1 files changed, 61 insertions, 0 deletions
diff --git a/activerecord/test/cases/finder_respond_to_test.rb b/activerecord/test/cases/finder_respond_to_test.rb
new file mode 100644
index 0000000000..59af4e6961
--- /dev/null
+++ b/activerecord/test/cases/finder_respond_to_test.rb
@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "models/topic"
+
+class FinderRespondToTest < ActiveRecord::TestCase
+  fixtures :topics
+
+  def test_should_preserve_normal_respond_to_behaviour_on_base
+    assert_respond_to ActiveRecord::Base, :new
+    assert_not_respond_to ActiveRecord::Base, :find_by_something
+  end
+
+  def test_should_preserve_normal_respond_to_behaviour_and_respond_to_newly_added_method
+    class << Topic; self; end.send(:define_method, :method_added_for_finder_respond_to_test) {}
+    assert_respond_to Topic, :method_added_for_finder_respond_to_test
+  ensure
+    class << Topic; self; end.send(:remove_method, :method_added_for_finder_respond_to_test)
+  end
+
+  def test_should_preserve_normal_respond_to_behaviour_and_respond_to_standard_object_method
+    assert_respond_to Topic, :to_s
+  end
+
+  def test_should_respond_to_find_by_one_attribute_before_caching
+    ensure_topic_method_is_not_cached(:find_by_title)
+    assert_respond_to Topic, :find_by_title
+  end
+
+  def test_should_respond_to_find_by_with_bang
+    ensure_topic_method_is_not_cached(:find_by_title!)
+    assert_respond_to Topic, :find_by_title!
+  end
+
+  def test_should_respond_to_find_by_two_attributes
+    ensure_topic_method_is_not_cached(:find_by_title_and_author_name)
+    assert_respond_to Topic, :find_by_title_and_author_name
+  end
+
+  def test_should_respond_to_find_all_by_an_aliased_attribute
+    ensure_topic_method_is_not_cached(:find_by_heading)
+    assert_respond_to Topic, :find_by_heading
+  end
+
+  def test_should_not_respond_to_find_by_one_missing_attribute
+    assert_not_respond_to Topic, :find_by_undertitle
+  end
+
+  def test_should_not_respond_to_find_by_invalid_method_syntax
+    assert_not_respond_to Topic, :fail_to_find_by_title
+    assert_not_respond_to Topic, :find_by_title?
+    assert_not_respond_to Topic, :fail_to_find_or_create_by_title
+    assert_not_respond_to Topic, :find_or_create_by_title?
+  end
+
+  private
+
+    def ensure_topic_method_is_not_cached(method_id)
+      class << Topic; self; end.send(:remove_method, method_id) if Topic.public_methods.include? method_id
+    end
+end