Dates and times interpret empty strings as nil rather than 2000-01-01. Closes #4830.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4327 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* Dates and times interpret empty strings as nil rather than 2000-01-01. #4830 [kajism@yahoo.com]
+
 * Allow :uniq => true with has_many :through associations. [Jeremy Kemper]
 
 * Ensure that StringIO is always available for the Schema dumper. [Marcel Molina Jr.]

activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb

@@ -115,6 +115,7 @@ module ActiveRecord
 
       def self.string_to_dummy_time(string)
         return string unless string.is_a?(String)
+        return nil if string.empty?
         time_array = ParseDate.parsedate(string)
         # pad the resulting array with dummy date information
         time_array[0] = 2000; time_array[1] = 1; time_array[2] = 1;

activerecord/test/empty_date_time_test.rb

@@ -0,0 +1,25 @@
+require 'abstract_unit'
+require 'fixtures/topic'
+require 'fixtures/task'
+
+class EmptyDateTimeTest < Test::Unit::TestCase
+  def test_assign_empty_date_time
+    task = Task.new
+    task.starting = ''
+    task.ending = nil
+    assert_nil task.starting
+    assert_nil task.ending
+  end
+
+  def test_assign_empty_date
+    topic = Topic.new
+    topic.last_read = ''
+    assert_nil topic.last_read
+  end
+
+  def test_assign_empty_time
+    topic = Topic.new
+    topic.bonus_time = ''
+    assert_nil topic.bonus_time
+  end
+end