TODO:

  1. make sure dummy names are clear
  2. put links to the new dev guide, etc.

Abstract

Here are some tentative workflow and naming conventions developed at Sage Days 54, together with some FAQs about using git.

Rationale

First-time setup

Talk about a sample ~/.gitconfig. Talk about a sample $SAGE_ROOT/.git/config.

git remote set-url origin [email protected]:sage.git

Basic git commands

If you have a local branch on your personal computer that you would like to push to trac, there are three options:

$ git push --set-upstream origin <mybranch>:u/<mytracname>/<mybranch>
$ git push --set-upstream origin <mybranch>:public/combinat/<mybranch>
$ git push --set-upstream origin <mybranch>:public/ticket/<ticketnumber>-<mybranch>

You would use the first one for code you personally work on. The second option is for collaborative code with other combinat people. If you already have a ticket number, use

$ git push --set-upstream origin <mybranch>:public/combinat/<ticketnumber>-<mybranch>

The third option is for tickets unrelated to combinat.

The first time you pull a branch from trac onto your local computer (in the example you are pulling a branch called 10305-partition and are calling it <mybranch>; usually it might be good to use the same name):

$ git remote update origin
$ git checkout -b <mybranch> origin/public/ticket/10305-partition

After the initial pull or push, this is the workflow to push your local changes to trac:

$ git checkout <mybranch>
$ git pull --ff-only
$ git push

The option --ff-only for the pull command makes sure that if there are big merge conflicts with the new changes on trac, you can handle them manually without messing up your entire branch and your local changes. If there are big changes, you can use these commands:

$ git checkout <mybranch>
$ git pull --ff-only
*git complains*
$ git fetch
$ git merge FETCH_HEAD
...
*resolve any merge conflicts*
*or give up and say: "git merge --abort"*
...
$ git status
...
*some output???*
...
$ git commit -a -m '<some message>'
$ git push

Getting the latest version of Sage

$ git checkout master
$ git pull --ff-only

If you want to delete a branch:

$ git checkout <somethingelse>
$ git branch -d <mybranch>

This might complain if you are trying to delete a branch that has not been merged yet. If nonetheless you would like to delete it, try a hard delete:

$ git branch -D <mybranch>

Even in a hard delete this can be undone in the next 30 days (before the commits get garbage collected).

To delete a remote branch:

$ git push origin :u/aschilling/<something>

If you accidentally edited master and want to undo your change

$ git branch -m master <mybranch>
$ git branch master origin/master

If you do not care about the changes you can do a hard reset

$ git reset --hard origin/master

Accidentally work on master, want to save it: git branch -m master mybranch git branch master origin/master

git checkout -b combinat/kschur master

Branch naming conventions

mystuff

u/aschilling/mystuff

public/combinat/mystuff

public/combinat/10305-partition-tableaux

Consistently using these naming conventions among all (sage-combinat) developers will make it easier to search for stuff. For example, trying to find all branches related to combinatorics can be found as follows

$ git ls-remote origin '*combinat*'
5feebdbfa73f64dafe28a5e4fe0144ab36083ab0        refs/heads/public/combinat/15361-branching-rules
7f974aeb3446206c029ac047c31938d55d86e651        refs/heads/u/aschilling/combinat/kschur

If you want to see what a specific author did on trac within the last day, you do

$ git remote update origin
$ git log --all --author="Bump" --since=1.day
commit 5feebdbfa73f64dafe28a5e4fe0144ab36083ab0
Author: Daniel Bump <[email protected]>
Date:   Wed Nov 6 09:51:08 2013 -0800

    get_branching_rule for F4=>B3 and G2=>A1 should return vectors of the correct length

Checking how the ticket branches of author mguaypaq differ from main sage (or origin/master) try

$ git log --remotes='origin/u/mguaypaq/ticket/*' ^origin/master --oneline
1c7458a #15300: Implement Weyl and Clifford algebras.
fb33147 Merge branch 'master' into ticket/10305
405178b Remove extra chunk from farahat_higman.py and fix related formatting issues.
25ff1fd Split off SymmetricGroupAlgebraCenter to its own file.
9b72574 Add rings for the center of the symmetric group algebras.

Example workflow

Moving a ticket from patches to git

Moving a patch from the combinat queue to git

All patches in the queue will soon be merged from the sage-combinat queue to git branches on trac. Authors who want to do this themselves are encouraged to do so. The script will by default put the branches to public/combinat/branchname and might loose author information if the patch does not have the appropriate meta information.

Here is a sample workflow on how to transform your patch to git:

$ git checkout -b combinat/kschur master
$ git branch
* combinat/kschur
  master
  ticket/15300

$ sage --dev import-patch --local-file /Applications/sage-5.13.beta2/devel/sage-combinat/.hg/patches/kschur-as.patch

$ git push --set-upstream origin combinat/kschur:u/aschilling/combinat/kschur
Counting objects: 47, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (7/7), done.
Writing objects: 100% (7/7), 1.27 KiB | 0 bytes/s, done.
Total 7 (delta 6), reused 0 (delta 0)
To [email protected]:sage.git
 * [new branch]      combinat/kschur -> u/aschilling/combinat/kschur
Branch combinat/kschur set up to track remote branch u/aschilling/combinat/kschur from origin.

kschur-as.patch

kschur-as.patch # git:u/aschilling/combinat/kschur

References