Return an error for queries with invalid, named selectors

[dominiklohmann]

Bug report

When querying with an invalid, named selector, yabai acts as if no selector was given at all and returns the focused window/space/display. When given a number instead of a string, yabai returns an error instead.

# returns an error

❯ yabai -m query --windows --window 0
could not locate the selected window.
❯ echo $?
1

# returns the focused window

❯ yabai -m query --window --window asdf
{ ... }
❯ echo $?
0

The behaviour should be consistent so that scripts can test whether a valid selector was provided.

# check if a valid display selector was provided by the user
if ! yabai -m query --displays --display "${1}" > /dev/null 2>&1; then
        >&2 echo "could not locate the selected display."
        exit 1
fi

[koekeishiya]

Fixed on master.