diff --git a/extensions/ql-vscode/src/common/file-tree-nodes.ts b/extensions/ql-vscode/src/common/file-tree-nodes.ts
index 32144c885d7..3544265ca58 100644
--- a/extensions/ql-vscode/src/common/file-tree-nodes.ts
+++ b/extensions/ql-vscode/src/common/file-tree-nodes.ts
@@ -41,6 +41,9 @@ export class FileTreeDirectory extends FileTreeNode {
   }
 
   public createDirectory(relativePath: string): FileTreeDirectory {
+    if (relativePath === ".") {
+      return this;
+    }
     const dirName = dirname(relativePath);
     if (dirName === ".") {
       return this.createChildDirectory(relativePath);