How to delete all remote git branches which have already been integrated?

Question

At work we are using topic branches which are integrated into a few (3) master branches at some point. Now I'd like to delete all topic branches from my remote repository which have been fully integrated into a master branch. If that's not possible, retrieving a list of local branches which have been integrated would be fine, too.

Answer 1

Another answer edited in by someone who thought it's the best (and it looks good):

git branch -r --merged origin/master | grep -v master | grep "origin/" | cut -d "/" -f 2- | xargs -n 20 git push --delete origin 

Explanation:

• git branch -r --merged origin/master
  • -r/--remotes list the remote-tracking branches.
  • --merged origin/master only list branches whose tips are reachable from origin/master.
• grep -v master remove any branch name containing master from list.¹-v means negative match.
• grep "origin/" select only branches on origin remote.
• cut -d "/" -f 2- drop the origin/ prefix
• xargs -n 20 git push --delete origin do something similar to git push --delete origin branch-a branch-b branch-c …
  • -n 20/--max-args=20 use at most 20 arguments per command line.

As for -n, I choose 20 just as an example. Fewer arguments will make it slower, for example -n 1 makes it delete one at a time; you have more progress hints, because it will report each time it deletes a branch. More arguments like -n 200 will make it faster (less total time), but it only reports once every 200 branches, making you think that it is frozen at first (while it is not). Tune the number to your need. If you omit this option, the default number is really large (2048 in my machine).

_{1. Note that this also removes origin/HEAD -> origin/master, but you won't want to mess with origin/HEAD anyway.}

Original answer:

git push --delete remote topicbranch 

or

git push remote :topicbranch 

Giving a list of branches, would be something with git branch --merged master