Auto merge of #80782 - petrochenkov:viscopes, r=matthewjasper

resolve: Scope visiting doesn't need an `Ident`

Resolution scope visitor (`fn visit_scopes`) currently takes an `Ident` parameter, but it doesn't need a full identifier, or even its span, it only needs the `SyntaxContext` part.
The `SyntaxContext` part is necessary because scope visitor has to jump to macro definition sites, so it has to be directed by macro expansion information somehow.

I think it's clearer to pass only the necessary part.
Yes, usually visiting happens as a part of an identifier resolution, but in cases like collecting traits in scope (#80765) or collecting typo suggestions that's not the case.

r? `@matthewjasper`

Author: bors

Diff for: compiler/rustc_resolve/src/diagnostics.rs

@@ -611,7 +611,8 @@ impl<'a> Resolver<'a> {
         filter_fn: &impl Fn(Res) -> bool,
     ) -> Option<TypoSuggestion> {
         let mut suggestions = Vec::new();
-        self.visit_scopes(scope_set, parent_scope, ident, |this, scope, use_prelude, _| {
+        let ctxt = ident.span.ctxt();
+        self.visit_scopes(scope_set, parent_scope, ctxt, |this, scope, use_prelude, _| {
             match scope {
                 Scope::DeriveHelpers(expn_id) => {
                     let res = Res::NonMacroAttr(NonMacroAttrKind::DeriveHelper);

Diff for: compiler/rustc_resolve/src/late.rs

@@ -268,52 +268,60 @@ impl<'a> PathSource<'a> {
 
     crate fn is_expected(self, res: Res) -> bool {
         match self {
-            PathSource::Type => matches!(res, Res::Def(
+            PathSource::Type => matches!(
+                res,
+                Res::Def(
                     DefKind::Struct
-                    | DefKind::Union
-                    | DefKind::Enum
-                    | DefKind::Trait
-                    | DefKind::TraitAlias
-                    | DefKind::TyAlias
-                    | DefKind::AssocTy
-                    | DefKind::TyParam
-                    | DefKind::OpaqueTy
-                    | DefKind::ForeignTy,
+                        | DefKind::Union
+                        | DefKind::Enum
+                        | DefKind::Trait
+                        | DefKind::TraitAlias
+                        | DefKind::TyAlias
+                        | DefKind::AssocTy
+                        | DefKind::TyParam
+                        | DefKind::OpaqueTy
+                        | DefKind::ForeignTy,
                     _,
-                )
-                | Res::PrimTy(..)
-                | Res::SelfTy(..)),
+                ) | Res::PrimTy(..)
+                    | Res::SelfTy(..)
+            ),
             PathSource::Trait(AliasPossibility::No) => matches!(res, Res::Def(DefKind::Trait, _)),
             PathSource::Trait(AliasPossibility::Maybe) => {
                 matches!(res, Res::Def(DefKind::Trait | DefKind::TraitAlias, _))
             }
-            PathSource::Expr(..) => matches!(res, Res::Def(
+            PathSource::Expr(..) => matches!(
+                res,
+                Res::Def(
                     DefKind::Ctor(_, CtorKind::Const | CtorKind::Fn)
-                    | DefKind::Const
-                    | DefKind::Static
-                    | DefKind::Fn
-                    | DefKind::AssocFn
-                    | DefKind::AssocConst
-                    | DefKind::ConstParam,
+                        | DefKind::Const
+                        | DefKind::Static
+                        | DefKind::Fn
+                        | DefKind::AssocFn
+                        | DefKind::AssocConst
+                        | DefKind::ConstParam,
                     _,
-                )
-                | Res::Local(..)
-                | Res::SelfCtor(..)),
-            PathSource::Pat => matches!(res, Res::Def(
+                ) | Res::Local(..)
+                    | Res::SelfCtor(..)
+            ),
+            PathSource::Pat => matches!(
+                res,
+                Res::Def(
                     DefKind::Ctor(_, CtorKind::Const) | DefKind::Const | DefKind::AssocConst,
                     _,
-                )
-                | Res::SelfCtor(..)),
+                ) | Res::SelfCtor(..)
+            ),
             PathSource::TupleStruct(..) => res.expected_in_tuple_struct_pat(),
-            PathSource::Struct => matches!(res, Res::Def(
+            PathSource::Struct => matches!(
+                res,
+                Res::Def(
                     DefKind::Struct
-                    | DefKind::Union
-                    | DefKind::Variant
-                    | DefKind::TyAlias
-                    | DefKind::AssocTy,
+                        | DefKind::Union
+                        | DefKind::Variant
+                        | DefKind::TyAlias
+                        | DefKind::AssocTy,
                     _,
-                )
-                | Res::SelfTy(..)),
+                ) | Res::SelfTy(..)
+            ),
             PathSource::TraitItem(ns) => match res {
                 Res::Def(DefKind::AssocConst | DefKind::AssocFn, _) if ns == ValueNS => true,
                 Res::Def(DefKind::AssocTy, _) if ns == TypeNS => true,
@@ -2415,8 +2423,12 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                 &mut found_traits,
                 &self.parent_scope,
             );
-            search_module =
-                unwrap_or!(self.r.hygienic_lexical_parent(search_module, &mut ident.span), break);
+            let mut span_data = ident.span.data();
+            search_module = unwrap_or!(
+                self.r.hygienic_lexical_parent(search_module, &mut span_data.ctxt),
+                break
+            );
+            ident.span = span_data.span();
         }
 
         if let Some(prelude) = self.r.prelude {

Diff for: compiler/rustc_resolve/src/lib.rs

@@ -50,6 +50,7 @@ use rustc_middle::{bug, span_bug};
 use rustc_session::lint;
 use rustc_session::lint::{BuiltinLintDiagnostics, LintBuffer};
 use rustc_session::Session;
+use rustc_span::edition::Edition;
 use rustc_span::hygiene::{ExpnId, ExpnKind, MacroKind, SyntaxContext, Transparency};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
@@ -763,10 +764,13 @@ impl<'a> NameBinding<'a> {
     }
 
     fn is_variant(&self) -> bool {
-        matches!(self.kind, NameBindingKind::Res(
+        matches!(
+            self.kind,
+            NameBindingKind::Res(
                 Res::Def(DefKind::Variant | DefKind::Ctor(CtorOf::Variant, ..), _),
                 _,
-            ))
+            )
+        )
     }
 
     fn is_extern_crate(&self) -> bool {
@@ -1630,8 +1634,13 @@ impl<'a> Resolver<'a> {
         &mut self,
         scope_set: ScopeSet,
         parent_scope: &ParentScope<'a>,
-        ident: Ident,
-        mut visitor: impl FnMut(&mut Self, Scope<'a>, /*use_prelude*/ bool, Ident) -> Option<T>,
+        ctxt: SyntaxContext,
+        mut visitor: impl FnMut(
+            &mut Self,
+            Scope<'a>,
+            /*use_prelude*/ bool,
+            SyntaxContext,
+        ) -> Option<T>,
     ) -> Option<T> {
         // General principles:
         // 1. Not controlled (user-defined) names should have higher priority than controlled names
@@ -1674,7 +1683,7 @@ impl<'a> Resolver<'a> {
         // 4c. Standard library prelude (de-facto closed, controlled).
         // 6. Language prelude: builtin attributes (closed, controlled).
 
-        let rust_2015 = ident.span.rust_2015();
+        let rust_2015 = ctxt.edition() == Edition::Edition2015;
         let (ns, macro_kind, is_absolute_path) = match scope_set {
             ScopeSet::All(ns, _) => (ns, None, false),
             ScopeSet::AbsolutePath(ns) => (ns, None, true),
@@ -1687,7 +1696,7 @@ impl<'a> Resolver<'a> {
             TypeNS | ValueNS => Scope::Module(module),
             MacroNS => Scope::DeriveHelpers(parent_scope.expansion),
         };
-        let mut ident = ident.normalize_to_macros_2_0();
+        let mut ctxt = ctxt.normalize_to_macros_2_0();
         let mut use_prelude = !module.no_implicit_prelude;
 
         loop {
@@ -1723,7 +1732,7 @@ impl<'a> Resolver<'a> {
             };
 
             if visit {
-                if let break_result @ Some(..) = visitor(self, scope, use_prelude, ident) {
+                if let break_result @ Some(..) = visitor(self, scope, use_prelude, ctxt) {
                     return break_result;
                 }
             }
@@ -1753,17 +1762,17 @@ impl<'a> Resolver<'a> {
                 },
                 Scope::CrateRoot => match ns {
                     TypeNS => {
-                        ident.span.adjust(ExpnId::root());
+                        ctxt.adjust(ExpnId::root());
                         Scope::ExternPrelude
                     }
                     ValueNS | MacroNS => break,
                 },
                 Scope::Module(module) => {
                     use_prelude = !module.no_implicit_prelude;
-                    match self.hygienic_lexical_parent(module, &mut ident.span) {
+                    match self.hygienic_lexical_parent(module, &mut ctxt) {
                         Some(parent_module) => Scope::Module(parent_module),
                         None => {
-                            ident.span.adjust(ExpnId::root());
+                            ctxt.adjust(ExpnId::root());
                             match ns {
                                 TypeNS => Scope::ExternPrelude,
                                 ValueNS => Scope::StdLibPrelude,
@@ -1888,16 +1897,18 @@ impl<'a> Resolver<'a> {
         ident = normalized_ident;
         let mut poisoned = None;
         loop {
+            let mut span_data = ident.span.data();
             let opt_module = if let Some(node_id) = record_used_id {
                 self.hygienic_lexical_parent_with_compatibility_fallback(
                     module,
-                    &mut ident.span,
+                    &mut span_data.ctxt,
                     node_id,
                     &mut poisoned,
                 )
             } else {
-                self.hygienic_lexical_parent(module, &mut ident.span)
+                self.hygienic_lexical_parent(module, &mut span_data.ctxt)
             };
+            ident.span = span_data.span();
             module = unwrap_or!(opt_module, break);
             let adjusted_parent_scope = &ParentScope { module, ..*parent_scope };
             let result = self.resolve_ident_in_module_unadjusted(
@@ -1971,10 +1982,10 @@ impl<'a> Resolver<'a> {
     fn hygienic_lexical_parent(
         &mut self,
         module: Module<'a>,
-        span: &mut Span,
+        ctxt: &mut SyntaxContext,
     ) -> Option<Module<'a>> {
-        if !module.expansion.outer_expn_is_descendant_of(span.ctxt()) {
-            return Some(self.macro_def_scope(span.remove_mark()));
+        if !module.expansion.outer_expn_is_descendant_of(*ctxt) {
+            return Some(self.macro_def_scope(ctxt.remove_mark()));
         }
 
         if let ModuleKind::Block(..) = module.kind {
@@ -1987,11 +1998,11 @@ impl<'a> Resolver<'a> {
     fn hygienic_lexical_parent_with_compatibility_fallback(
         &mut self,
         module: Module<'a>,
-        span: &mut Span,
+        ctxt: &mut SyntaxContext,
         node_id: NodeId,
         poisoned: &mut Option<NodeId>,
     ) -> Option<Module<'a>> {
-        if let module @ Some(..) = self.hygienic_lexical_parent(module, span) {
+        if let module @ Some(..) = self.hygienic_lexical_parent(module, ctxt) {
             return module;
         }
 
@@ -2016,7 +2027,7 @@ impl<'a> Resolver<'a> {
                     let ext = self.get_macro_by_def_id(def_id);
                     if ext.builtin_name.is_none()
                         && ext.macro_kind() == MacroKind::Derive
-                        && parent.expansion.outer_expn_is_descendant_of(span.ctxt())
+                        && parent.expansion.outer_expn_is_descendant_of(*ctxt)
                     {
                         *poisoned = Some(node_id);
                         return module.parent;

Diff for: compiler/rustc_resolve/src/macros.rs

@@ -618,8 +618,9 @@ impl<'a> Resolver<'a> {
         let break_result = self.visit_scopes(
             scope_set,
             parent_scope,
-            orig_ident,
-            |this, scope, use_prelude, ident| {
+            orig_ident.span.ctxt(),
+            |this, scope, use_prelude, ctxt| {
+                let ident = Ident::new(orig_ident.name, orig_ident.span.with_ctxt(ctxt));
                 let ok = |res, span, arenas| {
                     Ok((
                         (res, ty::Visibility::Public, span, ExpnId::root()).to_name_binding(arenas),

Diff for: compiler/rustc_span/src/hygiene.rs

@@ -622,6 +622,10 @@ impl SyntaxContext {
     pub fn dollar_crate_name(self) -> Symbol {
         HygieneData::with(|data| data.syntax_context_data[self.0 as usize].dollar_crate_name)
     }
+
+    pub fn edition(self) -> Edition {
+        self.outer_expn_data().edition
+    }
 }
 
 impl fmt::Debug for SyntaxContext {

Diff for: compiler/rustc_span/src/lib.rs

@@ -300,6 +300,10 @@ pub struct SpanData {
 }
 
 impl SpanData {
+    #[inline]
+    pub fn span(&self) -> Span {
+        Span::new(self.lo, self.hi, self.ctxt)
+    }
     #[inline]
     pub fn with_lo(&self, lo: BytePos) -> Span {
         Span::new(lo, self.hi, self.ctxt)
@@ -468,7 +472,7 @@ impl Span {
 
     /// Edition of the crate from which this span came.
     pub fn edition(self) -> edition::Edition {
-        self.ctxt().outer_expn_data().edition
+        self.ctxt().edition()
     }
 
     #[inline]