Added a safety guard for double wrapping.

lib/recursive_open_struct.rb

@@ -29,6 +29,7 @@ def self.default_options
   end
 
   def initialize(hash=nil, passed_options={})
+    hash = hash.to_h if [hash.is_a?(RecursiveOpenStruct), hash.is_a?(OpenStruct)].any?
     hash ||= {}
 
     @options = self.class.default_options.merge!(passed_options).freeze

spec/recursive_open_struct/wrapping_spec.rb

@@ -0,0 +1,70 @@
+require_relative '../spec_helper'
+require 'recursive_open_struct'
+
+describe RecursiveOpenStruct do
+  describe 'wrapping RecursiveOpenStruct' do
+    let(:h) { { :blah => { :another => 'value' } } }
+    subject(:ros) { RecursiveOpenStruct.new(RecursiveOpenStruct.new(h)) }
+
+    it 'can convert the entire hash tree back into a hash' do
+      expect(ros.to_h).to eq h
+    end
+
+    it 'can access the flat keys' do
+      expect(ros.blah).to be_a(RecursiveOpenStruct)
+    end
+
+    it 'can access the nested keys' do
+      expect(ros.blah.another).to eql('value')
+    end
+
+    it 'can be inspected' do
+      expect(ros.inspect).to \
+        match(/#<RecursiveOpenStruct blah={:?another(: |=>)"value"}>/)
+    end
+  end
+
+  describe 'wrapping OpenStruct' do
+    let(:h) { { :blah => { :another => 'value' } } }
+    subject(:ros) { RecursiveOpenStruct.new(OpenStruct.new(h)) }
+
+    it 'can convert the entire hash tree back into a hash' do
+      expect(ros.to_h).to eq h
+    end
+
+    it 'can access the flat keys' do
+      expect(ros.blah).to be_a(RecursiveOpenStruct)
+    end
+
+    it 'can access the nested keys' do
+      expect(ros.blah.another).to eql('value')
+    end
+
+    it 'can be inspected' do
+      expect(ros.inspect).to \
+        match(/#<RecursiveOpenStruct blah={:?another(: |=>)"value"}>/)
+    end
+  end
+
+  describe 'wrapping a subclass' do
+    let(:h) { { :blah => { :another => 'value' } } }
+    let(:subclass) { Class.new(RecursiveOpenStruct) }
+    subject(:ros) { subclass.new(subclass.new(h)) }
+
+    it 'can convert the entire hash tree back into a hash' do
+      expect(ros.to_h).to eq h
+    end
+
+    it 'can access the flat keys' do
+      expect(ros.blah).to be_a(RecursiveOpenStruct)
+    end
+
+    it 'can access the nested keys' do
+      expect(ros.blah.another).to eql('value')
+    end
+
+    it 'can be inspected' do
+      expect(ros.inspect).to match(/ blah={:?another(: |=>)"value"}>$/)
+    end
+  end
+end