Dashes now raises NoMethodError when reading a non-existent property

2 files changed, 19 insertions, 7 deletions

diff --git a/lib/hashie/dash.rb b/lib/hashie/dash.rb
index eac2293..47b0afe 100644
--- a/lib/hashie/dash.rb
+++ b/lib/hashie/dash.rb
@@ -71,18 +71,24 @@ module Hashie
 
     # Retrieve a value from the Dash (will return the
     # property's default value if it hasn't been set).
-    def [](property_name)
-      super(property_name.to_sym)
+    def [](property)
+      super(property.to_sym) if property_exists? property
     end
 
     # Set a value on the Dash in a Hash-like way. Only works
     # on pre-existing properties.
     def []=(property, value)
-      if self.class.property?(property.to_sym)
-        super
-      else
-        raise NoMethodError, "The property '#{property}' is not defined for this Dash."
-      end
+      super if property_exists? property
     end
+    
+    private 
+      # Raises an NoMethodError if the property doesn't exist
+      #
+      def property_exists?(property)
+        unless self.class.property?(property.to_sym)
+          raise NoMethodError, "The property '#{property}' is not defined for this Dash."
+        end
+        true
+      end
   end
 end
diff --git a/spec/hashie/dash_spec.rb b/spec/hashie/dash_spec.rb
index 3a71c59..9443ef6 100644
--- a/spec/hashie/dash_spec.rb
+++ b/spec/hashie/dash_spec.rb
@@ -32,6 +32,12 @@ describe Hashie::Dash do
     end
   end
   
+  describe 'reading properties' do
+    it 'should raise an error when reading a non-existent property' do 
+      lambda{@dash['abc']}.should raise_error(NoMethodError)
+    end
+  end
+  
   describe ' writing to properties' do
     before do
       @dash = DashTest.new