On Thursday, January 17, 2013 6:31:31 AM UTC+1, Jeenu wrote: > I wanted to find out names of downstream branches from a given current > branch, from the command line. I think there should be a way to find this, > as gitk already lists downstream branches. > > If I rebase subsystem branch S of master M, and all topic branches Tn > based on S would have be rebased again manually. For that it'd be helpful > to know all Tn given an S, without manual or visual examination. > > What's a downstream branch? And how do you list them with gitk?
Anyhow, I'll assume that you are asking how to get a list of all branches that have *the tip* of branch X as an ancestor. I'm not sure if this is what you actually want though. You can see all your local branches with `git branch`. Now you want for each of these, to see if X is included among their ancestors. Let's say they are A, B, C, while D is not an ancestor of X. The quickest way I can think of at the moment to check that (although there probably are more elegant ways), is to just check if the common ancestor of X and the branch in question: 1) git merge-base X A -> this outputs the SHA value of the common ancestor of A and X 2) git rev-parse A -> this outputs the SHA value of A 3) If the output of the two commands above are the same, then A is an ancestor of X. Or, to put it in bash: if [ `git merge-base X A` \=\= `git rev-parse A` ]; then echo "found ancestor"; fi 4) Repeat for all branches (or script it) Bear in mind that when A gets some more commits, the above doesn't work any more. You then have to find the common ancestor of A and X first, and see in which branches the ancestor is contained, maybe using git branch --contains. Interestingly enough, the docs on git branch<http://www.kernel.org/pub/software/scm/git/docs/git-branch.html>state this, which relates to your problem: --contains <commit> is used to find all branches which will need special attention if <commit> were to be rebased or amended, since those branches contain the specified <commit>. --
