looks like in-target doesn't echo output on stdout and thus the test command fails
Jun 24 17:48:37 debconf: --> GET debian-installer/locale Jun 24 17:48:37 debconf: <-- 0 en_US.UTF-8 Jun 24 17:48:37 in-target: Reading package lists... Jun 24 17:48:37 in-target: Jun 24 17:48:37 in-target: Building dependency tree... Jun 24 17:48:38 in-target: Jun 24 17:48:38 in-target: Reading state information... Jun 24 17:48:38 in-target: Jun 24 17:48:38 in-target: lsb-release is already the newest version. Jun 24 17:48:38 in-target: lsb-release set to manually installed. Jun 24 17:48:38 in-target: 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. Jun 24 17:48:38 log-output: + in-target lsb_release -c -s Jun 24 17:48:38 debconf: --> GET mirror/protocol Jun 24 17:48:38 debconf: <-- 0 http Jun 24 17:48:38 debconf: --> GET mirror/http/proxy Jun 24 17:48:38 debconf: <-- 0 http://webproxy.eqiad.wmnet:8080 Jun 24 17:48:38 debconf: --> GET debconf/priority Jun 24 17:48:38 debconf: <-- 0 high Jun 24 17:48:38 debconf: --> GET debian-installer/locale Jun 24 17:48:38 debconf: <-- 0 en_US.UTF-8 Jun 24 17:48:38 in-target: jessie Jun 24 17:48:38 log-output: + [ = jessie ] Jun 24 17:48:38 log-output: sh: jessie: unknown operand Jun 24 17:48:38 debconf: --> PROGRESS STEP 1 Jun 24 17:48:38 debconf: <-- 0 OK Jun 24 17:48:38 debconf: --> PROGRESS INFO finish-install/progress/speakup Jun 24 17:48:38 debconf: <-- 10 finish-install/progress/speakup does not exist Jun 24 17:48:38 debconf: --> SUBST finish-install/progress/fallback SCRIPT speakup