Change syntax for TyAlias where clauses

3 files changed, 41 insertions, 6 deletions

diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index 725499e5c78..2fbafca1681 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -2662,10 +2662,23 @@ pub struct Trait {
     pub items: Vec<P<AssocItem>>,
 }
 
+/// The location of a where clause on a `TyAlias` (`Span`) and whether there was
+/// a `where` keyword (`bool`). This is split out from `WhereClause`, since there
+/// are two locations for where clause on type aliases, but their predicates
+/// are concatenated together.
+#[derive(Copy, Clone, Encodable, Decodable, Debug, Default)]
+pub struct TyAliasWhereClause(pub bool, pub Span);
+
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub struct TyAlias {
     pub defaultness: Defaultness,
     pub generics: Generics,
+    /// The span information for the two where clauses (before equals, after equals)
+    pub where_clauses: (TyAliasWhereClause, TyAliasWhereClause),
+    /// The index in `generics.where_clause.predicates` that would split into
+    /// predicates from the where clause before the equals and the predicates
+    /// from the where clause after the equals
+    pub where_predicates_split: usize,
     pub bounds: GenericBounds,
     pub ty: Option<P<Ty>>,
 }
diff --git a/compiler/rustc_ast/src/mut_visit.rs b/compiler/rustc_ast/src/mut_visit.rs
index a81a2276295..c60c77e6987 100644
--- a/compiler/rustc_ast/src/mut_visit.rs
+++ b/compiler/rustc_ast/src/mut_visit.rs
@@ -1018,9 +1018,13 @@ pub fn noop_visit_item_kind<T: MutVisitor>(kind: &mut ItemKind, vis: &mut T) {
         }
         ItemKind::ForeignMod(nm) => vis.visit_foreign_mod(nm),
         ItemKind::GlobalAsm(asm) => noop_visit_inline_asm(asm, vis),
-        ItemKind::TyAlias(box TyAlias { defaultness, generics, bounds, ty }) => {
+        ItemKind::TyAlias(box TyAlias {
+            defaultness, generics, where_clauses, bounds, ty, ..
+        }) => {
             visit_defaultness(defaultness, vis);
             vis.visit_generics(generics);
+            vis.visit_span(&mut where_clauses.0.1);
+            vis.visit_span(&mut where_clauses.1.1);
             visit_bounds(bounds, vis);
             visit_opt(ty, |ty| vis.visit_ty(ty));
         }
@@ -1087,9 +1091,18 @@ pub fn noop_flat_map_assoc_item<T: MutVisitor>(
             visit_fn_sig(sig, visitor);
             visit_opt(body, |body| visitor.visit_block(body));
         }
-        AssocItemKind::TyAlias(box TyAlias { defaultness, generics, bounds, ty }) => {
+        AssocItemKind::TyAlias(box TyAlias {
+            defaultness,
+            generics,
+            where_clauses,
+            bounds,
+            ty,
+            ..
+        }) => {
             visit_defaultness(defaultness, visitor);
             visitor.visit_generics(generics);
+            visitor.visit_span(&mut where_clauses.0.1);
+            visitor.visit_span(&mut where_clauses.1.1);
             visit_bounds(bounds, visitor);
             visit_opt(ty, |ty| visitor.visit_ty(ty));
         }
@@ -1152,9 +1165,18 @@ pub fn noop_flat_map_foreign_item<T: MutVisitor>(
             visit_fn_sig(sig, visitor);
             visit_opt(body, |body| visitor.visit_block(body));
         }
-        ForeignItemKind::TyAlias(box TyAlias { defaultness, generics, bounds, ty }) => {
+        ForeignItemKind::TyAlias(box TyAlias {
+            defaultness,
+            generics,
+            where_clauses,
+            bounds,
+            ty,
+            ..
+        }) => {
             visit_defaultness(defaultness, visitor);
             visitor.visit_generics(generics);
+            visitor.visit_span(&mut where_clauses.0.1);
+            visitor.visit_span(&mut where_clauses.1.1);
             visit_bounds(bounds, visitor);
             visit_opt(ty, |ty| visitor.visit_ty(ty));
         }
diff --git a/compiler/rustc_ast/src/visit.rs b/compiler/rustc_ast/src/visit.rs
index 73e9297549c..ed16c25d921 100644
--- a/compiler/rustc_ast/src/visit.rs
+++ b/compiler/rustc_ast/src/visit.rs
@@ -303,7 +303,7 @@ pub fn walk_item<'a, V: Visitor<'a>>(visitor: &mut V, item: &'a Item) {
             walk_list!(visitor, visit_foreign_item, &foreign_module.items);
         }
         ItemKind::GlobalAsm(ref asm) => walk_inline_asm(visitor, asm),
-        ItemKind::TyAlias(box TyAlias { defaultness: _, ref generics, ref bounds, ref ty }) => {
+        ItemKind::TyAlias(box TyAlias { ref generics, ref bounds, ref ty, .. }) => {
             visitor.visit_generics(generics);
             walk_list!(visitor, visit_param_bound, bounds);
             walk_list!(visitor, visit_ty, ty);
@@ -559,7 +559,7 @@ pub fn walk_foreign_item<'a, V: Visitor<'a>>(visitor: &mut V, item: &'a ForeignI
             let kind = FnKind::Fn(FnCtxt::Foreign, ident, sig, vis, body.as_deref());
             visitor.visit_fn(kind, span, id);
         }
-        ForeignItemKind::TyAlias(box TyAlias { defaultness: _, generics, bounds, ty }) => {
+        ForeignItemKind::TyAlias(box TyAlias { generics, bounds, ty, .. }) => {
             visitor.visit_generics(generics);
             walk_list!(visitor, visit_param_bound, bounds);
             walk_list!(visitor, visit_ty, ty);
@@ -665,7 +665,7 @@ pub fn walk_assoc_item<'a, V: Visitor<'a>>(visitor: &mut V, item: &'a AssocItem,
             let kind = FnKind::Fn(FnCtxt::Assoc(ctxt), ident, sig, vis, body.as_deref());
             visitor.visit_fn(kind, span, id);
         }
-        AssocItemKind::TyAlias(box TyAlias { defaultness: _, generics, bounds, ty }) => {
+        AssocItemKind::TyAlias(box TyAlias { generics, bounds, ty, .. }) => {
             visitor.visit_generics(generics);
             walk_list!(visitor, visit_param_bound, bounds);
             walk_list!(visitor, visit_ty, ty);