Junio C Hamano [off-list ref] writes:

Junio C Hamano [off-list ref] writes:

quoted

 * I would have preferred to see the early parts of the series all
   being opt-in, and that subset of the series be able to graduate
   earlier.  Way earlier than the default flip to prove that they do
   not hurt when unconfigured (they are theoretically no-op while
   being opt-in, but we want to make sure), and that they do help
   when configured.  And then once we are satisfied, the default
   flip can be discussed and applied.

Thinking about this a bit more, I see a strong reason to prefer the
way the series in this iteration is constructed.  We could merge the
early parts down to 'next' well before the last piece, and hopefully
we will know how much what they are already using breaks (and we
know colors are use in the field, and we know by default we pass
colors, so this is to catch other uses of control sequences) by
filtering among those who are running 'next' for their every-day
work, before the main part of the series leaves 'master'.

If we did it the other way around, even if we mergee everything to
'next', the guinea-pig population will be limited to those who build
'next' with WITH_BREAKING_CHANGES, which would be a lot smaller
minority (I suspect that nobody uses a build with
WITH_BREAKING_CHANGES for their every-day work, actually).

So I no longer think the "no-op by default first and then tighten at
the end with WITH_BREAKING_CHANGES" is my preference.

The other two points I still care about.

Others have any opinion on the topic?