Add implicit receiver support to `Object#with_options`

3 files changed, 29 insertions, 2 deletions

diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index 2a53fa95c1..61e9927a07 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,3 +1,8 @@
+*   `Object#with_options` executes block in merging option context when
+    explicit receiver in not passed.
+
+    *Pavel Pravosud*
+
 *   Fixed a compatibility issue with the `Oj` gem when cherry-picking the file
     `active_support/core_ext/object/json` without requiring `active_support/json`.
 
diff --git a/activesupport/lib/active_support/core_ext/object/with_options.rb b/activesupport/lib/active_support/core_ext/object/with_options.rb
index 42e388b065..42e87c4424 100644
--- a/activesupport/lib/active_support/core_ext/object/with_options.rb
+++ b/activesupport/lib/active_support/core_ext/object/with_options.rb
@@ -34,9 +34,22 @@ class Object
   #     body    i18n.t :body, user_name: user.name
   #   end
   #
+  # When you don't pass an explicit receiver, it executes the whole block
+  # in merging options context:
+  #
+  #   class Account < ActiveRecord::Base
+  #     with_options dependent: :destroy do
+  #       has_many :customers
+  #       has_many :products
+  #       has_many :invoices
+  #       has_many :expenses
+  #     end
+  #   end
+  #
   # <tt>with_options</tt> can also be nested since the call is forwarded to its receiver.
   # Each nesting level will merge inherited defaults in addition to their own.
-  def with_options(options)
-    yield ActiveSupport::OptionMerger.new(self, options)
+  def with_options(options, &block)
+    option_merger = ActiveSupport::OptionMerger.new(self, options)
+    block.arity.zero? ? option_merger.instance_eval(&block) : block.call(option_merger)
   end
 end
diff --git a/activesupport/test/option_merger_test.rb b/activesupport/test/option_merger_test.rb
index 9d139b61b8..4c0364e68b 100644
--- a/activesupport/test/option_merger_test.rb
+++ b/activesupport/test/option_merger_test.rb
@@ -79,6 +79,15 @@ class OptionMergerTest < ActiveSupport::TestCase
     assert_equal ActiveSupport::OptionMerger, ActiveSupport::OptionMerger.new('', '').class
   end
 
+  def test_option_merger_implicit_receiver
+    @options.with_options foo: "bar" do
+      merge! fizz: "buzz"
+    end
+
+    expected = { hello: "world", foo: "bar", fizz: "buzz" }
+    assert_equal expected, @options
+  end
+
   private
     def method_with_options(options = {})
       options