Src not working as expected

I wanted to list of all files from specific branch.

So I did following 

```
$client->repositories()
            ->workspaces('abc')
            ->src('xyz')
            ->show('demo',"/");
```
**demo** is my branch name

Above code should return list of files as per documentation but it is not working.

Can you please help me out how can I get list of files? 