706391 - Figure out branching mechanics to keep 2.1.x safe from the playground

Status: RESOLVED INCOMPLETE

(Camino Graveyard :: General, defect)

Description

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

Stuart and I talked in the channel today about branching in order to keep his playground work from breaking 2.1.x while also allowing the code to be committed somewhere public (regardless of what the future holds).

I initially thought of the MozHg idea of branching, which is to set up an entirely new repo for 2.1.x, e.g. releases/camino-2.1, and all the associated bits (Socorro integration, MXR, tinderbox configs, etc.).  It's a bit heavy-weight and relies on a bunch of MoCo departments making changes to their systems and then deploying them, which will take some time once I get the time to start driving them.

Stuart suggested as a lighter-weight alternative of forking the code on googlecode; the disadvantages are, well, it's a fork; it would be more difficult to get builds and much more difficult to get ancillary things like MXR (and no, Google Code Search doesn't cut it :P ).

The other thing I thought of tonight is, since Camino isn't enormous like Gecko, why not use Hg's built-in branches, which are another lighter-weight solution?  The advantages: no need for IT to create a repo and no need to beg Socorro folks to add a new repo to config and deploy so that we still get source lines and links for 2.1.x crashes (I'd need to think the Socorro part through carefully when not tired, but I think it'd "just work" for both branches).  Builds would be fairly simple (although I'd need to check and make sure madhatter supports pull-by-branch, but that shouldn't be hard to add if it doesn't work yet).  MXR for 2.1.x wouldn't work out of the box (though we could probably get someone to make it work), but we didn't have MXR for 1.5.x or 2.0.x, either, and crash reports would link us to the right revisions on hgweb.  Also, for those of us who would be working on both 2.1.x and 2.1+, I believe we can have local clones with hard links, so that we only have one checkout (.hg) taking up space but could still have a separate working copy for each branch.

We should think some more about this and check out our facts to be sure, but I'm leaning towards a true Mercurial branch right now…

Comment 1

[Stuart Morgan]

As described, that SGTM :)

Comment 2

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

FWIW, I added support to madhatter today that should allow us to specify different tags/branches for each repo, which was going to be needed here so that Cm2.1.x could pull a different branchname for hg.m.o/camino than for Gecko: http://hg.mozilla.org/users/alqahira_ardisson.org/madhatter/rev/bf5bfee0d0de