add casting support in the AR driver specifically for handling default column values - this is a temporary (but working) fix as I'm looking into how I can do this in C

lib/active_record/connection_adapters/mysql2_adapter.rb

@@ -13,6 +13,7 @@ module ActiveRecord
 
   module ConnectionAdapters
     class Mysql2Column < Column
+      BOOL = "tinyint(1)".freeze
       def extract_default(default)
         if sql_type =~ /blob/i || type == :text
           if default.blank?
@@ -49,10 +50,20 @@ module ActiveRecord
       end
 
       def type_cast(value)
-        if type == :boolean
+        return nil if value.nil?
-          self.class.value_to_boolean(value)
+        case type
-        else
+          when :string    then value
-          value
+          when :text      then value
+          when :integer   then value.to_i rescue value ? 1 : 0 unless value.is_a?(Fixnum)
+          when :float     then value.to_f unless value.is_a?(Float)
+          when :decimal   then self.class.value_to_decimal(value) unless value.class == BigDecimal
+          when :datetime  then self.class.string_to_time(value) unless value.class == Time
+          when :timestamp then self.class.string_to_time(value) unless value.class == Time
+          when :time      then self.class.string_to_dummy_time(value) unless value.class == Time
+          when :date      then self.class.string_to_date(value) unless value.class == Date
+          when :binary    then value
+          when :boolean   then self.class.value_to_boolean(value)
+          else value
         end
       end
 
@@ -62,8 +73,9 @@ module ActiveRecord
 
       private
         def simplified_type(field_type)
-          return :boolean if Mysql2Adapter.emulate_booleans && field_type.downcase.index("tinyint(1)")
+          return :boolean if Mysql2Adapter.emulate_booleans && field_type.downcase.index(BOOL)
           return :string  if field_type =~ /enum/i
+          return :integer if field_type =~ /year/i
           super
         end
 

spec/active_record/active_record_spec.rb

@@ -3,6 +3,10 @@ require File.expand_path(File.dirname(__FILE__) + '/../spec_helper.rb')
 require 'active_record'
 require 'active_record/connection_adapters/mysql2_adapter'
 
+class Mysql2Test2 < ActiveRecord::Base
+  set_table_name "mysql2_test2"
+end
+
 describe ActiveRecord::ConnectionAdapters::Mysql2Adapter do
   it "should be able to connect" do
     lambda {
@@ -20,4 +24,85 @@ describe ActiveRecord::ConnectionAdapters::Mysql2Adapter do
       @connection.execute("SELECT NOW() as n").first['n'].class.should eql(Time)
     end
   end
+  
+  context "columns" do
+    before(:all) do
+      ActiveRecord::Base.establish_connection(:adapter => 'mysql2', :database => 'test')
+      Mysql2Test2.connection.execute %[
+        CREATE TABLE IF NOT EXISTS mysql2_test2 (
+          `id` mediumint(9) NOT NULL AUTO_INCREMENT,
+          `null_test` varchar(10) DEFAULT NULL,
+          `bit_test` bit(64) NOT NULL DEFAULT b'1',
+          `tiny_int_test` tinyint(4) NOT NULL DEFAULT '1',
+          `small_int_test` smallint(6) NOT NULL DEFAULT '1',
+          `medium_int_test` mediumint(9) NOT NULL DEFAULT '1',
+          `int_test` int(11) NOT NULL DEFAULT '1',
+          `big_int_test` bigint(20) NOT NULL DEFAULT '1',
+          `float_test` float(10,3) NOT NULL DEFAULT '1.000',
+          `double_test` double(10,3) NOT NULL DEFAULT '1.000',
+          `decimal_test` decimal(10,3) NOT NULL DEFAULT '1.000',
+          `date_test` date NOT NULL DEFAULT '2010-01-01',
+          `date_time_test` datetime NOT NULL DEFAULT '2010-01-01 00:00:00',
+          `timestamp_test` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+          `time_test` time NOT NULL DEFAULT '00:00:00',
+          `year_test` year(4) NOT NULL DEFAULT '2010',
+          `char_test` char(10) NOT NULL DEFAULT 'abcdefghij',
+          `varchar_test` varchar(10) NOT NULL DEFAULT 'abcdefghij',
+          `binary_test` binary(10) NOT NULL DEFAULT 'abcdefghij',
+          `varbinary_test` varbinary(10) NOT NULL DEFAULT 'abcdefghij',
+          `tiny_blob_test` tinyblob NOT NULL,
+          `tiny_text_test` tinytext,
+          `blob_test` blob,
+          `text_test` text,
+          `medium_blob_test` mediumblob,
+          `medium_text_test` mediumtext,
+          `long_blob_test` longblob,
+          `long_text_test` longtext,
+          `enum_test` enum('val1','val2') NOT NULL DEFAULT 'val1',
+          `set_test` set('val1','val2') NOT NULL DEFAULT 'val1,val2',
+          PRIMARY KEY (`id`)
+        )
+      ]
+      Mysql2Test2.connection.execute "INSERT INTO mysql2_test2 (null_test) VALUES (NULL)"
+      @test_result = Mysql2Test2.connection.execute("SELECT * FROM mysql2_test2 ORDER BY id DESC LIMIT 1").first
+    end
+
+    after(:all) do
+      Mysql2Test2.connection.execute("DELETE FROM mysql2_test WHERE id=#{@test_result['id']}")
+    end
+
+    it "default value should be cast to the expected type of the field" do
+      test = Mysql2Test2.new
+      test.null_test.should be_nil
+      test.bit_test.should eql("b'1'")
+      test.tiny_int_test.should eql(1)
+      test.small_int_test.should eql(1)
+      test.medium_int_test.should eql(1)
+      test.int_test.should eql(1)
+      test.big_int_test.should eql(1)
+      test.float_test.should eql('1.0000'.to_f)
+      test.double_test.should eql('1.0000'.to_f)
+      test.decimal_test.should eql(BigDecimal.new('1.0000'))
+      test.date_test.should eql(Date.parse('2010-01-01'))
+      test.date_time_test.should eql(Time.parse('2010-01-01 00:00:00'))
+      test.timestamp_test.should be_nil
+      test.time_test.class.should eql(Time)
+      test.year_test.should eql(2010)
+      test.char_test.should eql('abcdefghij')
+      test.varchar_test.should eql('abcdefghij')
+      test.binary_test.should eql('abcdefghij')
+      test.varbinary_test.should eql('abcdefghij')
+      test.tiny_blob_test.should eql("")
+      test.tiny_text_test.should be_nil
+      test.blob_test.should be_nil
+      test.text_test.should be_nil
+      test.medium_blob_test.should be_nil
+      test.medium_text_test.should be_nil
+      test.long_blob_test.should be_nil
+      test.long_text_test.should be_nil
+      test.long_blob_test.should be_nil
+      test.enum_test.should eql('val1')
+      test.set_test.should eql('val1,val2')
+    end
+  end
 end