Added specs

spec/models/variable_spec.rb

+# == Schema Information
+#
+# Table name: variables
+#
+#  id                   :integer          not null, primary key
+#  project_id           :integer          not null
+#  key                  :string(255)
+#  value                :text
+#  encrypted_value      :string(255)
+#  encrypted_value_salt :string(255)
+#  encrypted_value_iv   :string(255)
+#
+
+require 'spec_helper'
+
+describe Variable do
+  subject { Variable.new }
+
+  let(:secret_value) { 'secret' }
+
+  before :each do
+    subject.value = secret_value
+  end
+
+  describe :value do
+    it 'stores the encrypted value' do
+      subject.encrypted_value.should_not be_nil
+    end
+
+    it 'stores an iv for value' do
+      subject.encrypted_value_iv.should_not be_nil
+    end
+
+    it 'stores a salt for value' do
+      subject.encrypted_value_salt.should_not be_nil
+    end
+
+    it 'fails to decrypt if iv is incorrect' do
+      subject.encrypted_value_iv = nil
+      subject.instance_variable_set(:@value, nil)
+      expect { subject.value }.to raise_error
+    end
+  end
+end