Hi,
I had an interesting afternoon yesterday, debugging test failures that happened while setting up the first layers. The error was not very helpful:
ValueError: _p_serial must be an 8-character bytes array
It turned out that due to a mistake, one package declared a dependency on persistent. Persistent is a package that has been extracted from ZODB3 3.10 to make living on its own. On its way there have been backward incompatible changes, that have haunted me here. I haunted me, because the way a tid is constructed changed slightly, and my tid was double quoted and causes this _p_serial error above.
I mention it as plone5 relevant because we have a version pinning for persistent in the coredev. Removing this is trivial, but then we use z3c.form 3.2.1 which has a test dependency on persistent. I am not sure what to make of that.
Should we pin an older version of z3c.form?
Should we try to remove this dependency on z3c.form upstream?
What is your opinion?