Fix issue #33 DSL object is replaced when #dsl_eval is nested (PR #34)

* add examples for #33

* fix #33

* added workaround RSpec's issue
rspec/rspec-expectations#1111

Thanks @taichi-ishitani !

docile.gemspec

@@ -31,6 +31,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency "rake", "~> 10.5" if on_less_than_1_9_3? # Pin compatible rake on old rubies, see: https://github.com/travis-ci/travis.rb/issues/380
   s.add_development_dependency "rake", "< 11.0"  unless on_less_than_1_9_3? # See http://stackoverflow.com/questions/35893584/nomethoderror-undefined-method-last-comment-after-upgrading-to-rake-11
   s.add_development_dependency "rspec", "~> 3.0"
+  s.add_development_dependency "rspec-expectations", "!= 3.8.3" # Workaround for RSpec's issue, see: https://github.com/rspec/rspec-expectations/issues/1111
 
   # Run code coverage where possible - not on Rubinius
   unless on_rubinius?

lib/docile/fallback_context_proxy.rb

@@ -54,7 +54,7 @@ def initialize(receiver, fallback)
         singleton_class.
           send(:define_method, :method_missing) do |method, *args, &block|
             m = method.to_sym
-            if !NON_FALLBACK_METHODS.include?(m) && receiver.respond_to?(m)
+            if !NON_FALLBACK_METHODS.include?(m) && !fallback.respond_to?(m) && receiver.respond_to?(m)
               receiver.__send__(method.to_sym, *args, &block)
             else
               super(method, *args, &block)

spec/docile_spec.rb

@@ -68,12 +68,15 @@ def execute_dsl_against_builder_and_call_build
     class InnerDSL
       def initialize; @b = "b"; end
       attr_accessor :b
+      def c; "inner c"; end
     end
 
     class OuterDSL
       def initialize; @a = "a"; end
       attr_accessor :a
 
+      def c; "outer c"; end
+
       def inner(&block)
         Docile.dsl_eval(InnerDSL.new, &block)
       end
@@ -226,24 +229,26 @@ def push_element
       context "method lookup" do
         it "finds method of outer dsl in outer dsl scope" do
           outer { expect(a).to eq("a") }
+          outer { inner {}; expect(c).to eq("outer c") }
         end
 
         it "finds method of inner dsl in inner dsl scope" do
           outer { inner { expect(b).to eq("b") } }
+          outer { inner { expect(c).to eq("inner c") } }
         end
 
         it "finds method of outer dsl in inner dsl scope" do
           outer { inner { expect(a).to eq("a") } }
         end
 
         it "finds method of block's context in outer dsl scope" do
-          def c; "c"; end
-          outer { expect(c).to eq("c") }
+          def d; "d"; end
+          outer { expect(d).to eq("d") }
         end
 
         it "finds method of block's context in inner dsl scope" do
-          def c; "c"; end
-          outer { inner { expect(c).to eq("c") } }
+          def d; "d"; end
+          outer { inner { expect(d).to eq("d") } }
         end
 
         it "finds method of outer dsl in preference to block context" do