added strict_time_type_cast method to handle casting

refactored to be simler and rely on read_atribute method conversion
rather than use new reader method definer got time (Rails 2.1)

lib/validates_timeliness/attribute_methods.rb

@@ -5,9 +5,9 @@
 #
 # For Rails >= 2.1  
 #   This module overrides these AR methods to allow a time value passed to a column 
-#   write method to be stored as is and converts it to a time and caches on read.
+#   write method to be stored as is and only convert to a time on read.
-#   This differs from the normal AR behvaviour where the value is converted and
+#   This differs from the current AR behvaviour where the value is converted
-#   cached on write.
+#   on write.
 #
 #   This allows the before_type_cast method for the column to return the actual 
 #   value passed to it, treating time columns like all other column types.
@@ -25,25 +25,7 @@ module ValidatesTimeliness
     module ClassMethods
       # Rails > 2.0.2
       module New
-        def define_read_method_for_time_zone_conversion(attr_name)
+        # Store time value as is including as a string. Only convert on read
-          method_body = <<-EOV          
-            def #{attr_name}(reload = false)
-              cached = @attributes_cache['#{attr_name}']
-              return cached if cached && !reload
-              time = read_attribute_before_type_cast('#{attr_name}')
-              if time.acts_like?(:time)
-                time = time.in_time_zone
-              elsif time
-                # check invalid date
-                time.to_date rescue time = nil
-                time = time.is_a?(String) ? Time.zone.parse(time) : time.to_time rescue time if time
-              end
-              @attributes_cache['#{attr_name}'] = time
-            end
-          EOV
-          evaluate_attribute_method attr_name, method_body
-        end
-        
         def define_write_method_for_time_zone_conversion(attr_name)
           method_body = <<-EOV
             def #{attr_name}=(time)
@@ -59,18 +41,17 @@ module ValidatesTimeliness
     
       # Rails <= 2.0.2
       module Old
+        # Copied from AR and inserted Time class check to time attribute
         def define_attribute_methods
           return if generated_methods?
           columns_hash.each do |name, column|
             unless instance_method_already_implemented?(name)
               if self.serialized_attributes[name]
                 define_read_method_for_serialized_attribute(name)
+              elsif column.klass == Time        
+                define_read_method_for_time_attribute(name.to_sym)
               else
-                if column.klass == Time                  
+                define_read_method(name.to_sym, name, column)
-                  define_read_method_for_time_attribute(name.to_sym)
-                else 
-                  define_read_method(name.to_sym, name, column)
-                end
               end
             end
 
@@ -84,19 +65,14 @@ module ValidatesTimeliness
           end
         end
 
+        # defines time attribute reader and does conversion strict
         def define_read_method_for_time_attribute(attr_name)
           method_body = <<-EOV          
           def #{attr_name}(reload = false)
             cached = @attributes_cache['#{attr_name}']
             return cached if cached && !reload
             time = read_attribute_before_type_cast('#{attr_name}')
-            unless time.acts_like?(:time)
+            time = strict_time_type_cast(time)
-              klass = ActiveRecord::ConnectionAdapters::Column
-              # check for invalid date
-              time = nil unless klass.string_to_date(time)
-              # convert to time if still valid
-              time = klass.string_to_time(time) if time
-            end
             @attributes_cache['#{attr_name}'] = time
           end
           EOV

lib/validates_timeliness/base.rb

@@ -6,6 +6,7 @@ module ValidatesTimeliness
       time_array[0..2].join('-') + ' ' + time_array[3..5].join(':')
     end
   
+    # Overrides AR method to store multiparameter time and dates 
     def execute_callstack_for_multiparameter_attributes(callstack)
       errors = []
       callstack.each do |name, values|
@@ -30,5 +31,36 @@ module ValidatesTimeliness
       end
     end
     
+    def strict_time_type_cast(time)
+      if time.acts_like?(:time)
+        time.respond_to?(:in_time_zone) ? time.time.in_time_zone : time
+      else
+        klass = ActiveRecord::ConnectionAdapters::Column
+        # check for invalid date
+        time = nil unless klass.string_to_date(time)
+        # convert to time if still valid
+        time = klass.string_to_time(time) if time
+      end
+    end
+    
+    def read_attribute(attr_name)
+      attr_name = attr_name.to_s
+      if !(value = @attributes[attr_name]).nil?
+        if column = column_for_attribute(attr_name)
+          if unserializable_attribute?(attr_name, column)
+            unserialize_attribute(attr_name)
+          elsif column.klass == Time
+            strict_time_type_cast(value)
+          else
+            column.type_cast(value)
+          end
+        else
+          value
+        end
+      else
+        nil
+      end
+    end
+    
   end
 end

spec/attribute_methods_spec.rb

@@ -33,6 +33,9 @@ describe ValidatesTimeliness::AttributeMethods do
       end
     end
     
+    # This fails running as plugin under vendor using Rails 2.1RC
+    # due to write_attribute_with_dirty ignoring the write method for time zone
+    # method. But invalid dates do return nil when running app.
     it "should return nil when time is invalid" do
       @person.birth_date_and_time = "2000-02-30 01:02:03"
       @person.birth_date_and_time.should be_nil

spec/base_spec.rb

@@ -34,4 +34,38 @@ describe ValidatesTimeliness::Base do
       execute_callstack_for_multiparameter_attributes(callstack)
     end
   end
+  
+  describe "strict_time_type_cast" do
+    it "should return time object for valid time string" do
+      strict_time_type_cast("2000-01-01 12:13:14").should be_kind_of(Time)
+    end
+    
+    it "should return nil for time string with invalid date part" do
+      strict_time_type_cast("2000-02-30 12:13:14").should be_nil
+    end
+    
+    it "should return nil for time string with invalid time part" do
+      strict_time_type_cast("2000-02-01 25:13:14").should be_nil      
+    end
+  end
+  
+  describe "read_attribute" do
+    it "should return time object from time string" do
+      @attributes = {}
+      self.stub!(:column_for_attribute).and_return( mock('Column', :klass => Time) )
+      self.stub!(:unserializable_attribute?).and_return(false)
+      
+      @attributes['birth_date_and_time'] = "1980-01-01 00:00:00"
+      read_attribute(:birth_date_and_time).should be_kind_of(Time)
+    end
+
+    it "should return nil from invalid time string" do
+      @attributes = {}
+      self.stub!(:column_for_attribute).and_return( mock('Column', :klass => Time) )
+      self.stub!(:unserializable_attribute?).and_return(false)
+      
+      @attributes['birth_date_and_time'] = "1980-02-30 00:00:00"
+      read_attribute(:birth_date_and_time).should be_nil
+    end
+  end
 end