def on_no_matching_projects(worktree, groups=None):
    if groups and len(groups) > 1:
        mess = """The groups {groups} do not contain any project in the worktree {worktree.root}."""
    elif groups and len(groups) == 1:
        groups = groups[0]
        mess = """The group {groups} does not contain any project in the worktree {worktree.root}."""
    else:
        mess = """The worktree in {worktree.root}
does not contain any project."""
    tips = """
Tips:
    * Use `qisrc init` to fetch some sources from a remote manifest
    * Use `qisrc add` to register a new project path to this worktree
"""
    ui.warning(mess.format(worktree=worktree, groups=groups) + tips)
What to do when we find an empty worktree
dataset/ETHPy150Open aldebaran/qibuild/python/qisrc/worktree.py/on_no_matching_projects