1 files changed, 69 insertions, 0 deletions
diff --git a/activemodel/lib/active_model/type/helpers/time_value.rb b/activemodel/lib/active_model/type/helpers/time_value.rb
new file mode 100644
index 0000000000..5a899d43ec
--- /dev/null
+++ b/activemodel/lib/active_model/type/helpers/time_value.rb
@@ -0,0 +1,69 @@
+module ActiveModel
+  module Type
+    module Helpers
+      module TimeValue # :nodoc:
+        def serialize(value)
+          if precision && value.respond_to?(:usec)
+            number_of_insignificant_digits = 6 - precision
+            round_power = 10 ** number_of_insignificant_digits
+            value = value.change(usec: value.usec / round_power * round_power)
+          end
+
+          if value.acts_like?(:time)
+            zone_conversion_method = is_utc? ? :getutc : :getlocal
+
+            if value.respond_to?(zone_conversion_method)
+              value = value.send(zone_conversion_method)
+            end
+          end
+
+          value
+        end
+        
+        def is_utc?
+          ::Time.zone_default =~ 'UTC'
+        end
+        
+        def default_timezone
+          ::Time.zone_default
+        end
+
+        def type_cast_for_schema(value)
+          "'#{value.to_s(:db)}'"
+        end
+
+        def user_input_in_time_zone(value)
+          value.in_time_zone
+        end
+
+        private
+
+        def new_time(year, mon, mday, hour, min, sec, microsec, offset = nil)
+          # Treat 0000-00-00 00:00:00 as nil.
+          return if year.nil? || (year == 0 && mon == 0 && mday == 0)
+          
+
+          if offset
+            time = ::Time.utc(year, mon, mday, hour, min, sec, microsec) rescue nil
+            return unless time
+
+            time -= offset
+            is_utc? ? time : time.getlocal
+          else
+            ::Time.public_send(default_timezone, year, mon, mday, hour, min, sec, microsec) rescue nil
+          end
+        end
+        
+        ISO_DATETIME = /\A(\d{4})-(\d\d)-(\d\d) (\d\d):(\d\d):(\d\d)(\.\d+)?\z/
+
+        # Doesn't handle time zones.
+        def fast_string_to_time(string)
+          if string =~ ISO_DATETIME
+            microsec = ($7.to_r * 1_000_000).to_i
+            new_time $1.to_i, $2.to_i, $3.to_i, $4.to_i, $5.to_i, $6.to_i, microsec
+          end
+        end
+      end
+    end
+  end
+end