Merge c697b8a into fce93b1

README.md

@@ -52,7 +52,7 @@ Simply add schema_validations to your Gemfile.
 ```ruby
 gem "schema_validations"
 ```
-    
+
 ## Which validations are covered?
 
 Constraints:
@@ -88,7 +88,7 @@ SchemaValidations.setup do |config|
     # Whether to automatically create validations based on database constraints.
     # (Can be set false globally to disable the gem by default, and set true per-model to enable.)
     config.auto_create = true
-    
+
     # Restricts the set of field names to include in automatic validation.
     # Value is a single name, an array of names, or nil.
     config.only = nil
@@ -97,26 +97,29 @@ SchemaValidations.setup do |config|
     # Value is a single type, an array of types, or nil.
     # A type is specified as, e.g., `:validates_presence_of` or simply `:presence`.
     config.only_type = nil
-    
+
     # A list of field names to exclude from automatic validation.
     # Value is a single name, an array of names, or nil.
     # (Providing a value per-model will completely replace a globally-configured list)
     config.except = nil
-    
+
     # A list of validation types to exclude from automatic validation.
     # Value is a single type, an array of types, or nil.
     # (Providing a value per-model will completely replace a globally-configured list)
     config.except_type = nil
-       
+
     # The base set of field names to always exclude from automatic validation.
     # Value is a single name, an array of names, or nil.
     # (This whitelist applies after all other considerations, global or per-model)
     config.whitelist = [:created_at, :updated_at, :created_on, :updated_on]
-       
+
     # The base set of validation types to always exclude from automatic validation.
     # Value is a single type, an array of types, or nil.
     # (This whitelist applies after all other considerations, global or per-model)
     config.whitelist_type = nil
+
+    # Whether to check if the column has changed before validating uniqueness.
+    config.uniqueness_if_changed = true
 end
 ```    
 

lib/schema_validations.rb

@@ -74,6 +74,13 @@ class Config < Valuable
     # A type is specified as, e.g., +:validates_presence_of+ or simply +:presence+.
     has_value :only_type, :default => nil
 
+    ##
+    # :attr_accessor: uniqueness_if_changed
+    #
+    # Whether to check if the column has changed before validating uniqueness.
+    # Boolean, default is +true+.
+    has_value :uniqueness_if_changed, :klass => :boolean, :default => true
+
     def dup #:nodoc:
       self.class.new(Hash[attributes.collect{ |key, val| [key, Valuable === val ?  val.class.new(val.attributes) : val] }])
     end

lib/schema_validations/active_record/validations.rb

@@ -175,13 +175,15 @@ def add_uniqueness_validation(column) #:nodoc:
           options[:scope] = scope if scope.any?
           options[:allow_nil] = true
           options[:case_sensitive] = false if has_case_insensitive_index?(column, scope)
-          options[:if] = (proc do |record|
-            if scope.all? { |scope_sym| record.public_send(:"#{scope_sym}?") }
-              record.public_send(:"#{column.name}_changed?")
-            else
-              false
-            end
-          end)
+          if schema_validations_config.uniqueness_if_changed
+            options[:if] = (proc do |record|
+              if scope.all? { |scope_sym| record.public_send(:"#{scope_sym}?") }
+                record.public_send(:"#{column.name}_changed?")
+              else
+                false
+              end
+            end)
+          end
 
           validate_logged :validates_uniqueness_of, name, options
         end