Auto merge of #83188 - petrochenkov:field, r=lcnr

ast/hir: Rename field-related structures

I always forget what `ast::Field` and `ast::StructField` mean despite working with AST for long time, so this PR changes the naming to less confusing and more consistent.

- `StructField` -> `FieldDef` ("field definition")
- `Field` -> `ExprField` ("expression field", not "field expression")
- `FieldPat` -> `PatField` ("pattern field", not "field pattern")

Various visiting and other methods working with the fields are renamed correspondingly too.

The second commit reduces the size of `ExprKind` by boxing fields of `ExprKind::Struct` in preparation for https://github.com/rust-lang/rust/pull/80080.

compiler/rustc_typeck/src/check/expr.rs

@@ -1158,7 +1158,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expr: &hir::Expr<'_>,
         expected: Expectation<'tcx>,
         qpath: &QPath<'_>,
-        fields: &'tcx [hir::Field<'tcx>],
+        fields: &'tcx [hir::ExprField<'tcx>],
         base_expr: &'tcx Option<&'tcx hir::Expr<'tcx>>,
     ) -> Ty<'tcx> {
         // Find the relevant variant
@@ -1231,7 +1231,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expr_id: hir::HirId,
         span: Span,
         variant: &'tcx ty::VariantDef,
-        ast_fields: &'tcx [hir::Field<'tcx>],
+        ast_fields: &'tcx [hir::ExprField<'tcx>],
         check_completeness: bool,
     ) -> bool {
         let tcx = self.tcx;
@@ -1320,7 +1320,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
     fn check_struct_fields_on_error(
         &self,
-        fields: &'tcx [hir::Field<'tcx>],
+        fields: &'tcx [hir::ExprField<'tcx>],
         base_expr: &'tcx Option<&'tcx hir::Expr<'tcx>>,
     ) {
         for field in fields {
@@ -1411,8 +1411,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         ty: Ty<'tcx>,
         variant: &'tcx ty::VariantDef,
-        field: &hir::Field<'_>,
-        skip_fields: &[hir::Field<'_>],
+        field: &hir::ExprField<'_>,
+        skip_fields: &[hir::ExprField<'_>],
         kind_name: &str,
         ty_span: Span,
     ) {

compiler/rustc_typeck/src/check/pat.rs

@@ -680,7 +680,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         pat: &'tcx Pat<'tcx>,
         qpath: &hir::QPath<'_>,
-        fields: &'tcx [hir::FieldPat<'tcx>],
+        fields: &'tcx [hir::PatField<'tcx>],
         etc: bool,
         expected: Ty<'tcx>,
         def_bm: BindingMode,
@@ -1151,7 +1151,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         adt_ty: Ty<'tcx>,
         pat: &'tcx Pat<'tcx>,
         variant: &'tcx ty::VariantDef,
-        fields: &'tcx [hir::FieldPat<'tcx>],
+        fields: &'tcx [hir::PatField<'tcx>],
         etc: bool,
         def_bm: BindingMode,
         ti: TopInfo<'tcx>,
@@ -1291,7 +1291,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         variant: &VariantDef,
         pat: &'_ Pat<'_>,
-        fields: &[hir::FieldPat<'_>],
+        fields: &[hir::PatField<'_>],
     ) -> Option<DiagnosticBuilder<'_>> {
         // if this is a tuple struct, then all field names will be numbers
         // so if any fields in a struct pattern use shorthand syntax, they will
@@ -1446,7 +1446,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     fn error_tuple_variant_as_struct_pat(
         &self,
         pat: &Pat<'_>,
-        fields: &'tcx [hir::FieldPat<'tcx>],
+        fields: &'tcx [hir::PatField<'tcx>],
         variant: &ty::VariantDef,
     ) -> Option<DiagnosticBuilder<'tcx>> {
         if let (CtorKind::Fn, PatKind::Struct(qpath, ..)) = (variant.ctor_kind, &pat.kind) {
@@ -1484,7 +1484,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
     fn get_suggested_tuple_struct_pattern(
         &self,
-        fields: &[hir::FieldPat<'_>],
+        fields: &[hir::PatField<'_>],
         variant: &VariantDef,
     ) -> String {
         let variant_field_idents = variant.fields.iter().map(|f| f.ident).collect::<Vec<Ident>>();
@@ -1528,7 +1528,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     fn error_no_accessible_fields(
         &self,
         pat: &Pat<'_>,
-        fields: &'tcx [hir::FieldPat<'tcx>],
+        fields: &'tcx [hir::PatField<'tcx>],
     ) -> DiagnosticBuilder<'tcx> {
         let mut err = self
             .tcx
@@ -1574,7 +1574,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         pat: &Pat<'_>,
         unmentioned_fields: &[(&ty::FieldDef, Ident)],
-        fields: &'tcx [hir::FieldPat<'tcx>],
+        fields: &'tcx [hir::PatField<'tcx>],
     ) -> DiagnosticBuilder<'tcx> {
         let field_names = if unmentioned_fields.len() == 1 {
             format!("field `{}`", unmentioned_fields[0].1)

compiler/rustc_typeck/src/expr_use_visitor.rs

@@ -456,7 +456,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
 
     fn walk_struct_expr(
         &mut self,
-        fields: &[hir::Field<'_>],
+        fields: &[hir::ExprField<'_>],
         opt_with: &Option<&'hir hir::Expr<'_>>,
     ) {
         // Consume the expressions supplying values for each field.