Improve documentation [ci skip]

activesupport/lib/active_support/testing/time_helpers.rb

@@ -41,7 +41,7 @@ def unstub_object(stub)
 
     # Containing helpers that helps you test passage of time.
     module TimeHelpers
-      # Change current time to the time in the future or in the past by a given time difference by
+      # Changes current time to the time in the future or in the past by a given time difference by
       # stubbing +Time.now+ and +Date.today+.
       #
       #   Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00
@@ -61,7 +61,7 @@ def travel(duration, &block)
         travel_to Time.now + duration, &block
       end
 
-      # Change current time to the given time by stubbing +Time.now+ and +Date.today+ to return the
+      # Changes current time to the given time by stubbing +Time.now+ and +Date.today+ to return the
       # time or date passed into this method.
       #
       #   Time.current # => Sat, 09 Nov 2013 15:34:49 EST -05:00
@@ -87,7 +87,8 @@ def travel_to(date_or_time, &block)
         end
       end
 
-      # Return the current time back to its original state.
+      # 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.new(2004, 11, 24, 01, 04, 44)

guides/source/4_1_release_notes.md

@@ -607,8 +607,9 @@ for detailed changes.
   `Time.now` and
   `Date.today`. ([Pull Request](https://github.com/rails/rails/pull/12824))
 
-* Added `ActiveSupport::Testing::TimeHelpers#travel_back`. This method return
-  the current time to the original state. ([Pull Request](https://github.com/rails/rails/pull/13884))
+* Added `ActiveSupport::Testing::TimeHelpers#travel_back`. This method returns
+  the current time to the original state, by removing the stubs added by `travel`
+  and `travel_to`. ([Pull Request](https://github.com/rails/rails/pull/13884))
 
 * Added `Numeric#in_milliseconds`, like `1.hour.in_milliseconds`, so we can feed
   them to JavaScript functions like