checkout_ticket.rb

#!/usr/bin/ruby

def prompt(message)
  STDOUT.write "#{message}: "
  STDIN.gets.strip
end

def error_and_exit!(error)
  $stderr.puts error
  exit(1)
end

def run
  issue_desc = ARGV[0]&.strip
  while issue_desc.nil?
    issue_desc = prompt "Enter ticket number or link"
  end
  number =
    if issue_desc.to_i.to_s == issue_desc
      issue_desc
    else
      matches = issue_desc.match(/QWEB-(\d+)/)

      if matches.nil?
        error_and_exit! "Couldn't parse issue number from '#{issue_desc}'"
      end
      matches[1]
    end

  puts "Searching for branch for #{number}..."
  issue = "qweb-" + number
  matching_branches = `git branch --list #{issue}*`.strip.split("\n")
  matching_branches = matching_branches.map { |branch_name| branch_name.gsub("*", "").strip }

  if matching_branches.count == 0
    puts "No matching branch. Checking out new one based on master..."
    checkout_result = system("git checkout master && git pull origin master")
    if !checkout_result
      error_and_exit! "Couldn't checkout and pull master."
    end
    branch_suffix = prompt "Please enter a descriptive suffix for the branch name (eg. 'do-something')"
    system("git checkout -b #{issue}-#{branch_suffix}")
    exit(0)
  else
    branch_name = nil
    loop do
      puts matching_branches.each_with_index.map { |branch_name, i| "\t#{i+1}. #{branch_name}" }.join("\n")
      branch_choice = prompt("Choose a branch to checkout").to_i
      branch_name = matching_branches[branch_choice - 1]
      if (1..matching_branches.length).cover?(branch_choice)
        system("git checkout #{branch_name}")
        exit(0)
      end
    end
  end
end

begin
  run
rescue Interrupt
  exit(1)
end