Document possibly backwards-incompatible localflavor changes

[Kyle Fox]

It appears the regression tests were not updated as part of ​changeset 14195

This patch changes the regression test to use the new provinces in the ID localflavor.

[Karen Tracey]

See comment at the end of ​http://code.djangoproject.com/ticket/13830#comment:4. I don't think changing the 3-letter code is safe at this point. I think the correct fix here is to restore the old 3-letter code and fix the test to recognize the new human-readable name only.

[Alex Gaynor]

I seem to recall we had this issue before, anyone good at search or remember the result?

[Russell Keith-Magee]

Following discussion on IRC with Karen, Alex, Ramiro, SmileyChris and myself:

There is a backwards compatibility issue here, and we can't ignore it. However, by the same token, maintaining displayable lists that contain invalid data (i.e., deprecated, renamed and dissolved provinces) is equally bad.

So - here's the plan:

• We will document our policy that as a project, we will maintain alignment with officially gazetted municipality lists. If Indonesia deprecates the name, so do we in the next major release, and if an official abbreviation has changed, we'll reflect that change too.
• We *won't* backport any such change to the stable branch. Micro releases shouldn't affect display/behavior, or require any data migration.
• When we introduce such a change, we will include it in the release notes as a noteworthy backwards compatibility issue.
• We will provide a new documentation page that will provide any script/SQL/utility/example that might help with migration process.
• For the affected release, the module in question will raise a Warning. This ensures that anyone that uses the module and doesn't read the release notes will get notified that there is a problem that needs to be resolved.
• We will provide a section in the localflavor docs telling people how to silence the warning once they've addressed the issue.

[Honza Král]

Ignorant about this ticket I commited a fix for the tests alone in r14249. There are still issues, as outlined by russelm above this, that need to be resolved.

[Karen Tracey]

Change summary to reflect what this ticket is now about. The changes include both the changeset identified here, and r12985 (somewhat belated at this point, but it should still be done).

Also the backport of this Indonesian change (r14196) to the 1.2.X branch should be reverted, along with any test changeset made to fix the test issue (though that does not seem to have been backported yet?), since we have decided it is best not to backport these types of things.

[Russell Keith-Magee]

(In [14410]) [1.2.X] Reverted r14196, restoring the 1.2 test suite to a passing state. Refs #14455.

[Russell Keith-Magee]

(In [14411]) Fixed #14455 -- Documented the backwards compatibility policy for local flavors. Implemented the policy for the changes in the Indonesian local flavor (from r14195) that stimulated the development of this policy. Thanks to Karen, Alex, Ramiro and Chris for their help developing the policy.

[Russell Keith-Magee]

For the record, r14195 was reverted in r14410.

[Jacob]

Milestone 1.3 deleted