Rule:

codeowners(
    name = "my_team",
    patterns = [
        "/application-a/",
        "/application-b/",
    ],
    teams = [
        "@tink-ab/my-team",
    ],
)

I just had a case where I removed all files in the application-a, including the directory. However, the generate_codeowners(...) target happily executed. It would nice if it would have failed telling me that I should removed patterns not patching anything (and possibly support disabling this check if files can be checked in dynamically or something).