counter.set(23)
        def unpackedValue = provider.get()

        then:
        unpackedValue == 46
        // Side effect of the provider returned by transform is executed first.
        // See FlatMapProvider for details
        1 * sideEffect2.execute(46)

        then: // ensure invocation order
        1 * sideEffect1.execute(23)
        0 * _

        when:
        unpackedValue = provider.get()