bug#20357: 25.0.50; deactivate-mark behavior broken

[Stefan Monnier]

> (with-temp-buffer
>   (insert "foobar")
>   (set-mark (point))
>   (goto-char (point-min))
>   (indent-region (point-min)
>                  (point-max))
>   mark-active)
> In 24.5 it returns nil, which is correct. While in 25 it returns t.

Why is it more correct to return nil than to return t?

> This is a recent change, 24.5.2 doesn't have this bug.
>
> (let (deactivate-mark)
>   (indent-region (region-beginning)
>                  (region-end)))
>
> Expected behavior: the mark isn't deactivated.

At least in 24.4, the mark does get deactivated in my test.


        Stefan