Minor We should add unit tests for nuxeo-document-tree to preserve it's functionality. We should test:
- Check that we can expand a Folderish document
- Check that icons have the correct orientation according to whether the document is expanded or not
- Check the the whole breadcrumb is present
- Check that clicking on a document collapses the three
- When we remove a document, the tree is updated
- When we create a document, the tree is update
- When refresh-display is fired, the tree is updated
