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rootulp's solution

to Gigasecond in the Ruby Track

Published at Jul 13 2018 · 0 comments
Test suite


This solution was written on an old version of Exercism. The tests below might not correspond to the solution code, and the exercise may have changed since this code was written.

Calculate the moment when someone has lived for 10^9 seconds.

A gigasecond is 10^9 (1,000,000,000) seconds.

For installation and learning resources, refer to the exercism help page.

For running the tests provided, you will need the Minitest gem. Open a terminal window and run the following command to install minitest:

gem install minitest

If you would like color output, you can require 'minitest/pride' in the test file, or note the alternative instruction, below, for running the test file.

Run the tests from the exercise directory using the following command:

ruby gigasecond_test.rb

To include color from the command line:

ruby -r minitest/pride gigasecond_test.rb


Chapter 9 in Chris Pine's online Learn to Program tutorial. http://pine.fm/LearnToProgram/?Chapter=09

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.


require 'minitest/autorun'
require_relative 'gigasecond'

# Common test data version: 1.0.0 61e7d70
class GigasecondTest < Minitest::Test
  def test_date_only_specification_of_time
    # skip
    assert_equal Time.utc(2043, 1, 1, 1, 46, 40), Gigasecond.from(Time.utc(2011, 4, 25, 0, 0, 0))

  def test_second_test_for_date_only_specification_of_time
    assert_equal Time.utc(2009, 2, 19, 1, 46, 40), Gigasecond.from(Time.utc(1977, 6, 13, 0, 0, 0))

  def test_third_test_for_date_only_specification_of_time
    assert_equal Time.utc(1991, 3, 27, 1, 46, 40), Gigasecond.from(Time.utc(1959, 7, 19, 0, 0, 0))

  def test_full_time_specified
    assert_equal Time.utc(2046, 10, 2, 23, 46, 40), Gigasecond.from(Time.utc(2015, 1, 24, 22, 0, 0))

  def test_full_time_with_day_roll_over
    assert_equal Time.utc(2046, 10, 3, 1, 46, 39), Gigasecond.from(Time.utc(2015, 1, 24, 23, 59, 59))

  # Problems in exercism evolve over time, as we find better ways to ask
  # questions.
  # The version number refers to the version of the problem you solved,
  # not your solution.
  # Define a constant named VERSION inside of the top level BookKeeping
  # module, which may be placed near the end of your file.
  # In your file, it will look like this:
  # module BookKeeping
  #   VERSION = 1 # Where the version number matches the one in the test.
  # end
  # If you are curious, read more about constants on RubyDoc:
  # http://ruby-doc.org/docs/ruby-doc-bundle/UsersGuide/rg/constants.html

  def test_bookkeeping
    assert_equal 6, BookKeeping::VERSION
require 'date'
require 'time'

# Gigasecond
class Gigasecond
  def self.from(date)
    (date.to_time + 10**9).to_date

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