timecop¶ ↑

• github.com/jtrupiano/timecop

WHAT THIS FORK DOES¶ ↑

This is a fork of the Timecop gem. This fork make use of file caches to store the offset and values of the mock time objects. This allows different processes to read and write to the mock objects. The motivation is to enable Culerity to use timecop.

Cache Files¶ ↑

Two timecop cache files are created in your home directory. They are .timecop-cache.time.cache and .timecop-cache.offset.cache

Cucumber Usage¶ ↑

#Cucumber feature
Scenario: Invitees receives reminder email when event approaches
  Given event "Weather Conference" is published
  And the event starts at "2006-March-3 00:00"
  And the event has set reminder emails to be sent "2" days before the event starts
  And the event has the following invitees:
  """
  [email protected], [email protected], [email protected]
  """
  And the time now is "1-3-2006 00:00"
  When the scheduler sends the reminder emails
  Then "[email protected], [email protected], [email protected]" should receive a "Reminder to attend Weather Conference" email 

#In your step definitions 
Given /^the time now is "(\d+)-(\d+)-(\d+) (\d\d):(\d\d)"$/ do |day, month, year, hr, min|
  Timecop.freeze(Time.local(year, month, day, hr, min))
end

#In your env.rb
Before do
  clear_time_cache
end

def clear_time_cache
  time_cache = File.expand_path('~/.timecop-cache.time.cache')
  offset_cache = File.expand_path('~/.timecop-cache.offset.cache')
  File.delete(time_cache) if File.exist?(time_cache)
  File.delete(offset_cache) if File.exist?(offset_cache)
end

DESCRIPTION¶ ↑

A gem providing “time travel” and “time freezing” capabilities, making it dead simple to test time-dependent code. It provides a unified method to mock Time.now, Date.today, and DateTime.now in a single call.

FEATURES¶ ↑

• Freeze time to a specific point.

• Travel back to a specific point in time, but allow time to continue moving forward from there.

• Timecop api allows arguments to be passed into #freeze and #travel as one of the following:

  • Time instance

  • DateTime instance

  • Date instance

  • individual arguments (year, month, day, hour, minute, second)

  • a single integer argument that is interpreted as an offset in seconds from Time.now

• Nested calls to Timecop#travel and Timecop#freeze are supported – each block will maintain its interpretation of now.

USAGE¶ ↑

Run a time-sensitive test

joe = User.find(1)
joe.purchase_home()
assert !joe.mortgage_due?
# move ahead a month and assert that the mortgage is due
Timecop.freeze(Date.today + 30) do
  assert joe.mortgage_due?
end

Set the time for the test environment of a rails app – this is particularly helpful if your whole application is time-sensitive. It allows you to build your test data at a single point in time, and to move in/out of that time as appropriate (within your tests)

in config/environments/test.rb

config.after_initialize do
  # Set Time.now to September 1, 2008 10:05:00 AM (at this instant), but allow it to move forward
  t = Time.local(2008, 9, 1, 10, 5, 0)
  Timecop.travel(t)
end

The difference between Timecop.freeze and Timecop.travel¶ ↑

#freeze is used to statically mock the concept of now. As your program executes, Time.now will not change unless you make subsequent calls into the Timecop API. #travel, on the other hand, computes an offset between what we currently think Time.now is (recall that we support nested traveling) and the time passed in. It uses this offset to simulate the passage of time. To demonstrate, consider the following code snippets:

new_time = Time.local(2008, 9, 1, 12, 0, 0)
Timecop.freeze(new_time)
sleep(10)
new_time == Time.now # ==> true

Timecop.return # "turn off" Timecop
Timecop.travel(new_time)
sleep(10)
new_time == Time.now # ==> false

DEPENDENCIES¶ ↑

• None

INSTALL¶ ↑

• sudo gem install liangzan-timecop

REFERENCES¶ ↑

• “0.2.0 release”:blog.smartlogicsolutions.com/2008/12/24/timecop-2-released-freeze-and-rebase-time-ruby/

• “0.1.0 release”:blog.smartlogicsolutions.com/2008/11/19/timecop-freeze-time-in-ruby-for-better-testing/