3 files changed, 26 insertions, 5 deletions

diff --git a/crates/hir/src/code_model.rs b/crates/hir/src/code_model.rs
index 8ffb9e99b..5dc3ae3b1 100644
--- a/crates/hir/src/code_model.rs
+++ b/crates/hir/src/code_model.rs
@@ -883,6 +883,13 @@ where
 }
 
 impl AssocItem {
+    pub fn name(self, db: &dyn HirDatabase) -> Option<Name> {
+        match self {
+            AssocItem::Function(it) => Some(it.name(db)),
+            AssocItem::Const(it) => it.name(db),
+            AssocItem::TypeAlias(it) => Some(it.name(db)),
+        }
+    }
     pub fn module(self, db: &dyn HirDatabase) -> Module {
         match self {
             AssocItem::Function(f) => f.module(db),
diff --git a/crates/hir/src/lib.rs b/crates/hir/src/lib.rs
index 24a0f6b4b..4ae2bd085 100644
--- a/crates/hir/src/lib.rs
+++ b/crates/hir/src/lib.rs
@@ -52,8 +52,12 @@ pub use hir_def::{
     type_ref::{Mutability, TypeRef},
 };
 pub use hir_expand::{
-    hygiene::Hygiene, name::Name, HirFileId, InFile, MacroCallId, MacroCallLoc,
-    MacroDefId, /* FIXME */
+    name::Name, HirFileId, InFile, MacroCallId, MacroCallLoc, /* FIXME */ MacroDefId,
     MacroFile, Origin,
 };
 pub use hir_ty::display::HirDisplay;
+
+// These are negative re-exports: pub using these names is forbidden, they
+// should remain private to hir internals.
+#[allow(unused)]
+use hir_expand::hygiene::Hygiene;
diff --git a/crates/hir/src/semantics.rs b/crates/hir/src/semantics.rs
index 1467d825d..d8beac98a 100644
--- a/crates/hir/src/semantics.rs
+++ b/crates/hir/src/semantics.rs
@@ -502,18 +502,19 @@ impl<'db> SemanticsImpl<'db> {
     fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db> {
         let node = self.find_file(node.clone());
         let resolver = self.analyze2(node.as_ref(), None).resolver;
-        SemanticsScope { db: self.db, resolver }
+        SemanticsScope { db: self.db, file_id: node.file_id, resolver }
     }
 
     fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> SemanticsScope<'db> {
         let node = self.find_file(node.clone());
         let resolver = self.analyze2(node.as_ref(), Some(offset)).resolver;
-        SemanticsScope { db: self.db, resolver }
+        SemanticsScope { db: self.db, file_id: node.file_id, resolver }
     }
 
     fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
+        let file_id = self.db.lookup_intern_trait(def.id).id.file_id;
         let resolver = def.id.resolver(self.db.upcast());
-        SemanticsScope { db: self.db, resolver }
+        SemanticsScope { db: self.db, file_id, resolver }
     }
 
     fn analyze(&self, node: &SyntaxNode) -> SourceAnalyzer {
@@ -709,6 +710,7 @@ fn find_root(node: &SyntaxNode) -> SyntaxNode {
 #[derive(Debug)]
 pub struct SemanticsScope<'a> {
     pub db: &'a dyn HirDatabase,
+    file_id: HirFileId,
     resolver: Resolver,
 }
 
@@ -752,6 +754,14 @@ impl<'a> SemanticsScope<'a> {
         })
     }
 
+    /// Resolve a path as-if it was written at the given scope. This is
+    /// necessary a heuristic, as it doesn't take hygiene into account.
+    pub fn resolve_hypothetical(&self, path: &ast::Path) -> Option<PathResolution> {
+        let hygiene = Hygiene::new(self.db.upcast(), self.file_id);
+        let path = Path::from_src(path.clone(), &hygiene)?;
+        self.resolve_hir_path(&path)
+    }
+
     pub fn resolve_hir_path(&self, path: &Path) -> Option<PathResolution> {
         resolve_hir_path(self.db, &self.resolver, path)
     }