Add #clone. Closes #7352 [Ryan Daigle, thechrisoshow]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9121 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

2 files changed, 72 insertions, 0 deletions

diff --git a/activeresource/lib/active_resource/base.rb b/activeresource/lib/active_resource/base.rb
index 37e77d4f93..d854b9baed 100644
--- a/activeresource/lib/active_resource/base.rb
+++ b/activeresource/lib/active_resource/base.rb
@@ -606,6 +606,43 @@ module ActiveResource
       load(attributes)
     end
 
+    # Returns a clone of the resource that hasn't been assigned an id yet and
+    # is treated as a new resource.
+    #
+    #  ryan = Person.find(1)
+    #  not_ryan = ryan.clone
+    #  not_ryan.new?  # => true
+    #
+    # Any active resource member attributes will NOT be cloned, though all other
+    # attributes are.  This is to prevent the conflict between any prefix_options
+    # that refer to the original parent resource and the newly cloned parent
+    # resource that does not exist.
+    #
+    #  ryan = Person.find(1)
+    #  ryan.address = StreetAddress.find(1, :person_id => ryan.id)
+    #  ryan.hash = {:not => "an ARes instance"}
+    #
+    #  not_ryan = ryan.clone
+    #  not_ryan.new?            # => true
+    #  not_ryan.address         # => NoMethodError
+    #  not_ryan.hash            # => {:not => "an ARes instance"}
+    #
+    def clone
+      # Clone all attributes except the pk and any nested ARes
+      attrs = self.attributes.reject {|k,v| k == self.class.primary_key || v.is_a?(ActiveResource::Base)}.inject({}) do |attrs, (k, v)|
+        attrs[k] = v.clone
+        attrs
+      end
+      # Form the new resource - bypass initialize of resource with 'new' as that will call 'load' which
+      # attempts to convert hashes into member objects and arrays into collections of objects.  We want
+      # the raw objects to be cloned so we bypass load by directly setting the attributes hash.
+      resource = self.class.new({})
+      resource.prefix_options = self.prefix_options
+      resource.send :instance_variable_set, '@attributes', attrs
+      resource
+    end
+
+
     # A method to determine if the resource a new object (i.e., it has not been POSTed to the remote service yet).
     #
     # ==== Examples
diff --git a/activeresource/test/base_test.rb b/activeresource/test/base_test.rb
index 13709f1ca1..9caca803b7 100644
--- a/activeresource/test/base_test.rb
+++ b/activeresource/test/base_test.rb
@@ -558,6 +558,41 @@ class BaseTest < Test::Unit::TestCase
     assert_raises(ActiveResource::ResourceConflict) { Person.create(:name => 'Rick') }
   end
 
+  def test_clone
+   matz = Person.find(1)
+   matz_c = matz.clone
+   assert matz_c.new?
+   matz.attributes.each do |k, v|
+     assert_equal v, matz_c.send(k) if k != Person.primary_key
+   end
+ end
+
+ def test_nested_clone
+   addy = StreetAddress.find(1, :params => {:person_id => 1})
+   addy_c = addy.clone
+   assert addy_c.new?
+   addy.attributes.each do |k, v|
+     assert_equal v, addy_c.send(k) if k != StreetAddress.primary_key
+   end
+   assert_equal addy.prefix_options, addy_c.prefix_options
+ end
+
+ def test_complex_clone
+   matz = Person.find(1)
+   matz.address = StreetAddress.find(1, :params => {:person_id => matz.id})
+   matz.non_ar_hash = {:not => "an ARes instance"}
+   matz.non_ar_arr = ["not", "ARes"]
+   matz_c = matz.clone
+   assert matz_c.new?
+   assert_raises(NoMethodError) {matz_c.address}
+   assert_equal matz.non_ar_hash, matz_c.non_ar_hash
+   assert_equal matz.non_ar_arr, matz_c.non_ar_arr
+
+   # Test that actual copy, not just reference copy
+   matz.non_ar_hash[:not] = "changed"
+   assert_not_equal matz.non_ar_hash, matz_c.non_ar_hash
+ end
+
   def test_update
     matz = Person.find(:first)
     matz.name = "David"