Add specs for Struct#deconstruct

core/struct/deconstruct_spec.rb

@@ -0,0 +1,12 @@
+require_relative '../../spec_helper'
+
+ruby_version_is "2.7" do
+  describe "Struct#deconstruct" do
+    it "returns an array of attribute values" do
+      struct = Struct.new(:x, :y)
+      s = struct.new(1, 2)
+
+      s.deconstruct.should == [1, 2]
+    end
+  end
+end