Data Engine datasource scanner fails for branches with '/' in name

[mcbeaker]

The Data Engine datasource scanner returns 0 files for repository-type datasources when the branch name contains a / character (e.g.,
feature/my-branch). The same datasource path works correctly when using a branch without /.

Reproduction Steps

1. Create two branches from the same commit:

   • test/slash-branch (with /)
   • test-no-slash (without /)

2. Create datasources pointing to the same DVC-tracked path on each
   branch:

   from dagshub.data_engine.datasources import create_datasource            
                                                                            
   # Branch WITH slash                                                      
   ds_slash = create_datasource(                                            
       repo='<owner>/<repo>',                                               
       name='test-with-slash',                                              
       path='data/my-folder',                                               
       revision='test/slash-branch'                                         
   )                                                                        
                                                                            
   # Branch WITHOUT slash                                                   
   ds_no_slash = create_datasource(                                         
       repo='<owner>/<repo>',                                               
       name='test-without-slash',                                           
       path='data/my-folder',                                               
       revision='test-no-slash'                                             
   )                                                                        

3. Wait for scanner to complete and check results:

   from dagshub.data_engine import datasources                              
                                                                            
   ds_slash = datasources.get_datasource('<owner>/<repo>',  'test-with-slash')                                                          
   ds_no_slash = datasources.get_datasource('<owner>/<repo>', 'test-without-slash')                                                       
                                                                            
   print(f'test/slash-branch: {len(ds_slash.all())} files')                 
   print(f'test-no-slash: {len(ds_no_slash.all())} files')                  

Expected Behavior

Both datasources should return the same file count (the actual count in
that directory).

Actual Behavior

Branch	Files Found
test/slash-branch	0
test-no-slash	100

Additional Evidence

Tested with multiple branch naming patterns:

Branch Name	Datasource Files
feature/add-events-ts-support	0
test/slash-branch	0
events-ts-test	100
test-no-slash	100

All branches point to the same commit with identical data.dvc and
.dvc/config.

Environment

• DVC remote: External S3 bucket connected to DagsHub
• Files are DVC-tracked and accessible via DagsHub content API (verified)
• Datasource type: REPOSITORY
• preprocessing_status: PreprocessingStatus.READY (scanner completes,
  just returns 0 files)

Workaround

Use branch names without / characters (e.g., feature-my-branch
instead of feature/my-branch).

[dagshub]

Join the discussion on DagsHub!

[guysmoilov]

Thank you for reporting the issue, we'll investigate