cherry-pick-all-branch-commits.rb

# DISCLAIMER: THE BELOW IS LESS-THAN-TERRIFIC RUBY. IT IS JUST SOMETHING I WHIPPED UP QUICKLY.

# This is a script for iterating over, in order of oldest to newest, all
# commits in all GitHub pull requests that were merged into a particular
# branch, and cherry-picking them onto the currently checked-out branch.
# It's useful for creating a copy of, say, a feature branch that was branched
# off a branch you did not want it to be, but that feature branch is too
# complex to simply rebase elsewhere.
#
# Usage:
#
# 1. You'll need to install the octokit and colorize gems first.
#
# gem install octokit
# gem install colorize
#
# I suppose you could also just add those gems to a Gemfile and
# use Bundler, but that's up to you.
#
# 2. Change the REPO and BRANCH_TO_CHERRY_PICK constants below.
#
# 3. Make sure you have the proper destination branch, the branch
# onto which you want to cherry-pick commits, checked out.
#
# 4. `ruby cherry-pick-all-branch-commits.rb`
#

require 'octokit'
require 'colorize'

# Change these to the values you need
REPO = 'foo/mooplex'
BRANCH_TO_CHERRY_PICK = 'my-amazing-feature-branch'

def branch_already_has_diff?(sha)
  system "git log | grep --quiet #{sha}"
end

def cherry_pick(commit)
  sha = commit[:sha]

  if branch_already_has_diff?(sha)
    puts "#{sha} already cherry-picked.".colorize(:yellow)
    true
  else
    puts "Cherry-picking commit #{sha}..."
    system "git cherry-pick -x #{sha}"
  end
end

def cherry_pick_all_commits_in_pull_request(pull_request)
  pull_request_number = pull_request[:number]
  puts "Cherry-picking commits from pull request ##{pull_request_number}, #{pull_request[:title]}...".colorize(:light_white)
  commits = @client.pull_request_commits(REPO, pull_request_number)

  all_commits_done = false
  for commit in commits
    all_commits_done = false
    break unless cherry_pick(commit)
    all_commits_done = true
  end

  all_commits_done
end

@client = Octokit::Client.new(netrc: true)

pull_requests = @client.pull_requests(REPO, state: 'closed', base: BRANCH_TO_CHERRY_PICK)

for pull_request in pull_requests.reverse
  break unless cherry_pick_all_commits_in_pull_request(pull_request)
  puts "Cherry-picking all commits from pull request ##{pull_request[:number]} succeeded.".colorize(:green)
end