Deprecated Float#years and Float#months, moved Numeric#years and Numeric#months into Integer.

activesupport/lib/active_support/core_ext/float.rb

 require 'active_support/core_ext/float/rounding'
+require 'active_support/core_ext/float/time'
 
 class Float #:nodoc:
   include ActiveSupport::CoreExtensions::Float::Rounding
+  include ActiveSupport::CoreExtensions::Float::Time
 end

activesupport/lib/active_support/core_ext/float/time.rb

+module ActiveSupport #:nodoc:
+  module CoreExtensions #:nodoc:
+    module Float #:nodoc:
+      module Time
+        # Deprication helper methods not available as core_ext is loaded first.
+        def years
+          ::ActiveSupport::Deprecation.warn(self.class.deprecated_method_warning(:years), caller)
+          years_without_deprecation
+        end
+        def months
+          ::ActiveSupport::Deprecation.warn(self.class.deprecated_method_warning(:months), "Fractional months are not respected. Use .to_i before ", caller)
+          months_without_deprecation
+        end
+
+        def months_without_deprecation
+          ActiveSupport::Duration.new(self * 30.days, [[:months, self]])
+        end
+        alias :month :months
+      
+        def years_without_deprecation
+          ActiveSupport::Duration.new(self * 365.25.days, [[:years, self]])
+        end
+        alias :year :years
+      end
+    end
+  end
+end
\ No newline at end of file

activesupport/lib/active_support/core_ext/integer.rb

 require 'active_support/core_ext/integer/even_odd'
 require 'active_support/core_ext/integer/inflections'
+require 'active_support/core_ext/integer/time'
 
 class Integer #:nodoc:
   include ActiveSupport::CoreExtensions::Integer::EvenOdd
   include ActiveSupport::CoreExtensions::Integer::Inflections
+  include ActiveSupport::CoreExtensions::Integer::Time
 end

activesupport/lib/active_support/core_ext/integer/time.rb

+module ActiveSupport #:nodoc:
+  module CoreExtensions #:nodoc:
+    module Integer #:nodoc:
+      # Enables the use of time calculations and declarations, like 45.minutes + 2.hours + 4.years.
+      #
+      # These methods use Time#advance for precise date calculations when using from_now, ago, etc. 
+      # as well as adding or subtracting their results from a Time object. For example:
+      #
+      #   # equivalent to Time.now.advance(:months => 1)
+      #   1.month.from_now
+      #
+      #   # equivalent to Time.now.advance(:years => 2)
+      #   2.years.from_now
+      #
+      #   # equivalent to Time.now.advance(:months => 4, :years => 5)
+      #   (4.months + 5.years).from_now
+      # 
+      # While these methods provide precise calculation when used as in the examples above, care
+      # should be taken to note that this is not true if the result of `months', `years', etc is
+      # converted before use:
+      #
+      #   # equivalent to 30.days.to_i.from_now
+      #   1.month.to_i.from_now
+      #
+      #   # equivalent to 365.25.days.to_f.from_now
+      #   1.year.to_f.from_now
+      #
+      # In such cases, Ruby's core
+      # Date[http://stdlib.rubyonrails.org/libdoc/date/rdoc/index.html] and
+      # Time[http://stdlib.rubyonrails.org/libdoc/time/rdoc/index.html] should be used for precision
+      # date and time arithmetic
+      module Time        
+        def months
+          ActiveSupport::Duration.new(self * 30.days, [[:months, self]])
+        end
+        alias :month :months
+
+        def years
+          ActiveSupport::Duration.new(self * 365.25.days, [[:years, self]])
+        end
+        alias :year :years
+      end
+    end
+  end
+end

activesupport/lib/active_support/core_ext/numeric/time.rb

@@ -60,16 +60,6 @@ def fortnights
         end
         alias :fortnight :fortnights
         
-        def months
-          ActiveSupport::Duration.new(self * 30.days, [[:months, self]])
-        end
-        alias :month :months
-
-        def years
-          ActiveSupport::Duration.new(self * 365.25.days, [[:years, self]])
-        end
-        alias :year :years
-
         # Reads best without arguments:  10.minutes.ago
         def ago(time = ::Time.now)
           time - self

activesupport/test/core_ext/duration_test.rb

@@ -64,6 +64,24 @@ def test_since_and_ago_with_fractional_weeks
       assert_equal((7 * 36).hours.ago, 1.5.weeks.ago)
       assert_equal((7 * 24 * 1.7).hours.ago, 1.7.weeks.ago)
     end
+    
+    def test_deprecated_fractional_years
+      assert_deprecated{1.0.years}
+      assert_deprecated{1.5.years}
+      assert_not_deprecated{1.years}
+      assert_deprecated{1.0.year}
+      assert_deprecated{1.5.year}
+      assert_not_deprecated{1.year}
+    end
+    
+    def test_deprecated_fractional_months
+      assert_deprecated{1.5.months}
+      assert_deprecated{1.0.months}
+      assert_not_deprecated{1.months}
+      assert_deprecated{1.5.month}
+      assert_deprecated{1.0.month}
+      assert_not_deprecated{1.month}
+    end
 
     def test_since_and_ago_anchored_to_time_now_when_time_zone_default_not_set
       Time.zone_default = nil