snapcraft copies /etc/apt/sources but ignores /etc/apt/preferences

[Albert Astals Cid]

This means that if you have a somewhat complex setup, you will end up with snapcraft getting the wrong packages since the preferences file will be ignored

[Leo Arias (elopio)]

Thanks for the report Albert. Can you please add some steps to reproduce the problem?

[Albert Astals Cid (aacid)]

Step 1: Be on zesty
Step 2: Add yakkety to your apt/sources.list
  i.e. i added
    deb http://bouyguestelecom.ubuntu.lafibre.info/ubuntu/ yakkety main restricted universe multiverse
Step 3: Have this preferences file http://paste.ubuntu.com/23445636/

This means that now if you apt-get install vim on a system were it was previously uninstalled, version 7.4.1829-1ubuntu2 from yakkety will be installed instead of version 7.4.1829-1ubuntu4 from zesty even if zesty one is newer.

Now if you make a snap that wants to package vim, since the preferences file is ignored the zesty version will be picked up.

Now imagine that instead of vim it's a library and for some weird reason my snap depends on an old version or something.