Added Base.validate_presence as an alternative to implementing validate and doing errors.add_on_empty yourself. Added _on_create and _on_update versions for all the new validations

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@107 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 81 insertions, 24 deletions

diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index 3a8c81453a..a914b0c276 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -12,6 +12,8 @@
       errors.on(:name)  # => "must be shorter"
       errors.on("name") # => "must be shorter"
 
+* Added Base.validate_presence as an alternative to implementing validate and doing errors.add_on_empty yourself.
+
 * Added Base.validate_confirmation that encapsulates the pattern of wanting to validate a password or email address field with a confirmation. Example:
  
      Model:
@@ -24,10 +26,9 @@
        <%= password_field "person", "password_confirmation" %>
   
    The person has to already have a password attribute (a column in the people table), but the password_confirmation is virtual.
-   It exists only as an in-memory variable for validating the password.
-  
-   NOTE: This validation is only happening on create. When you want to update the record, you'll have to decide and pursue your
-   own course of action.
+   It exists only as an in-memory variable for validating the password. This check is performed both on create and update.
+   See validate_confirmation_on_create and validate_confirmation_on_update if you want to restrict the validation to just one of the two
+   situations.
 
 
 * Added Base.validate_confirmation that encapsulates the pattern of wanting to validate the acceptance of a terms of service check box (or similar agreement). Example:
@@ -40,7 +41,9 @@
     View:
       <%= check_box "person", "terms_of_service" %>
   
-  The terms_of_service attribute is entirely virtual. It's only used for validation at the time of creation. No database column is needed.
+  The terms_of_service attribute is entirely virtual. No database column is needed. This check is performed both on create and update.
+  See validate_acceptance_on_create and validate_acceptance_on_update if you want to restrict the validation to just one of the two
+  situations.
 
   NOTE: The agreement is considered valid if it's set to the string "1". This makes it easy to relate it to an HTML checkbox.
 
diff --git a/activerecord/lib/active_record/validations.rb b/activerecord/lib/active_record/validations.rb
index 1c2680e639..17810318b7 100755
--- a/activerecord/lib/active_record/validations.rb
+++ b/activerecord/lib/active_record/validations.rb
@@ -69,21 +69,30 @@ module ActiveRecord
       #     <%= password_field "person", "password_confirmation" %>
       #
       # The person has to already have a password attribute (a column in the people table), but the password_confirmation is virtual.
-      # It exists only as an in-memory variable for validating the password.
-      #
-      # NOTE: This validation is only happening on create. When you want to update the record, you'll have to decide and pursue your
-      # own course of action.
+      # It exists only as an in-memory variable for validating the password. This check is performed both on create and update.
+      # See validate_confirmation_on_create and validate_confirmation_on_update if you want to restrict the validation to just one of the two
+      # situations.
       def validate_confirmation(*attr_names)
         error_message = attr_names.last.is_a?(String) ? attr_names.pop : "doesn't match confirmation"
 
+        validation_method = block_given? ? yield : "validate"
+
         for attr_name in attr_names
           attr_accessor "#{attr_name}_confirmation"
-          class_eval <<-EOM
-            validate_on_create %{errors.add('#{attr_name}', "#{error_message}") unless #{attr_name} == #{attr_name}_confirmation}
-EOM
+          class_eval(%(#{validation_method} %{errors.add('#{attr_name}', "#{error_message}") unless #{attr_name} == #{attr_name}_confirmation}))
         end
       end
-      
+
+      # Works like validate_confirmation, but only performs the validation on creation (for new records).
+      def validate_confirmation_on_create(*attr_names)
+        validate_confirmation(*attr_names) { "validate_on_create" }
+      end
+
+      # Works like validate_confirmation, but only performs the validation on creation (for new records).
+      def validate_confirmation_on_update(*attr_names)
+        validate_confirmation(*attr_names) { "validate_on_update" }
+      end
+
       # Encapsulates the pattern of wanting to validate the acceptance of a terms of service check box (or similar agreement). Example:
       #
       #   Model:
@@ -95,19 +104,51 @@ EOM
       #   View:
       #     <%= check_box "person", "terms_of_service" %>
       #
-      # The terms_of_service attribute is entirely virtual. It's only used for validation at the time of creation. No database column is needed.
+      # The terms_of_service attribute is entirely virtual. No database column is needed. This check is performed both on create and update.
+      # See validate_acceptance_on_create and validate_acceptance_on_update if you want to restrict the validation to just one of the two
+      # situations.
       #
       # NOTE: The agreement is considered valid if it's set to the string "1". This makes it easy to relate it to an HTML checkbox.
       def validate_acceptance(*attr_names)
         error_message = attr_names.last.is_a?(String) ? attr_names.pop : "must be accepted"
         
+        validation_method = block_given? ? yield : "validate"
+        
         for attr_name in attr_names
           attr_accessor(attr_name)
-          class_eval <<-EOM
-            validate_on_create %{errors.add('#{attr_name}', '#{error_message}') unless #{attr_name} == "1"}
-EOM
+          class_eval(%(#{validation_method} %{errors.add('#{attr_name}', '#{error_message}') unless #{attr_name} == "1"}))
         end
       end
+      
+      # Works like validate_acceptance, but only performs the validation on creation (for new records).
+      def validate_acceptance_on_create(*attr_names)
+        validate_acceptance(*attr_names) { "validate_on_create" }
+      end
+
+      # Works like validate_acceptance, but only performs the validation on update (for existing records).
+      def validate_acceptance_on_update(*attr_names)
+        validate_acceptance(*attr_names) { "validate_on_update" }
+      end
+
+      def validate_presence(*attr_names)
+        error_message = attr_names.last.is_a?(String) ? attr_names.pop : "can't be empty"
+
+        validation_method = block_given? ? yield : "validate"
+
+        for attr_name in attr_names
+          class_eval(%(#{validation_method} %{errors.add_on_empty('#{attr_name}', "#{error_message}")}))
+        end
+      end
+
+      # Works like validate_presence, but only performs the validation on creation (for new records).
+      def validate_presence_on_create(*attr_names)
+        validate_presence(*attr_names) { "validate_on_create" }
+      end
+
+      # Works like validate_presence, but only performs the validation on update (for existing records).
+      def validate_presence_on_update(*attr_names)
+        validate_presence(*attr_names) { "validate_on_update" }
+      end
     end
 
     # The validation process on save can be skipped by passing false. The regular Base#save method is
diff --git a/activerecord/test/validations_test.rb b/activerecord/test/validations_test.rb
index 8e25453fae..2d6c795d92 100755
--- a/activerecord/test/validations_test.rb
+++ b/activerecord/test/validations_test.rb
@@ -7,6 +7,11 @@ require 'fixtures/developer'
 class ValidationsTest < Test::Unit::TestCase
   fixtures :topics, :developers
 
+  def teardown
+    Topic.write_inheritable_attribute("validate", [])
+    Topic.write_inheritable_attribute("validate_on_create", [])
+  end
+
   def test_single_field_validation
     r = Reply.new
     r.title = "There's no content!"
@@ -129,12 +134,10 @@ class ValidationsTest < Test::Unit::TestCase
 
     t.title_confirmation = "We should be confirmed"
     assert t.save
-
-    Topic.write_inheritable_attribute("validate_on_create", [])
   end
 
   def test_terms_of_service_agreement
-    Topic.validate_acceptance(:terms_of_service)
+    Topic.validate_acceptance_on_create(:terms_of_service)
 
     t = Topic.create("title" => "We should be confirmed")
     assert !t.save
@@ -142,13 +145,11 @@ class ValidationsTest < Test::Unit::TestCase
 
     t.terms_of_service = "1"
     assert t.save
-
-    Topic.write_inheritable_attribute("validate_on_create", [])
   end
 
 
   def test_eula
-    Topic.validate_acceptance(:eula, "must be abided")
+    Topic.validate_acceptance_on_create(:eula, "must be abided")
 
     t = Topic.create("title" => "We should be confirmed")
     assert !t.save
@@ -156,7 +157,19 @@ class ValidationsTest < Test::Unit::TestCase
 
     t.eula = "1"
     assert t.save
+  end
+  
+  def test_validate_presences
+    Topic.validate_presence(:title, :content)
 
-    Topic.write_inheritable_attribute("validate_on_create", [])
+    t = Topic.create
+    assert !t.save
+    assert_equal "can't be empty", t.errors.on(:title)
+    assert_equal "can't be empty", t.errors.on(:content)
+    
+    t.title = "something"
+    t.content  = "another"
+    
+    assert t.save
   end
 end
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