time helpers honor the application time zone when passed a date

Rails applications are expected to be always aware of the application
time zone.

To be consistent with that contract, we have to assume that a bare
date passed to time helpers is a date in the application time zone,
not in the system time zone. The system time zone is irrelevant, we
should totally ignore it.

For example,

    travel_to user.birth_date + 40.years

should make that user be 40th years old regardless of the system
time zone. Without this patch that may not be true.

1 files changed, 14 insertions, 0 deletions

diff --git a/activesupport/test/time_zone_test.rb b/activesupport/test/time_zone_test.rb
index cd79efbe8c..48bcfa6929 100644
--- a/activesupport/test/time_zone_test.rb
+++ b/activesupport/test/time_zone_test.rb
@@ -124,6 +124,20 @@ class TimeZoneTest < ActiveSupport::TestCase
     travel_back
   end
 
+  def test_travel_to_a_date
+    with_env_tz do
+      Time.use_zone('Hawaii') do
+        date = Date.new(2014, 2, 18)
+        time = date.midnight
+
+        travel_to date
+
+        assert_equal date, Date.current
+        assert_equal time, Time.current
+      end
+    end
+  end
+
   def test_local
     time = ActiveSupport::TimeZone["Hawaii"].local(2007, 2, 5, 15, 30, 45)
     assert_equal Time.utc(2007, 2, 5, 15, 30, 45), time.time