Firefox Development Is Moving From Mercurial To Git

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glob

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Nov 6, 2023, 2:59:13 AM11/6/23
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FIREFOX DEVELOPMENT IS MOVING FROM MERCURIAL TO GIT

For a long time Firefox Desktop development has supported both Mercurial and
Git users. This dual SCM requirement places a significant burden on teams which
are already stretched thin in parts. We have made the decision to move Firefox
development to Git.

- We will continue to use Bugzilla, moz-phab, Phabricator, and Lando
- Although we'll be hosting the repository on GitHub, our contribution workflow
  will remain unchanged and we will not be accepting Pull Requests at this time
- We're still working through the planning stages, but we're expecting at least
  six months before the migration begins

APPROACH

In order to deliver gains into the hands of our engineers as early as possible,
the work will be split into two components: developer-facing first, followed by
piecemeal migration of backend infrastructure.

Phase One - Developer Facing

    We'll switch the primary repository from Mercurial to Git, at the same time
    removing support for Mercurial on developers' workstations.  At this point
    you'll need to use Git locally, and will continue to use moz-phab to submit
    patches for review.

    All changes will land on the Git repository, which will be unidirectionally
    synchronised into our existing Mercurial infrastructure.

Phase Two - Infrastructure

    Respective teams will work on migrating infrastructure that sits atop
    Mercurial to Git.  This will happen in an incremental manner rather than
    all at once.

    By the end of this phase we will have completely removed support of
    Mercurial from our infrastructure.


--
glob ∙ moz://a
Senior Engineering Manager ∙ Engineering Workflow & Release Management

Thomas Siebert

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Nov 7, 2023, 10:06:07 AM11/7/23
to firef...@mozilla.org, gl...@mozilla.com, dev-pl...@mozilla.org
Why is this decisions for Microsoft GitHub as a hoster?
Why not using a hoster with a open source git software like Gitea/Forgejo.
Why not using a privacy and free software respecting code hoster?

I would recommend Codeberg.org.

Lunny Xiao

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Nov 7, 2023, 9:38:10 PM11/7/23
to firef...@mozilla.org, gl...@mozilla.com, dev-pl...@mozilla.org
Maybe you can learn something from how blender move from Phabricator to self-hosted Gitea.

Sylvestre Ledru

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Nov 9, 2023, 12:17:34 PM11/9/23
to Thomas Siebert, firef...@mozilla.org, gl...@mozilla.com, dev-pl...@mozilla.org
Hello Thomas,

Mozilla has been using GitHub for a long time for many projects (ex: MDN, Firefox OS, Rust, Servo, VPN, etc).
We have a lot of experience maintaining projects on GitHub and it is well integrated in our systems.
By moving to a different platform, it would increase the fragmentation of our efforts.

Cheers,
Sylvestre

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Thomas Siebert

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Nov 10, 2023, 2:05:36 AM11/10/23
to Sylvestre Ledru, firef...@mozilla.org, gl...@mozilla.com, dev-pl...@mozilla.org
Am Do., 9. Nov. 2023 um 18:17 Uhr schrieb Sylvestre Ledru
<sylv...@mozilla.com>:
> Mozilla has been using GitHub for a long time for many projects (ex: MDN, Firefox OS, Rust, Servo, VPN, etc).
> We have a lot of experience maintaining projects on GitHub and it is well integrated in our systems.
> By moving to a different platform, it would increase the fragmentation of our efforts.

It would increase your freedom.
What you describe is that you are "locked-in" to Microsoft.
You have to start one day and can not stick to Microsoft.

And no matter if GitHub is drivin by Microsoft or by the 14th Dalai
Lama. GitHub is closed source.

Frederik Braun

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Nov 10, 2023, 4:30:02 AM11/10/23
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Am 10.11.23 um 08:05 schrieb Thomas Siebert:
It would increase your freedom.
What you describe is that you are "locked-in" to Microsoft.
You have to start one day and can not stick to Microsoft.

And no matter if GitHub is drivin by Microsoft or by the 14th Dalai
Lama. GitHub is closed source.

We are currently only moving repository hosting from hg.m.o to github. The original announcement specifically points out that we will continue to use bugzilla for issue tracking, phabricator for code reviews.

Mozilla has been using GitHub for over ten years now. Literally thousands of Mozilla repositories are already there. I personally believe that Git, as a decentralized technology, does not lock us in.

But I also want to point out that you are arguing at the time where a decision has been communicated, which is not the same as when a decision is still being made.

The Wanderer

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Nov 10, 2023, 7:17:45 AM11/10/23
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On 2023-11-10 at 04:29, Frederik Braun wrote:

> Am 10.11.23 um 08:05 schrieb Thomas Siebert:
>
>> It would increase your freedom. What you describe is that you are
>> "locked-in" to Microsoft. You have to start one day and can not
>> stick to Microsoft.
>>
>> And no matter if GitHub is drivin by Microsoft or by the 14th
>> Dalai Lama. GitHub is closed source.
>
> We are currently only moving repository hosting from hg.m.o to
> github. The original announcement specifically points out that we
> will continue to use bugzilla for issue tracking, phabricator for
> code reviews.

It also only barely mentions GitHub at all, among several references to
git - and does not mention any rationale for the choice to use GitHub
hosting, vs. another host or self-hosting. A switch to git(-only) in VCS
terms is one thing, and unless there are people with a strong preference
for Mercurial, is unlikely to be controversial; a move to GitHub as a
hosting platform is another, and given the opinions that exist about
both GitHub and its ownership, may well be controversial.

> Mozilla has been using GitHub for over ten years now. Literally
> thousands of Mozilla repositories are already there. I personally
> believe that Git, as a decentralized technology, does not lock us
> in.
>
> But I also want to point out that you are arguing at the time where a
> decision has been communicated, which is not the same as when a
> decision is still being made.

Was the possibility of the decision being made communicated prior to the
decision being made?

It is not reasonable to expect people to argue against a decision before
they become aware of it existing, and it is not reasonable to expect
people to be aware that a decision may be made before the possibility of
that decision being made has been communicated.

I do not currently read this mailing list on a more than superficial
level, but I do not remember seeing any previous announcement that a
move from Mercurial to git was being considered - much less that the
move would be to GitHub hosting (since git as a platform does not mean
GitHub as a host).

I've long held an opinion that communication in the Mozilla world
(and/or between that world and interested parties outside of it) leaves
something to be desired, and this looks to me like another example of
that pattern.


FWIW, I, too, am not in favor of the use of GitHub as a host -
especially not for a project of this scale and importance. One of the
primary points and advantages of git is - as you reference - its
decentralization; the apparent trend toward "all git projects are by
default expected to be hosted on GitHub" moves back towards
centralization again, with many or all of the disadvantages which that
brings, and the choice to put a project like this one there only
reinforces that undesirable trend.

(I wouldn't have brought it up if it weren't already being discussed,
however, since I've long since given up trying to convince Mozilla about
anything.)

--
The Wanderer

The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore all
progress depends on the unreasonable man. -- George Bernard Shaw

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