Also allow yielding the context

2 files changed, 19 insertions, 1 deletions

diff --git a/lib/mixlib/config.rb b/lib/mixlib/config.rb
index 0da23b7..c039364 100644
--- a/lib/mixlib/config.rb
+++ b/lib/mixlib/config.rb
@@ -460,7 +460,12 @@ module Mixlib
       meta.send :define_method, symbol do |*args, &block|
         # If a block was given, eval it in the context
         if block
-          context_eval(symbol, &block)
+          # If the block expects no arguments, then instance_eval
+          if block.arity == 0
+            context_eval(symbol, &block)
+          else # yield to the block
+            context_yield(symbol, &block)
+          end
         else
           internal_get_or_set(symbol, *args)
         end
@@ -470,5 +475,9 @@ module Mixlib
     def context_eval(context, &block)
       internal_get(context).instance_eval(&block)
     end
+
+    def context_yield(context)
+      yield internal_get(context)
+    end
   end
 end
diff --git a/spec/mixlib/config_spec.rb b/spec/mixlib/config_spec.rb
index 1ea8d02..f6b2b1c 100644
--- a/spec/mixlib/config_spec.rb
+++ b/spec/mixlib/config_spec.rb
@@ -763,6 +763,15 @@ describe Mixlib::Config do
       @klass.blah.y.should == 20
     end
 
+    it "setting the context values in a yielded block overrides the default values" do
+      @klass.blah do |b|
+        b.x = 10
+        b.y = 20
+      end
+      @klass.blah.x.should == 10
+      @klass.blah.y.should == 20
+    end
+
     it "after reset of the parent class, children are reset" do
       @klass.blah.x = 10
       @klass.blah.x.should == 10