1 files changed, 33 insertions, 0 deletions
diff --git a/activesupport/test/core_ext/object/acts_like_test.rb b/activesupport/test/core_ext/object/acts_like_test.rb
new file mode 100644
index 0000000000..e68b1d23cb
--- /dev/null
+++ b/activesupport/test/core_ext/object/acts_like_test.rb
@@ -0,0 +1,33 @@
+require 'abstract_unit'
+require 'active_support/core_ext/object'
+
+class ObjectTests < ActiveSupport::TestCase
+  class DuckTime
+    def acts_like_time?
+      true
+    end
+  end
+
+  def test_duck_typing
+    object = Object.new
+    time   = Time.now
+    date   = Date.today
+    dt     = DateTime.new
+    duck   = DuckTime.new
+
+    assert !object.acts_like?(:time)
+    assert !object.acts_like?(:date)
+
+    assert time.acts_like?(:time)
+    assert !time.acts_like?(:date)
+
+    assert !date.acts_like?(:time)
+    assert date.acts_like?(:date)
+
+    assert dt.acts_like?(:time)
+    assert dt.acts_like?(:date)
+
+    assert duck.acts_like?(:time)
+    assert !duck.acts_like?(:date)
+  end
+end