Merge #742

742: Extern crate r=matklad a=flodiebold

This implements `extern crate` declarations by lowering them to (absolute) imports, and adds support for absolute paths. It also extracts the extern prelude from the per-module item map, and handles the special case of extern crates in the crate root adding to the extern prelude.

This means we finally resolve `Arc`, so it fixes #523 :smile: 

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

1 files changed, 43 insertions, 5 deletions

diff --git a/crates/ra_hir/src/nameres/tests.rs b/crates/ra_hir/src/nameres/tests.rs
index 81c8a4f12..0654dbaa1 100644
--- a/crates/ra_hir/src/nameres/tests.rs
+++ b/crates/ra_hir/src/nameres/tests.rs
@@ -329,7 +329,49 @@ fn item_map_across_crates() {
         module.module_id,
         "
             Baz: t v
-            test_crate: t
+        ",
+    );
+}
+
+#[test]
+fn extern_crate_rename() {
+    let (mut db, sr) = MockDatabase::with_files(
+        "
+        //- /main.rs
+        extern crate alloc as alloc_crate;
+
+        mod alloc;
+        mod sync;
+
+        //- /sync.rs
+        use alloc_crate::Arc;
+
+        //- /lib.rs
+        struct Arc;
+    ",
+    );
+    let main_id = sr.files[RelativePath::new("/main.rs")];
+    let sync_id = sr.files[RelativePath::new("/sync.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, "alloc".into(), lib_crate)
+        .unwrap();
+
+    db.set_crate_graph(Arc::new(crate_graph));
+
+    let module = crate::source_binder::module_from_file_id(&db, sync_id).unwrap();
+    let krate = module.krate(&db).unwrap();
+    let item_map = db.item_map(krate);
+
+    check_module_item_map(
+        &item_map,
+        module.module_id,
+        "
+            Arc: t v
         ",
     );
 }
@@ -361,8 +403,6 @@ fn import_across_source_roots() {
 
     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);
@@ -381,7 +421,6 @@ fn import_across_source_roots() {
         module.module_id,
         "
             C: t v
-            test_crate: t
         ",
     );
 }
@@ -423,7 +462,6 @@ fn reexport_across_crates() {
         module.module_id,
         "
             Baz: t v
-            test_crate: t
         ",
     );
 }