3 files changed, 63 insertions, 9 deletions

diff --git a/crates/libanalysis/Cargo.toml b/crates/libanalysis/Cargo.toml
index 42a5aca14..fa859ff94 100644
--- a/crates/libanalysis/Cargo.toml
+++ b/crates/libanalysis/Cargo.toml
@@ -12,3 +12,6 @@ rayon = "1.0.2"
 fst = { git = "https://github.com/matklad/fst", branch = "subsequence"}
 libsyntax2 = { path = "../libsyntax2" }
 libeditor = { path = "../libeditor" }
+
+[dev-dependencies]
+assert_eq_text = { path = "../assert_eq_text" }
diff --git a/crates/libanalysis/src/lib.rs b/crates/libanalysis/src/lib.rs
index 19b64fece..a50a0f32f 100644
--- a/crates/libanalysis/src/lib.rs
+++ b/crates/libanalysis/src/lib.rs
@@ -163,15 +163,21 @@ impl World {
             Some(name) => name.text(),
             None => return Vec::new(),
         };
-        let id = match self.resolve_relative_path(id, &PathBuf::from(format!("../{}.rs", name))) {
-            Some(id) => id,
-            None => return Vec::new(),
-        };
-        vec![(id, FileSymbol {
-            name: name.clone(),
-            node_range: TextRange::offset_len(0.into(), 0.into()),
-            kind: MODULE,
-        })]
+        let paths = &[
+            PathBuf::from(format!("../{}.rs", name)),
+            PathBuf::from(format!("../{}/mod.rs", name)),
+        ];
+        paths.iter()
+            .filter_map(|path| self.resolve_relative_path(id, path))
+            .map(|id| {
+                let symbol = FileSymbol {
+                    name: name.clone(),
+                    node_range: TextRange::offset_len(0.into(), 0.into()),
+                    kind: MODULE,
+                };
+                (id, symbol)
+            })
+            .collect()
     }
 
     fn resolve_relative_path(&self, id: FileId, path: &Path) -> Option<FileId> {
diff --git a/crates/libanalysis/tests/tests.rs b/crates/libanalysis/tests/tests.rs
new file mode 100644
index 000000000..9ef5200af
--- /dev/null
+++ b/crates/libanalysis/tests/tests.rs
@@ -0,0 +1,45 @@
+extern crate libanalysis;
+extern crate assert_eq_text;
+
+use std::path::PathBuf;
+
+use libanalysis::{WorldState, FileId};
+use assert_eq_text::assert_eq_dbg;
+
+
+#[test]
+fn test_resolve_module() {
+    let mut world = WorldState::new();
+    world.change_file(FileId(1), Some("mod foo;".to_string()));
+    world.change_file(FileId(2), Some("".to_string()));
+
+    let snap = world.snapshot(|id, path| {
+        assert_eq!(id, FileId(1));
+        if path == PathBuf::from("../foo/mod.rs") {
+            return None;
+        }
+        assert_eq!(path, PathBuf::from("../foo.rs"));
+        Some(FileId(2))
+    });
+    let symbols = snap.approximately_resolve_symbol(FileId(1), 4.into())
+        .unwrap();
+    assert_eq_dbg(
+        r#"[(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]"#,
+        &symbols,
+    );
+
+    let snap = world.snapshot(|id, path| {
+        assert_eq!(id, FileId(1));
+        if path == PathBuf::from("../foo.rs") {
+            return None;
+        }
+        assert_eq!(path, PathBuf::from("../foo/mod.rs"));
+        Some(FileId(2))
+    });
+    let symbols = snap.approximately_resolve_symbol(FileId(1), 4.into())
+        .unwrap();
+    assert_eq_dbg(
+        r#"[(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]"#,
+        &symbols,
+    );
+}