3 files changed, 68 insertions, 28 deletions

diff --git a/crates/hir_def/src/nameres/collector.rs b/crates/hir_def/src/nameres/collector.rs
index 81cf652b0..d0fefb5af 100644
--- a/crates/hir_def/src/nameres/collector.rs
+++ b/crates/hir_def/src/nameres/collector.rs
@@ -242,7 +242,7 @@ struct DefCollector<'a> {
 impl DefCollector<'_> {
     fn seed_with_top_level(&mut self) {
         let file_id = self.db.crate_graph()[self.def_map.krate].root_file_id;
-        let item_tree = self.db.item_tree(file_id.into());
+        let item_tree = self.db.file_item_tree(file_id.into());
         let module_id = self.def_map.root;
         self.def_map.modules[module_id].origin = ModuleOrigin::CrateRoot { definition: file_id };
         if item_tree
@@ -263,7 +263,7 @@ impl DefCollector<'_> {
     }
 
     fn seed_with_inner(&mut self, block: AstId<ast::BlockExpr>) {
-        let item_tree = self.db.item_tree(block.file_id);
+        let item_tree = self.db.file_item_tree(block.file_id);
         let module_id = self.def_map.root;
         self.def_map.modules[module_id].origin = ModuleOrigin::BlockExpr { block };
         if item_tree
@@ -656,26 +656,28 @@ impl DefCollector<'_> {
                 }
             }
         } else {
-            match import.path.segments().last() {
-                Some(last_segment) => {
-                    let name = match &import.alias {
-                        Some(ImportAlias::Alias(name)) => Some(name.clone()),
-                        Some(ImportAlias::Underscore) => None,
-                        None => Some(last_segment.clone()),
-                    };
-                    log::debug!("resolved import {:?} ({:?}) to {:?}", name, import, def);
-
-                    // extern crates in the crate root are special-cased to insert entries into the extern prelude: rust-lang/rust#54658
-                    if import.is_extern_crate && module_id == self.def_map.root {
-                        if let (Some(def), Some(name)) = (def.take_types(), name.as_ref()) {
-                            self.def_map.extern_prelude.insert(name.clone(), def);
-                        }
+            let name = match &import.alias {
+                Some(ImportAlias::Alias(name)) => Some(name.clone()),
+                Some(ImportAlias::Underscore) => None,
+                None => match import.path.segments().last() {
+                    Some(last_segment) => Some(last_segment.clone()),
+                    None => {
+                        cov_mark::hit!(bogus_paths);
+                        return;
                     }
+                },
+            };
+
+            log::debug!("resolved import {:?} ({:?}) to {:?}", name, import, def);
 
-                    self.update(module_id, &[(name, def)], vis, ImportType::Named);
+            // extern crates in the crate root are special-cased to insert entries into the extern prelude: rust-lang/rust#54658
+            if import.is_extern_crate && module_id == self.def_map.root {
+                if let (Some(def), Some(name)) = (def.take_types(), name.as_ref()) {
+                    self.def_map.extern_prelude.insert(name.clone(), def);
                 }
-                None => cov_mark::hit!(bogus_paths),
             }
+
+            self.update(module_id, &[(name, def)], vis, ImportType::Named);
         }
     }
 
@@ -893,7 +895,7 @@ impl DefCollector<'_> {
         }
 
         // Then, fetch and process the item tree. This will reuse the expansion result from above.
-        let item_tree = self.db.item_tree(file_id);
+        let item_tree = self.db.file_item_tree(file_id);
         let mod_dir = self.mod_dirs[&module_id].clone();
         ModCollector {
             def_collector: &mut *self,
@@ -949,21 +951,21 @@ impl DefCollector<'_> {
         let mut diagnosed_extern_crates = FxHashSet::default();
         for directive in &self.unresolved_imports {
             if let ImportSource::ExternCrate(krate) = directive.import.source {
-                let item_tree = self.db.item_tree(krate.file_id);
+                let item_tree = krate.item_tree(self.db);
                 let extern_crate = &item_tree[krate.value];
 
                 diagnosed_extern_crates.insert(extern_crate.name.clone());
 
                 self.def_map.diagnostics.push(DefDiagnostic::unresolved_extern_crate(
                     directive.module_id,
-                    InFile::new(krate.file_id, extern_crate.ast_id),
+                    InFile::new(krate.file_id(), extern_crate.ast_id),
                 ));
             }
         }
 
         for directive in &self.unresolved_imports {
             if let ImportSource::Import(import) = &directive.import.source {
-                let item_tree = self.db.item_tree(import.file_id);
+                let item_tree = import.item_tree(self.db);
                 let import_data = &item_tree[import.value];
 
                 match (import_data.path.segments().first(), &import_data.path.kind) {
@@ -977,7 +979,7 @@ impl DefCollector<'_> {
 
                 self.def_map.diagnostics.push(DefDiagnostic::unresolved_import(
                     directive.module_id,
-                    InFile::new(import.file_id, import_data.ast_id),
+                    InFile::new(import.file_id(), import_data.ast_id),
                     import_data.index,
                 ));
             }
@@ -1053,7 +1055,7 @@ impl ModCollector<'_, '_> {
                             self.def_collector.db,
                             krate,
                             &self.item_tree,
-                            InFile::new(self.file_id, import_id),
+                            ItemTreeId::new(self.file_id, import_id),
                         ),
                         status: PartialResolvedImport::Unresolved,
                     })
@@ -1065,7 +1067,7 @@ impl ModCollector<'_, '_> {
                             self.def_collector.db,
                             krate,
                             &self.item_tree,
-                            InFile::new(self.file_id, import_id),
+                            ItemTreeId::new(self.file_id, import_id),
                         ),
                         status: PartialResolvedImport::Unresolved,
                     })
@@ -1297,7 +1299,7 @@ impl ModCollector<'_, '_> {
                             Some((file_id, is_mod_rs)),
                             &self.item_tree[module.visibility],
                         );
-                        let item_tree = db.item_tree(file_id.into());
+                        let item_tree = db.file_item_tree(file_id.into());
                         ModCollector {
                             def_collector: &mut *self.def_collector,
                             macro_depth: self.macro_depth,
@@ -1469,7 +1471,9 @@ impl ModCollector<'_, '_> {
                     )
                 })
             },
-            &mut |err| error = Some(err),
+            &mut |err| {
+                error.get_or_insert(err);
+            },
         ) {
             Ok(Ok(macro_call_id)) => {
                 self.def_collector.unexpanded_macros.push(MacroDirective {
diff --git a/crates/hir_def/src/nameres/tests.rs b/crates/hir_def/src/nameres/tests.rs
index de3aa4f9a..4f2e7a2f9 100644
--- a/crates/hir_def/src/nameres/tests.rs
+++ b/crates/hir_def/src/nameres/tests.rs
@@ -713,3 +713,22 @@ pub fn f() {}
         "#]],
     );
 }
+
+#[test]
+fn use_crate_as() {
+    check(
+        r#"
+use crate as foo;
+
+use foo::bar as baz;
+
+fn bar() {}
+        "#,
+        expect![[r#"
+            crate
+            bar: v
+            baz: v
+            foo: t
+        "#]],
+    );
+}
diff --git a/crates/hir_def/src/nameres/tests/diagnostics.rs b/crates/hir_def/src/nameres/tests/diagnostics.rs
index c22ef46fd..a89061c2e 100644
--- a/crates/hir_def/src/nameres/tests/diagnostics.rs
+++ b/crates/hir_def/src/nameres/tests/diagnostics.rs
@@ -196,7 +196,24 @@ fn builtin_macro_fails_expansion() {
           macro_rules! include { () => {} }
 
           include!("doesntexist");
-        //^^^^^^^^^^^^^^^^^^^^^^^^ could not convert tokens
+        //^^^^^^^^^^^^^^^^^^^^^^^^ failed to load file `doesntexist`
+        "#,
+    );
+}
+
+#[test]
+fn good_out_dir_diagnostic() {
+    check_diagnostics(
+        r#"
+        #[rustc_builtin_macro]
+        macro_rules! include { () => {} }
+        #[rustc_builtin_macro]
+        macro_rules! env { () => {} }
+        #[rustc_builtin_macro]
+        macro_rules! concat { () => {} }
+
+        include!(concat!(env!("OUT_DIR"), "/out.rs"));
+      //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `OUT_DIR` not set, enable "load out dirs from check" to fix
         "#,
     );
 }