find_or_create_by_* takes a hash so you can create with more attributes than...

find_or_create_by_* takes a hash so you can create with more attributes than are in the method name. Closes #7368.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6420 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

 *SVN*
 
+* find_or_create_by_* takes a hash so you can create with more attributes than are in the method name. For example, Person.find_or_create_by_name(:name => 'Henry', :comments => 'Hi new user!') is equivalent to Person.find_by_name('Henry') || Person.create(:name => 'Henry', :comments => 'Hi new user!').  #7368 [Josh Susser]
+
 * Make sure with_scope takes both :select and :joins into account when setting :readonly.  Allows you to save records you retrieve using method_missing on a has_many :through associations.  [Koz]
 
 * Allow a polymorphic :source for has_many :through associations.  Closes #7143 [protocool]

activerecord/lib/active_record/base.rb

@@ -188,6 +188,13 @@ def initialize(errors)
   #   winter = Tag.find_or_initialize_by_name("Winter")
   #   winter.new_record? # true
   #
+  # To find by a subset of the attributes to be used for instantiating a new object, pass a hash instead of
+  # a list of parameters. For example:
+  #
+  #   Tag.find_or_create_by_name(:name => "rails", :creator => current_user)
+  #
+  # That will either find an existing tag named "rails", or create a new one while setting the user that created it.
+  #
   # == Saving arrays, hashes, and other non-mappable objects in text columns
   #
   # Active Record can serialize any object in text columns using YAML. To do so, you must specify this with a call to the class method +serialize+.
@@ -1254,8 +1261,13 @@ def method_missing(method_id, *arguments)
             attribute_names = extract_attribute_names_from_match(match)
             super unless all_attributes_exists?(attribute_names)
 
-            attributes = construct_attributes_from_arguments(attribute_names, arguments)
-            options = { :conditions => attributes }
+            if arguments[0].is_a?(Hash)
+              attributes = arguments[0].with_indifferent_access
+              find_attributes = attributes.slice(*attribute_names)
+            else
+              find_attributes = attributes = construct_attributes_from_arguments(attribute_names, arguments)
+            end
+            options = { :conditions => find_attributes }
             set_readonly_option!(options)
 
             find_initial(options) || send(instantiator, attributes)

activerecord/test/finder_test.rb

@@ -385,6 +385,17 @@ def test_find_or_create_from_two_attributes
     assert !another.new_record?
   end
   
+  def test_find_or_create_from_one_attribute_and_hash
+    number_of_companies = Company.count
+    sig38 = Company.find_or_create_by_name({:name => "38signals", :firm_id => 17, :client_of => 23})
+    assert_equal number_of_companies + 1, Company.count
+    assert_equal sig38, Company.find_or_create_by_name({:name => "38signals", :firm_id => 17, :client_of => 23})
+    assert !sig38.new_record?
+    assert_equal "38signals", sig38.name
+    assert_equal 17, sig38.firm_id
+    assert_equal 23, sig38.client_of
+  end
+
   def test_find_or_initialize_from_one_attribute
     sig38 = Company.find_or_initialize_by_name("38signals")
     assert_equal "38signals", sig38.name
@@ -397,6 +408,14 @@ def test_find_or_initialize_from_two_attributes
     assert_equal "John", another.author_name
     assert another.new_record?
   end
+  
+  def test_find_or_initialize_from_one_attribute_and_hash
+    sig38 = Company.find_or_initialize_by_name({:name => "38signals", :firm_id => 17, :client_of => 23})
+    assert_equal "38signals", sig38.name
+    assert_equal 17, sig38.firm_id
+    assert_equal 23, sig38.client_of
+    assert sig38.new_record?
+  end
 
   def test_find_with_bad_sql
     assert_raises(ActiveRecord::StatementInvalid) { Topic.find_by_sql "select 1 from badtable" }