[Development] Qt6 repo

[Edward Welbourne]

Nibedit Dey (14 January 2021 22:18) wrote:
> Qt5 repo contains many branches and some have ambiguous names with
> respect to the Qt version. e.g: It is not clear whether the dev branch
> is applicable to Qt5 development or Qt6.

That ambiguity, at least, would go away if the module were called qt.git
instead of qt5.git; and we can easily do that, once we rename the old
qt.git to qt4.git (long over-due anyway), without affecting significant
numbers of people (Qt 4 is now history).

> We will wait for the Qt maintainers to take a call on this topic and
> let us know the decision.

Well, this mailing list *is* where and how the Qt maintainers make such
decisions, so let's have a concrete proposal (not new, just spelled out
here for the sake of concreteness):

* Rename the old qt.git to qt4.git
* Change anything that previously referenced qt.git to point to qt4.git
* Rename qt5.git to qt.git
* Retain a qt5.git symlink to qt.git on our public servers, so that
  those with checkouts using any of them as a remote (notably everyone's
  gerrit remote set up by init-repository) don't suffer disruption
* Change all instructions for how to work on Qt development to talk
  about the qt.git repo

The 5.* branches in qt.git will then obviously be the Qt 5 branches; the
6.* branches will equally obviously be the Qt 6 branches.  That dev is a
future Qt 6 version shall be a reasonable guess, although eventually dev
shall be the branch for Qt 7 development after we've released the last
Qt 6 minor; but that won't make much difference to a contributor, in any
case.  Once 7.* branches show up it'll be natural to suppose dev relates
to them, in the same way.

Then we have a simple qt.git as the super-repo for Qt, in all versions
after Qt 4, alongside the repositories for all the sub-modules that get
checked out under it, at least by the release team, notwithstanding that
some developers may be doing other things that better suit their own
workflows.

At some point in the distant future, we'll be able to delete the qt5.git
symlink, but we have no reason to to rush.

If we are feeling really paranoid, we can split the first two steps up
into

* Move qt.git to qt4.git, put in place a qt.git symlink pointing to it,
* Change all public mentions of qt.git to qt4.git
* Wait a month, remove symlink, wait a month

or insert some other time intervals in place of month, that suffice to
give a decent chance that anyone affected will trip over the change and
get their chance to catch up on what's happened, before qt.git changes
its meaning entirely.  But I doubt we need to be this paranoid.

All discussion of *what* resides in qt.git, including whether to break
out the Coin provisioning stuff to another module, is separate from this
so can be handled as a separate discussion (please change Subject).

	Eddy.