transposing and changePitch

[Stefan Thomas]

Dear community,
in the below quoted snippet the change-Pitch-command does not work as expected. It doesn't produce the second pitch one octave higher!
\version "2.12.2"
\include "changePitch.ly"
     brokenoctaves = #(define-music-function (parser location x) (ly:music?)
         #{
             $x \transpose c c' $x
         #})

test =   {  \brokenoctaves  c8  }
\new Staff {   \changePitch \test { c' } }