Merge pull request drapergem#251 from WizardOfOgz/feature-denies-all

Add denies_all feature

lib/draper/base.rb

@@ -105,6 +105,16 @@ def self.denies(*input_denied)
       self.denied += input_denied
     end
 
+    # Specifies that all methods may *not* be proxied to
+    # to the wrapped object.
+    #
+    # Do not use `.allows` and `.denies` in combination with '.denies_all'
+    def self.denies_all
+      raise ArgumentError, "Use either 'allows' or 'denies', but not both." unless ((self.allowed == DEFAULT_ALLOWED && self.denied == DEFAULT_DENIED) || (self.allowed != DEFAULT_ALLOWED && self.denied != DEFAULT_DENIED))
+      self.denied  += [nil]  # Add dummy value to denied to prevent calls to #allows.  Hacky???
+      self.allowed += [nil]  # Add dummy value to allowed to prevent calls to #denies
+    end
+
     # Specifies a white list of methods which *may* be proxied to
     # to the wrapped object. When `allows` is used, only the listed
     # methods and methods defined in the decorator itself will be

spec/draper/base_spec.rb

@@ -693,6 +693,69 @@ class DecoratorWithDeniesAndAllows < Draper::Base
     end
   end
 
+  describe "a sample usage with denies_all" do
+    let(:subject_with_denies_all){ DecoratorWithDeniesAll.new(source) }
+
+    [:goodnight_moon, :hello_world, :title].each do |method|
+      it "does echo #{method} method" do
+        subject_with_denies_all.should_not respond_to(method)
+      end
+    end
+
+    let(:using_denies_all_then_denies_all) {
+      class DecoratorWithDeniesAllAndDeniesAll < Draper::Base
+        denies_all
+        denies_all
+      end
+    }
+
+    it "allows multple calls to .denies_all" do
+      expect { using_denies_all_then_denies_all }.to_not raise_error(ArgumentError)
+    end
+  end
+
+  describe "invalid usages of denies_all" do
+    let(:using_allows_then_denies_all) {
+      class DecoratorWithAllowsAndDeniesAll < Draper::Base
+        allows :hello_world
+        denies_all
+      end
+    }
+    let(:using_denies_then_denies_all) {
+      class DecoratorWithDeniesAndDeniesAll < Draper::Base
+        denies :goodnight_moon
+        denies_all
+      end
+    }
+    let(:using_denies_all_then_allows) {
+      class DecoratorWithDeniesAllAndAllows < Draper::Base
+        denies_all
+        allows :hello_world
+      end
+    }
+    let(:using_denies_all_then_denies) {
+      class DecoratorWithDeniesAllAndDenies < Draper::Base
+        denies_all
+        denies :goodnight_moon
+      end
+    }
+    it "raises an exception when calling allows then denies_all" do
+      expect {using_allows_then_denies_all}.to raise_error(ArgumentError)
+    end
+
+    it "raises an exception when calling denies then denies_all" do
+      expect {using_denies_then_denies_all}.to raise_error(ArgumentError)
+    end
+
+    it "raises an exception when calling denies_all then allows" do
+      expect {using_denies_all_then_allows}.to raise_error(ArgumentError)
+    end
+
+    it "raises an exception when calling denies_all then denies" do
+      expect {using_denies_all_then_denies}.to raise_error(ArgumentError)
+    end
+  end
+
   context "in a Rails application" do
     let(:decorator){ DecoratorWithApplicationHelper.decorate(Object.new) }
 

spec/spec_helper.rb

@@ -15,6 +15,7 @@
 require './spec/support/samples/decorator_with_multiple_allows'
 require './spec/support/samples/decorator_with_application_helper'
 require './spec/support/samples/decorator_with_denies'
+require './spec/support/samples/decorator_with_denies_all'
 require './spec/support/samples/decorator_with_special_methods'
 require './spec/support/samples/namespaced_product'
 require './spec/support/samples/namespaced_product_decorator'

spec/support/samples/decorator_with_denies_all.rb

@@ -0,0 +1,3 @@
+class DecoratorWithDeniesAll < Draper::Base
+  denies_all
+end