How to programmatically make a TreeView visible

I'm trying to make a TreeView visible programmatically. The TreeView is empty.

I tried to call TreeView.reveal with a dummy TreeNode but it remains not visible. The only other method available on TreeView is "dispose". I don't see how I can have access to the "container" of this treeview as it is created using vscode.window.createTreeView(...). I searched on vscode.window API but not found anything related to my purpose.

How can I reveal/make the TreeView visible programmatically?

fakeNode = new TreeNode("dummyType", "dummyLabel", "dummyStatus", vscode.TreeItemCollapsibleState.Expanded);
myTreeView.reveal(fakeNode); 
expect(myTreeView.visible).to.be.true