add new ImportAlias enum to differentiate no alias from an _ alias

1 files changed, 13 insertions, 2 deletions

diff --git a/crates/ra_hir_def/src/nameres/raw.rs b/crates/ra_hir_def/src/nameres/raw.rs
index fac1169ef..f068b4d4e 100644
--- a/crates/ra_hir_def/src/nameres/raw.rs
+++ b/crates/ra_hir_def/src/nameres/raw.rs
@@ -145,7 +145,7 @@ impl_arena_id!(Import);
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct ImportData {
     pub(super) path: ModPath,
-    pub(super) alias: Option<Name>,
+    pub(super) alias: ImportAlias,
     pub(super) is_glob: bool,
     pub(super) is_prelude: bool,
     pub(super) is_extern_crate: bool,
@@ -153,6 +153,13 @@ pub struct ImportData {
     pub(super) visibility: RawVisibility,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum ImportAlias {
+    NoAlias,
+    Unnamed, // use Foo as _;
+    Alias(Name),
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub(super) struct Def(RawId);
 impl_arena_id!(Def);
@@ -353,7 +360,11 @@ impl RawItemsCollector {
             let path = ModPath::from_name_ref(&name_ref);
             let visibility =
                 RawVisibility::from_ast_with_hygiene(extern_crate.visibility(), &self.hygiene);
-            let alias = extern_crate.alias().and_then(|a| a.name()).map(|it| it.as_name());
+            let alias = extern_crate.alias().map_or(ImportAlias::NoAlias, |a| {
+                a.name()
+                    .map(|it| it.as_name())
+                    .map_or(ImportAlias::Unnamed, |a| ImportAlias::Alias(a))
+            });
             let attrs = self.parse_attrs(&extern_crate);
             // FIXME: cfg_attr
             let is_macro_use = extern_crate.has_atom_attr("macro_use");