Code review comment for lp:~abentley/launchpad/fix-undiverging

Diverged messages should be very rare except as a remnant of pre-sharing data. So by far most messages should not have been associated with a specific template; they will be shared between templates. It's an interesting thought to keep that information around, but currently we don't. We do keep some information about where a message comes from, of course: the project or source package as well as the translator and reviewer.

It's true that the situation with factory methods isn't ideal. Translation messages can be suggestions; shared; or diverged. Yet we have three methods for making, respectively, suggestions; lots of different kinds of messages; or diverged messages. This is largely an artifact of our transition to the Recife model. We used to have a dedicated factory method for making shared messages. I think the cleaner way would be to leave the option for creating diverged messages out of makeCurrentTranslationMessage (taking away a code path and a parameter) and perhaps renaming it makeSharedTranslationMessage. Swiss-army-knife methods with parameters to select different, possibly conflicting operating modes are something we're trying to get away from.