require 'active_support/core_ext/string/strip' # for strip_heredoc require 'concurrent/map' module ActiveSupport module Testing class SimpleStubs # :nodoc: Stub = Struct.new(:object, :method_name, :original_method) def initialize @stubs = Concurrent::Map.new { |h, k| h[k] = {} } end def stub_object(object, method_name, return_value) if stub = stubbing(object, method_name) unstub_object(stub) end new_name = "__simple_stub__#{method_name}" @stubs[object.object_id][method_name] = Stub.new(object, method_name, new_name) object.singleton_class.send :alias_method, new_name, method_name object.define_singleton_method(method_name) { return_value } end def unstub_all! @stubs.each_value do |object_stubs| object_stubs.each_value do |stub| unstub_object(stub) end end @stubs.clear end def stubbing(object, method_name) @stubs[object.object_id][method_name] end private def unstub_object(stub) singleton_class = stub.object.singleton_class singleton_class.send :undef_method, stub.method_name singleton_class.send :alias_method, stub.method_name, stub.original_method singleton_class.send :undef_method, stub.original_method end end # Contains helpers that help you test passage of time. module TimeHelpers # Changes current time to the time in the future or in the past by a given time difference by # stubbing +Time.now+, +Date.today+, and +DateTime.now+. # # Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00 # travel 1.day # Time.current # => Sun, 10 Nov 2013 15:34:49 EST -05:00 # Date.current # => Sun, 10 Nov 2013 # DateTime.current # => Sun, 10 Nov 2013 15:34:49 -0500 # # This method also accepts a block, which will return the current time back to its original # state at the end of the block: # # Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00 # travel 1.day do # User.create.created_at # => Sun, 10 Nov 2013 15:34:49 EST -05:00 # end # Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00 def travel(duration, &block) travel_to Time.now + duration, &block end # Changes current time to the given time by stubbing +Time.now+, # +Date.today+, and +DateTime.now+ to return the time or date passed into this method. # # Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00 # travel_to Time.zone.local(2004, 11, 24, 01, 04, 44) # Time.current # => Wed, 24 Nov 2004 01:04:44 EST -05:00 # Date.current # => Wed, 24 Nov 2004 # DateTime.current # => Wed, 24 Nov 2004 01:04:44 -0500 # # Dates are taken as their timestamp at the beginning of the day in the # application time zone. Time.current returns said timestamp, # and Time.now its equivalent in the system time zone. Similarly, # Date.current returns a date equal to the argument, and # Date.today the date according to Time.now, which may # be different. (Note that you rarely want to deal with Time.now, # or Date.today, in order to honor the application time zone # please always use Time.current and Date.current.) # # Note that the usec for the time passed will be set to 0 to prevent rounding # errors with external services, like MySQL (which will round instead of floor, # leading to off-by-one-second errors). # # This method also accepts a block, which will return the current time back to its original # state at the end of the block: # # Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00 # travel_to Time.zone.local(2004, 11, 24, 01, 04, 44) do # Time.current # => Wed, 24 Nov 2004 01:04:44 EST -05:00 # end # Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00 def travel_to(date_or_time) if block_given? && simple_stubs.stubbing(Time, :now) travel_to_nested_block_call = <<-MSG.strip_heredoc Calling `travel_to` with a block, when we have previously already made a call to `travel_to`, can lead to confusing time stubbing. Instead of: travel_to 2.days.from_now do # 2 days from today travel_to 3.days.from_now do # 5 days from today end end preferred way to achieve above is: travel 2.days do # 2 days from today end travel 5.days do # 5 days from today end MSG raise travel_to_nested_block_call end if date_or_time.is_a?(Date) && !date_or_time.is_a?(DateTime) now = date_or_time.midnight.to_time else now = date_or_time.to_time.change(usec: 0) end simple_stubs.stub_object(Time, :now, now) simple_stubs.stub_object(Date, :today, now.to_date) simple_stubs.stub_object(DateTime, :now, now.to_datetime) if block_given? begin yield ensure travel_back end end end # Returns the current time back to its original state, by removing the stubs added by # `travel` and `travel_to`. # # Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00 # travel_to Time.zone.local(2004, 11, 24, 01, 04, 44) # Time.current # => Wed, 24 Nov 2004 01:04:44 EST -05:00 # travel_back # Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00 def travel_back simple_stubs.unstub_all! end private def simple_stubs @simple_stubs ||= SimpleStubs.new end end end end