Added #has_only_roles? and #is_exactly? methods.

lib/role_model/implementation.rb

@@ -44,5 +44,20 @@ module RoleModel
     alias_method :is_any_of?, :has_any_role?
     alias_method :has_role?, :has_any_role?
 
+    # :call-seq:
+    #   has_only_roles?(:role)
+    #   has_only_roles?('role')
+    #   has_only_roles?(:role_1, ..., :role_n)
+    #   has_only_roles?('role_1', ..., 'role_n')
+    #   has_only_roles?([:role_1, ..., :role_n])
+    #   has_only_roles?(['role_1', ..., 'role_n'])
+    #
+    # check if ONLY of the given roles have been assigned
+    # this method is aliased as #is_exactly?
+    def has_only_roles?(*roles)
+      self.send("#{self.class.roles_attribute_name}") == self.class.mask_for(*roles)
+    end
+    alias_method :is_exactly?, :has_only_roles?
+
   end
 end

spec/role_model_spec.rb

@@ -318,6 +318,11 @@ describe RoleModel do
       describe "##{check_role_assignment_method}" do
         subject { model_class.new }
 
+        it "returns true when the assigned roles include the given roles" do
+          subject.roles = [:foo, :bar, :third]
+          subject.send(check_role_assignment_method, :foo, :bar).should be_true
+        end
+
         it "should return true when all of the given roles were assigned" do
           subject.roles = [:foo, :bar]
           subject.send(check_role_assignment_method, :foo, :bar).should be_true
@@ -336,6 +341,29 @@ describe RoleModel do
     end
   end
 
+  context "query for exact roles" do
+    [:has_only_roles?, :is_exactly?].each do |check_role_assignment_method|
+      describe "##{check_role_assignment_method}" do
+        subject { model_class.new }
+
+        it "returns false when the given roles are a subset of those assigned" do
+          subject.roles = [:foo, :bar, :third]
+          subject.send(check_role_assignment_method, :foo, :bar).should be_false
+        end
+
+        it "returns true when the given roles exactly match those assigned" do
+          subject.roles = [:foo, :bar]
+          subject.send(check_role_assignment_method, :foo, :bar).should be_true
+        end
+
+        it "should return false when only some of the given roles were assigned" do
+          subject.roles = [:foo, :bar]
+          subject.send(check_role_assignment_method, :bar, :baz).should be_false
+        end
+      end
+    end
+  end
+
   context "query for roles when none defined in model" do
     [:has_any_role?, :is_any_of?, :has_role?, :has_all_roles?, :is?, :has_roles?].each do |check_role_assignment_method|
       describe "##{check_role_assignment_method}" do