Git commits traveling through time

git-time-travel.rb

require 'git'
require 'logger'
require 'active_support/all'

g = Git.open(ENV['PWD'], :log => Logger.new(STDOUT))

g.log(100).each do |commit|
  actual = commit.author.date
  future = actual + 6.months
  %x(git filter-branch -f --commit-filter '
    if [ "$GIT_COMMIT" = "#{commit.sha}" ]
    then
        export GIT_AUTHOR_DATE="#{future.asctime}";
        export GIT_COMMITTER_DATE="#{future.asctime}";
        git commit-tree "$@";
    else
        git commit-tree "$@";
    fi' HEAD)
end

References

• http://stackoverflow.com/questions/13035324/change-all-commit-dates-in-git
• http://stackoverflow.com/questions/454734/how-can-one-change-the-timestamp-of-an-old-commit-in-git
• https://help.github.com/articles/changing-author-info/
• https://github.com/schacon/ruby-git
• http://guides.rubyonrails.org/active_support_core_extensions.html#time
• http://git-scm.com/docs/git-commit-tree