2 files changed, 10 insertions, 8 deletions

diff --git a/crates/vfs/src/file_set.rs b/crates/vfs/src/file_set.rs
index 0173f7464..d0ddeafe7 100644
--- a/crates/vfs/src/file_set.rs
+++ b/crates/vfs/src/file_set.rs
@@ -18,7 +18,7 @@ impl FileSet {
     pub fn resolve_path(&self, anchor: FileId, path: &str) -> Option<FileId> {
         let mut base = self.paths[&anchor].clone();
         base.pop();
-        let path = base.join(path);
+        let path = base.join(path)?;
         let res = self.files.get(&path).copied();
         res
     }
diff --git a/crates/vfs/src/vfs_path.rs b/crates/vfs/src/vfs_path.rs
index 940f91d0e..dc3031ada 100644
--- a/crates/vfs/src/vfs_path.rs
+++ b/crates/vfs/src/vfs_path.rs
@@ -22,15 +22,15 @@ impl VfsPath {
             VfsPathRepr::VirtualPath(_) => None,
         }
     }
-    pub fn join(&self, path: &str) -> VfsPath {
+    pub fn join(&self, path: &str) -> Option<VfsPath> {
         match &self.0 {
             VfsPathRepr::PathBuf(it) => {
                 let res = it.join(path).normalize();
-                VfsPath(VfsPathRepr::PathBuf(res))
+                Some(VfsPath(VfsPathRepr::PathBuf(res)))
             }
             VfsPathRepr::VirtualPath(it) => {
-                let res = it.join(path);
-                VfsPath(VfsPathRepr::VirtualPath(res))
+                let res = it.join(path)?;
+                Some(VfsPath(VfsPathRepr::VirtualPath(res)))
             }
         }
     }
@@ -101,13 +101,15 @@ impl VirtualPath {
         self.0 = self.0[..pos].to_string();
         true
     }
-    fn join(&self, mut path: &str) -> VirtualPath {
+    fn join(&self, mut path: &str) -> Option<VirtualPath> {
         let mut res = self.clone();
         while path.starts_with("../") {
-            assert!(res.pop());
+            if !res.pop() {
+                return None;
+            }
             path = &path["../".len()..]
         }
         res.0 = format!("{}/{}", res.0, path);
-        res
+        Some(res)
     }
 }