def "supplies no installations for non-existing directory"(boolean useProperty) {
        assert mavenHome.delete()

        given:
        def supplier = useProperty ? createSupplier(mavenHome.getCanonicalPath(), null) : createSupplier(null, userHome)

        when:
        def directories = supplier.get()

        then:
        directories.isEmpty()

        where:
        useProperty << [true, false]
    }