Added freezing time method

lib/flux_capacitor.rb

@@ -26,28 +26,43 @@ def jump(seconds)
     end
 
     def now
+      return frozen_time if frozen_time
       Time.now_without_delorean - time_travel_offsets.inject(0){ |sum, val| sum + val }
     end
 
+    def freeze_time(time = Time.now, options={})      
+      mock_current_time time, options
+      @@frozen_time =  Time.now
+    end
+
     private
+    def frozen_time
+      @@frozen_time ||= false
+    end
 
     def time_travel_offsets
       @@time_travel_offsets ||= []
     end
 
     def reset
       @@time_travel_offsets = []
+      unfreeze_time
     end
 
-    def mock_current_time(time, options={})
+    def mock_current_time(time, options={})      
       time = Chronic.parse(time, options) if time.is_a?(String)
       time = Time.local(time.year, time.month, time.day) if time.is_a?(Date) && !time.is_a?(DateTime)
-
+      unfreeze_time
       time_travel_offsets.push Time.now - time
     end
 
     def restore_previous_time
       time_travel_offsets.pop
     end
+
+    def unfreeze_time
+      @@frozen_time = nil
+    end
   end
 end
+

spec/delorean_spec.rb

@@ -1,7 +1,9 @@
 require 'rubygems'
 require 'active_support/all'
+
 require File.expand_path("../lib/delorean", File.dirname(__FILE__))
 
+
 describe Delorean do
 
   before(:all) do
@@ -197,5 +199,47 @@
       Time.now.should be_within(1).of(expected)
     end
   end
+  describe "freeze_time" do
+    it "should freeze the time to now" do
+      expected = Delorean.freeze_time
+      sleep 0.01 
+      Time.now.should be_within(0.01).of(expected)
+      Time.now_without_delorean.should_not be_within(0.01).of(expected)
+    end
+
+    it "should freeze the time to given date" do
+      a_year_ago = Chronic.parse "1 year ago"
+      Delorean.freeze_time a_year_ago
+      sleep 0.01 
+      expected = a_year_ago
+      Time.now.should be_within(0.01).of(expected)
+      Time.now_without_delorean.should_not be_within(0.01).of(expected)
+    end
+
+    it "should unfreeze on new time travel" do
+      a_year_ago = Chronic.parse "1 year ago"
+      Delorean.freeze_time a_year_ago
+      Delorean.jump 12
+      expected = Time.now
+      sleep 0.01
+      Time.now.should be_within(13).of(a_year_ago)
+      Time.now.should_not be_within(0.01).of(expected)
+      Delorean.freeze_time
+      Delorean.time_travel_to a_year_ago
+      expected = Time.now
+      sleep 0.01
+      Time.now.should_not be_within(0.01).of(expected)
+    end
+
+    it "should back_to_the_present after freezen" do
+      expected = Time.now
+      a_year_ago = Chronic.parse "1 year ago"
+      Delorean.freeze_time a_year_ago
+      Delorean.back_to_the_present
+      Time.now.should be_within(1).of(expected)
+    end
+
+  end
 end
 
+