[RFC] rename repository branches

[thaJeztah]

Description

Relates to

• [Docker Compose] V2 GA roadmap#256
• [Docker Compose] V1 End of Life Policy roadmap#257

When development for Compose v2 (reimplementation in Go) moved to this repository, the master branch (in which the code for the (now in "maintenance mode") Python implementation lives, was kept, and a new v2 branch was created and set as default branch.

Now that v2 is GA, and the default, we should consider:

• renaming the old (python) branch from master to v1
• renaming the (default) v2 branch to main

Opening this, as I have to fight muscle-memory every time I want to contribute to this repository 😂, and I can expect new contributors to this repository to also run into this (and possibly get confused).

⚠️ ❓ For go modules, renaming the branch should have no immediate consequences (unless someone does a go get github.com/docker/compose/v2@v2 to explicitly include the branch name), but I don't know if renaming the branch would have consequences for Python (don't think so?)

[thaJeztah]

/cc @ndeloof @milas @glours

[glours]

Hey @thaJeztah 👋

We didn't communicate publicly on this, but this exactly what we decided.
We can keep your issue open to let users know what will happen next April

[thaJeztah]

Ah, cool! Wonder if this must be done together with the deprecation, or if we could already do this (I think it should be generally non-disruptive, so perhaps there's no need to wait).

[laurazard]

Agreed! Would be nice to do this sooner rather than later. At first glance, I don't think anything would happen (any system automatically getting compose should be using the release URLs such as https://github.com/docker/compose/releases/download/.../... which stay the same). We can try to investigate a little bit just to make sure.

[thaJeztah]

One warning; there was (or is?) a bug on GitHub, where renaming the branch does not update PRs that were opened from the web-ui (edit-button on GitHub). That workflow is probably less common on this repository as it is for the docs repository, but something to be aware of; see moby/mobywebsite#69 (comment) and docker/docs#14540 (comment)

[ndeloof]

closing as done