The bug is that cups-image is incorrectly marked as GENERALDEP instead of COMPILEDEP in core_installer.py. Note that it is already marked DEPENDENCY_COMPILE_TIME in field 3. Unfortunately that field is totally ignored in hplip (i.e. it is ripe for removal).
The bug is that cups-image is incorrectly marked as GENERALDEP instead of COMPILEDEP in core_installer.py. Note that it is already marked DEPENDENCY_ COMPILE_ TIME in field 3. Unfortunately that field is totally ignored in hplip (i.e. it is ripe for removal).
See the attached patch for a fix.