Rake Timer

rake_timer.rb

require 'rake'

Rake::Task.class_eval do

  alias :execute_without_tracing :execute

  def execute(*args)
    @executed_at = Time.now
    execute_without_tracing(*args)
  end

  alias :invoke_with_call_chain_without_tracing :invoke_with_call_chain

  def invoke_with_call_chain(*args)
    @invoked_at = Time.now
    result = invoke_with_call_chain_without_tracing(*args)
    show_timings
    result
  ensure
    @invoked_at = @executed_at = nil
  end

  def show_timings
    return if application.options.dryrun
    return unless @executed_at
    finished_at = Time.now
    execution_time = finished_at - @executed_at
    invocation_time = finished_at - @invoked_at
    printf("=> Completed task %-40s (in %.2fs total, %.2fs exclusive)\n", name, invocation_time, execution_time)
  end

end

Rakefile

require 'rake_timer'