prepares github pull request with full clean view of the selected files

pull-request-prepare.rb

#!/usr/bin/env ruby

# prepares github pull request with full clean view of the selected files
# to run it
#  * delete some files after commit that is pushed, and leave them unstaged
#  * pull-request-prepare.rb will
#    * create branch-review-start with all marked files deleted
#    * create branch-review-end with all marked files re-added
#    * leave starting branch untouched
#    * open github url for pull request

require 'slop'
require 'colorize'

module Sys
  extend self

  def die data=nil
    puts data.red if data
    yield if block_given?
    exit
  end

  def run command
    puts command.blue
    system "#{command} 2>&1"
  end

  def open command
    system "open '%s'" % command
  end
end

class PullRequest
  def initialize(opts)
    # define vars
    @opts                = opts
    @files               = `git ls-files -m`.chomp.split($/)
    @current_branch      = `git rev-parse --abbrev-ref HEAD`.to_s.chomp.sub(/\*\s/,'')
    @currenct_hash       = `git rev-parse HEAD`.chomp
    @branch_suffix       = opts[:hash] ? @currenct_hash[0,7] : @current_branch
    @review_branch_start = 'review-%s-start' % @branch_suffix
    @review_branch_end   = 'review-%s-end'   % @branch_suffix
  end

  def clean_branches
    Sys.run 'git push origin --delete %s' % @review_branch_start
    Sys.run 'git push origin --delete %s' % @review_branch_end
    Sys.run 'git branch -D %s'            % @review_branch_start
    Sys.run 'git branch -D %s'            % @review_branch_end
  end

  def execute
    if @opts[:execute]
      Sys.die 'To define files that need review, delete or modify them.' if @files.length == 0

      # can't be in review branch when executing
      Sys.die 'Current branch cant be review branch (%s)' % @current_branch if @current_branch.index('-review')

      prepare
      prepare_start_branch
      prepare_end_branch
      push_and_finish
    elsif [:update]
      #   git diff review-master-start..review-master-end --name-only

    end
  end

  def prepare
    # revert to state before deletion of files and prepare branches
    Sys.run 'git reset --mixed'

    clean_branches
  end

  def prepare_start_branch
    Sys.run 'git checkout -b %s' % @review_branch_start

    # remove files in start review branch
    @files.each { |file| Sys.run 'rm %s' % file }

    # and commit changes
    Sys.run "git add -A && git commit -m 'review start'"
  end

  def prepare_end_branch
    Sys.run 'git checkout -b %s' % @review_branch_end

    # re-add files in end review branch
    @files.each { |file| Sys.run "git checkout %s '%s'" % [@current_branch, file] }

    Sys.run "git add -A && git commit -m 'review end for %d files'" % @files.length
  end

  def push_and_finish
    Sys.run 'git checkout %s' % @current_branch

    Sys.run 'git push origin %s' % @review_branch_start
    Sys.run 'git push origin %s' % @review_branch_end

    Sys.run 'git reset %s --hard' % @currenct_hash
  end

  def open_url
    url_parts = `git remote -v | grep origin`.split(/[\s:]/)
    domain    = url_parts[1].split('@').last
    path      = url_parts[2].sub('.git', '')

    case domain
      when 'bitbucket.org'
        Sys.open 'https://bitbucket.org/dino_reic/raum-dog/pull-requests/new?source=%s&t=1#diff' % @review_branch_end
      when 'github.com'
        Sys.open 'https://github.com/%s/compare/%s...%s' % [path, @review_branch_start, @review_branch_end]
      else
        Sys.die 'Unsuported url for domain %s' % domain
    end

  end
end

###

opts = Slop.parse do |o|
  o.bool '-x', '--execute', 'execute the creation of pull request'
  o.bool '-u', '--update', 'update end branch with changed files'
  o.bool '-c', '--clean',   'clean all branches and exit'
  o.bool '-h', '--hash',    'hash branch name to make it unique'
  o.bool '-o', '--open',    'open github url'
end

Sys.die { puts opts } unless ARGV[0]

pr = PullRequest.new opts

opts.clean? && Sys.die { pr.clean_branches }
pr.execute if opts.execute? || opts.update?
opts.open? && pr.open_url