageOpt;
 use crate::diagnostics::{DescribePlaceOpt, UseSpans};

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -16,9 +16,9 @@ use rustc_middle::{
 use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{sym, BytePos, DesugaringKind, Span};
 use rustc_target::abi::FieldIdx;
+use rustc_trait_selection::error_reporting::traits::suggestions::TypeErrCtxtExt;
 use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::traits;
-use rustc_trait_selection::traits::error_reporting::suggestions::TypeErrCtxtExt;
 
 use crate::diagnostics::BorrowedContentSource;
 use crate::util::FindAssignments;

compiler/rustc_borrowck/src/region_infer/opaque_types.rs

@@ -11,7 +11,7 @@ use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{self, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeFoldable};
 use rustc_middle::ty::{GenericArgKind, GenericArgs};
 use rustc_span::Span;
-use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
+use rustc_trait_selection::error_reporting::traits::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::ObligationCtxt;
 
 use crate::session_diagnostics::LifetimeMismatchOpaqueParam;

compiler/rustc_borrowck/src/type_check/free_region_relations.rs

@@ -11,8 +11,8 @@ use rustc_middle::traits::query::OutlivesBound;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::{self, RegionVid, Ty, TypeVisitableExt};
 use rustc_span::{ErrorGuaranteed, Span};
+use rustc_trait_selection::error_reporting::traits::TypeErrCtxtExt;
 use rustc_trait_selection::solve::deeply_normalize;
-use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt;
 use rustc_trait_selection::traits::query::type_op::{self, TypeOp};
 use std::rc::Rc;
 use type_op::TypeOpOutput;

compiler/rustc_const_eval/src/check_consts/check.rs

@@ -13,7 +13,7 @@ use rustc_middle::ty::{self, adjustment::PointerCoercion, Ty, TyCtxt};
 use rustc_middle::ty::{Instance, InstanceKind, TypeVisitableExt};
 use rustc_mir_dataflow::Analysis;
 use rustc_span::{sym, Span, Symbol, DUMMY_SP};
-use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
+use rustc_trait_selection::error_reporting::traits::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::{self, ObligationCauseCode, ObligationCtxt};
 use rustc_type_ir::visit::{TypeSuperVisitable, TypeVisitor};
 

compiler/rustc_hir_analysis/src/check/check.rs

@@ -25,9 +25,9 @@ use rustc_middle::ty::{
 };
 use rustc_session::lint::builtin::{UNINHABITED_STATIC, UNSUPPORTED_CALLING_CONVENTIONS};
 use rustc_target::abi::FieldIdx;
+use rustc_trait_selection::error_reporting::traits::on_unimplemented::OnUnimplementedDirective;
+use rustc_trait_selection::error_reporting::traits::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits;
-use rustc_trait_selection::traits::error_reporting::on_unimplemented::OnUnimplementedDirective;
-use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
 use rustc_type_ir::fold::TypeFoldable;
 

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -21,9 +21,9 @@ use rustc_middle::ty::{
 use rustc_middle::ty::{GenericParamDefKind, TyCtxt};
 use rustc_middle::{bug, span_bug};
 use rustc_span::Span;
+use rustc_trait_selection::error_reporting::traits::TypeErrCtxtExt;
 use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::regions::InferCtxtRegionExt;
-use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt;
 use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
 use rustc_trait_selection::traits::{
     self, FulfillmentError, ObligationCause, ObligationCauseCode, ObligationCtxt, Reveal,