Some refactoring

3 files changed, 25 insertions, 21 deletions

diff --git a/compiler/rustc_resolve/src/diagnostics.rs b/compiler/rustc_resolve/src/diagnostics.rs
index 7493fd68505..d402fa4f849 100644
--- a/compiler/rustc_resolve/src/diagnostics.rs
+++ b/compiler/rustc_resolve/src/diagnostics.rs
@@ -450,12 +450,12 @@ impl<'a> Resolver<'a> {
                     self.session,
                     span,
                     E0128,
-                    "type parameters with a default cannot use \
+                    "generic parameters with a default cannot use \
                                                 forward declared identifiers"
                 );
                 err.span_label(
                     span,
-                    "defaulted type parameters cannot be forward declared".to_string(),
+                    "defaulted generic parameters cannot be forward declared".to_string(),
                 );
                 err
             }
diff --git a/compiler/rustc_resolve/src/late.rs b/compiler/rustc_resolve/src/late.rs
index 85faa961b14..f9f33492a1e 100644
--- a/compiler/rustc_resolve/src/late.rs
+++ b/compiler/rustc_resolve/src/late.rs
@@ -132,10 +132,10 @@ crate enum RibKind<'a> {
     /// We passed through a `macro_rules!` statement
     MacroDefinition(DefId),
 
-    /// All bindings in this rib are type parameters that can't be used
-    /// from the default of a type parameter because they're not declared
-    /// before said type parameter. Also see the `visit_generics` override.
-    ForwardTyParamBanRibKind,
+    /// All bindings in this rib are generic parameters that can't be used
+    /// from the default of a generic parameter because they're not declared
+    /// before said generic parameter. Also see the `visit_generics` override.
+    ForwardGenericParamBanRibKind,
 
     /// We are inside of the type of a const parameter. Can't refer to any
     /// parameters.
@@ -154,7 +154,7 @@ impl RibKind<'_> {
             | ModuleRibKind(_)
             | MacroDefinition(_)
             | ConstParamTyRibKind => false,
-            AssocItemRibKind | ItemRibKind(_) | ForwardTyParamBanRibKind => true,
+            AssocItemRibKind | ItemRibKind(_) | ForwardGenericParamBanRibKind => true,
         }
     }
 }
@@ -555,15 +555,16 @@ impl<'a: 'ast, 'ast> Visitor<'ast> for LateResolutionVisitor<'a, '_, 'ast> {
         // provide previous type parameters as they're built. We
         // put all the parameters on the ban list and then remove
         // them one by one as they are processed and become available.
-        let mut default_ban_rib = Rib::new(ForwardTyParamBanRibKind);
+        let mut default_ban_rib = Rib::new(ForwardGenericParamBanRibKind);
         let mut found_default = false;
         default_ban_rib.bindings.extend(generics.params.iter().filter_map(
             |param| match param.kind {
-                GenericParamKind::Const { .. } | GenericParamKind::Lifetime { .. } => None,
-                GenericParamKind::Type { ref default, .. } => {
-                    found_default |= default.is_some();
-                    found_default.then_some((Ident::with_dummy_span(param.ident.name), Res::Err))
+                GenericParamKind::Type { default: Some(_), .. }
+                | GenericParamKind::Const { default: Some(_), .. } => {
+                    found_default = true;
+                    Some((Ident::with_dummy_span(param.ident.name), Res::Err))
                 }
+                _ => None,
             },
         ));
 
@@ -591,8 +592,8 @@ impl<'a: 'ast, 'ast> Visitor<'ast> for LateResolutionVisitor<'a, '_, 'ast> {
 
                     if let Some(ref ty) = default {
                         self.ribs[TypeNS].push(default_ban_rib);
-                        self.with_rib(ValueNS, ForwardTyParamBanRibKind, |this| {
-                            // HACK: We use an empty `ForwardTyParamBanRibKind` here which
+                        self.with_rib(ValueNS, ForwardGenericParamBanRibKind, |this| {
+                            // HACK: We use an empty `ForwardGenericParamBanRibKind` here which
                             // is only used to forbid the use of const parameters inside of
                             // type defaults.
                             //
@@ -616,7 +617,6 @@ impl<'a: 'ast, 'ast> Visitor<'ast> for LateResolutionVisitor<'a, '_, 'ast> {
                     self.visit_ty(ty);
                     self.ribs[TypeNS].pop().unwrap();
                     self.ribs[ValueNS].pop().unwrap();
-                    // FIXME(const_generics:default) do something with default here?
                 }
             }
         }
@@ -866,7 +866,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                 | ItemRibKind(..)
                 | ConstantItemRibKind(..)
                 | ModuleRibKind(..)
-                | ForwardTyParamBanRibKind
+                | ForwardGenericParamBanRibKind
                 | ConstParamTyRibKind => {
                     return false;
                 }
diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs
index d8f201fd0d8..4eda1220599 100644
--- a/compiler/rustc_resolve/src/lib.rs
+++ b/compiler/rustc_resolve/src/lib.rs
@@ -2592,8 +2592,8 @@ impl<'a> Resolver<'a> {
         debug!("validate_res_from_ribs({:?})", res);
         let ribs = &all_ribs[rib_index + 1..];
 
-        // An invalid forward use of a type parameter from a previous default.
-        if let ForwardTyParamBanRibKind = all_ribs[rib_index].kind {
+        // An invalid forward use of a generic parameter from a previous default.
+        if let ForwardGenericParamBanRibKind = all_ribs[rib_index].kind {
             if record_used {
                 let res_error = if rib_ident.name == kw::SelfUpper {
                     ResolutionError::SelfInTyParamDefault
@@ -2617,7 +2617,7 @@ impl<'a> Resolver<'a> {
                         | ClosureOrAsyncRibKind
                         | ModuleRibKind(..)
                         | MacroDefinition(..)
-                        | ForwardTyParamBanRibKind => {
+                        | ForwardGenericParamBanRibKind => {
                             // Nothing to do. Continue.
                         }
                         ItemRibKind(_) | FnItemRibKind | AssocItemRibKind => {
@@ -2689,7 +2689,9 @@ impl<'a> Resolver<'a> {
 
                         // We only forbid constant items if we are inside of type defaults,
                         // for example `struct Foo<T, U = [u8; std::mem::size_of::<T>()]>`
-                        ForwardTyParamBanRibKind => {
+                        ForwardGenericParamBanRibKind => {
+                            // FIXME(const_generic_defaults): we may need to distinguish between
+                            // being in type parameter defaults and const parameter defaults
                             in_ty_param_default = true;
                             continue;
                         }
@@ -2782,7 +2784,9 @@ impl<'a> Resolver<'a> {
 
                         // We only forbid constant items if we are inside of type defaults,
                         // for example `struct Foo<T, U = [u8; std::mem::size_of::<T>()]>`
-                        ForwardTyParamBanRibKind => {
+                        ForwardGenericParamBanRibKind => {
+                            // FIXME(const_generic_defaults): we may need to distinguish between
+                            // being in type parameter defaults and const parameter defaults
                             in_ty_param_default = true;
                             continue;
                         }