Merge #460

460: Name resolution fixes r=flodiebold a=flodiebold

Found two problems:
 - use tree desugaring lost the prefix if the path had just one segment (e.g. in `use foo::{bar, baz}`)
 - when resolving imports across source roots, it actually used the name of the segment from the other source root... so e.g. in `use ra_syntax::foo` it'd map `ra_syntax` to the import instead of `foo` :smile: 

Both of these are one-line fixes, most of this is making it possible to write tests with multiple source roots.

I also left in debug logs for the name resolution, in case it turns out there's still more to fix ;)

Co-authored-by: Florian Diebold <[email protected]>

1 files changed, 125 insertions, 1 deletions

diff --git a/crates/ra_hir/src/nameres/tests.rs b/crates/ra_hir/src/nameres/tests.rs
index 82222d1ad..c511c40b2 100644
--- a/crates/ra_hir/src/nameres/tests.rs
+++ b/crates/ra_hir/src/nameres/tests.rs
@@ -1,7 +1,7 @@
 use std::sync::Arc;
 
 use salsa::Database;
-use ra_db::{FilesDatabase, CrateGraph};
+use ra_db::{FilesDatabase, CrateGraph, SourceRootId};
 use relative_path::RelativePath;
 use test_utils::assert_eq_text;
 
@@ -79,6 +79,35 @@ fn item_map_smoke_test() {
 }
 
 #[test]
+fn use_trees() {
+    let (item_map, module_id) = item_map(
+        "
+        //- /lib.rs
+        mod foo;
+
+        use crate::foo::bar::{Baz, Quux};
+        <|>
+
+        //- /foo/mod.rs
+        pub mod bar;
+
+        //- /foo/bar.rs
+        pub struct Baz;
+        pub enum Quux {};
+    ",
+    );
+    check_module_item_map(
+        &item_map,
+        module_id,
+        "
+            Baz: t v
+            Quux: t
+            foo: t
+        ",
+    );
+}
+
+#[test]
 fn re_exports() {
     let (item_map, module_id) = item_map(
         "
@@ -199,6 +228,101 @@ fn item_map_across_crates() {
 }
 
 #[test]
+fn import_across_source_roots() {
+    let (mut db, sr) = MockDatabase::with_files(
+        "
+        //- /lib.rs
+        pub mod a {
+            pub mod b {
+                pub struct C;
+            }
+        }
+    ",
+    );
+    let lib_id = sr.files[RelativePath::new("/lib.rs")];
+
+    let source_root = SourceRootId(1);
+
+    let (sr2, pos) = db.add_fixture(
+        source_root,
+        "
+        //- /main.rs
+        use test_crate::a::b::C;
+    ",
+    );
+    assert!(pos.is_none());
+
+    let main_id = sr2.files[RelativePath::new("/main.rs")];
+
+    eprintln!("lib = {:?}, main = {:?}", lib_id, main_id);
+
+    let mut crate_graph = CrateGraph::default();
+    let main_crate = crate_graph.add_crate_root(main_id);
+    let lib_crate = crate_graph.add_crate_root(lib_id);
+    crate_graph.add_dep(main_crate, "test_crate".into(), lib_crate);
+
+    db.set_crate_graph(crate_graph);
+
+    let module = crate::source_binder::module_from_file_id(&db, main_id)
+        .unwrap()
+        .unwrap();
+    let module_id = module.def_id.loc(&db).module_id;
+    let item_map = db.item_map(source_root).unwrap();
+
+    check_module_item_map(
+        &item_map,
+        module_id,
+        "
+            C: t v
+            test_crate: t
+        ",
+    );
+}
+
+#[test]
+fn reexport_across_crates() {
+    let (mut db, sr) = MockDatabase::with_files(
+        "
+        //- /main.rs
+        use test_crate::Baz;
+
+        //- /lib.rs
+        pub use foo::Baz;
+
+        mod foo;
+
+        //- /foo.rs
+        pub struct Baz;
+    ",
+    );
+    let main_id = sr.files[RelativePath::new("/main.rs")];
+    let lib_id = sr.files[RelativePath::new("/lib.rs")];
+
+    let mut crate_graph = CrateGraph::default();
+    let main_crate = crate_graph.add_crate_root(main_id);
+    let lib_crate = crate_graph.add_crate_root(lib_id);
+    crate_graph.add_dep(main_crate, "test_crate".into(), lib_crate);
+
+    db.set_crate_graph(crate_graph);
+
+    let source_root = db.file_source_root(main_id);
+    let module = crate::source_binder::module_from_file_id(&db, main_id)
+        .unwrap()
+        .unwrap();
+    let module_id = module.def_id.loc(&db).module_id;
+    let item_map = db.item_map(source_root).unwrap();
+
+    check_module_item_map(
+        &item_map,
+        module_id,
+        "
+            Baz: t v
+            test_crate: t
+        ",
+    );
+}
+
+#[test]
 fn typing_inside_a_function_should_not_invalidate_item_map() {
     let (mut db, pos) = MockDatabase::with_position(
         "