> > A possible gotcha in this approach is if there are any python 2/3 > incompatibilities that would not manifest as syntax errors or > obvious runtime errors, but would allow old code to execute and > silently do the wrong thing. One would hope that the Python crowd > weren't dumb enough to do that, but I don't know whether it's true. > If there are nasty cases like that, maybe what we have to do is allow > plpythonu/plpython2u functions to be dumped and reloaded into a > python-3-only install, but refuse to execute them until they've > been converted. >
Unfortunately, I think there are cases like that. The shift to Unicode as the default string means that some functions that used to return a `str` now return a `bytes` (I know of this in the hashlib and base64 modules, but probably also in URL request data and others), and to use a `bytes` in string manipulation you have to first explicitly convert it to some string encoding. So things like a function that wraps around a python crypto library would be the exact places where those was-str-now-bytes functions would be used.
