min_num on formsets should not just be added to extra.

[Stephen Burrows]

The current implementation is slightly broken.

I would set min_num=3 if there should be at least three things. I would set extra=3 if I wanted three blank forms presented.

The implementation that was added in 1.7 means that there will *always* be six blank forms - initial data is *not* taken into account.
To put it another way, if min_num is 3, and extra is 2, and there is initial data for two forms, I would expect to have either 4 forms (2 extra on top of existing objects) or 5 forms (2 extra on top of the minimum.) With the code as it is, I will instead get seven forms - two for the existing objects, and an additional seven from extra.

See note on #9532.

(Is this a release blocker, since it's a bug in a new feature?)

[anonymous]

Pull request: ​ticket/22628

[Stephen Burrows]

^{Forgot to log in. :-p}

[Tim Graham <timograham@…>]

In 79f15ab1ef964c0209c4484ccf62ba458fd582b3:

[1.7.x] Fixed #22628 -- Took initial forms into account when combining FormSet.min_num and FormSet.extra.

[Tim Graham <timograham@…>]

In d64f192df188903ea5a1ab8dfd6679e5d52aaf9b:

Fixed #22628 -- Took initial forms into account when combining FormSet.min_num and FormSet.extra.

Forwardport of 79f15ab1ef from stable/1.7.x