pickaxe.rb

equire "rugged"

def diff_between_parent(commit)
  return if commit.parents.empty?
  parent = commit.parents.inject do |ret, item|
    commit.diff(ret).size < commit.diff(item).size ? ret : item
  end

  commit.diff(parent).each_patch do |patch|
    patch.each_hunk do |hunk|
      adds = hunk.lines.select(&:addition?)
      dels = hunk.lines.select(&:deletion?)
      if adds.size == 1 && dels.size == 1 && patch.delta.new_file[:path].start_with?("app/controllers")
        puts patch
        puts
      end
    end
  end

  diff_between_parent(parent)
end

repo = Rugged::Repository.new(".")
diff_between_parent(repo.last_commit)

equire