-- in.cue --
service: [ID=string]: {
    ports: [...{
        protocol: *"TCP" | "UDP"
        extra: 3
    }]
}

service: a: {
    ports: [{
        name:     "a"
        protocol: "TCP"
        key: "bar"
    }]
}

service: a: {
    ports: [{
        protocol: "TCP"
        key: "bar"
    }]
}

service: a: {
    ports: [{
        extra: 3
    }]
}

-- out/trim --
== in.cue
service: [ID=string]: {
	ports: [...{
		protocol: *"TCP" | "UDP"
		extra:    3
	}]
}

service: a: {
	ports: [{
		name: "a"
		key:  "bar"
	}]
}

service: a: {
	ports: [{
		key: "bar"
	}]
}

service: a: {
	ports: [{
	}]
}