Create new polymorphic model Document.

spec/factories.rb

@@ -368,6 +368,18 @@ FactoryGirl.define do
     end
   end
 
+  factory :document do
+    association :user, factory: :user
+
+    trait :proposal_document do
+      association :documentable, factory: :proposal
+    end
+
+    trait :budget_investment_document do
+      association :documentable, factory: :budget_investment
+    end
+  end
+
   factory :comment do
     association :commentable, factory: :debate
     user

spec/models/document_spec.rb

@@ -0,0 +1,8 @@
+require 'rails_helper'
+
+describe Document do
+
+  it_behaves_like "document validations", "budget_investment_document"
+  it_behaves_like "document validations", "proposal_document"
+
+end

spec/shared/models/document_validatable.rb

@@ -0,0 +1,27 @@
+shared_examples "document validations" do |documentable_factory|
+
+  let(:documentable) { build(:document, documentable_factory.to_sym) }
+
+  it "should be valid" do
+    expect(documentable).to be_valid
+  end
+
+  it "should not be valid without a user_id" do
+    documentable.user_id = nil
+
+    expect(documentable).to_not be_valid
+  end
+
+  it "should not be valid without a documentable_id" do
+    documentable.documentable_id = nil
+
+    expect(documentable).to_not be_valid
+  end
+
+  it "should not be valid without a documentable_type" do
+    documentable.documentable_type = nil
+
+    expect(documentable).to_not be_valid
+  end
+
+end