close #438; PaperTrail::Model::ClassMethods#paper_trail_enabled_for_m…

…odel? should return false if has_paper_trail isn't declared on the class in question

CHANGELOG.md

@@ -5,6 +5,8 @@
 PaperTrail::Rails::Engine.eager_load!
 ```
 
+  - [#438](https://github.com/airblade/paper_trail/issues/438) - `Model.paper_trail_enabled_for_model?` should return `false` if
+    `has_paper_trail` has not been declared on the class.
   - [#427](https://github.com/airblade/paper_trail/pull/427) - Fix `reify` method in context of model where a column has been removed.
   - [#414](https://github.com/airblade/paper_trail/issues/414) - Fix functionality `ignore` argument to `has_paper_trail`
     in `ActiveRecord` 4.

lib/paper_trail/has_paper_trail.rb

@@ -101,6 +101,7 @@ def paper_trail_on
       end
 
       def paper_trail_enabled_for_model?
+        return false unless self.include?(PaperTrail::Model::InstanceMethods)
         PaperTrail.enabled_for_model?(self)
       end
 

spec/models/fluxor_spec.rb

@@ -0,0 +1,19 @@
+require 'rails_helper'
+
+describe Fluxor, :type => :model do
+  describe '`be_versioned` matcher' do
+    it { is_expected.to_not be_versioned }
+  end
+
+  describe "Methods" do
+    describe "Class" do
+      subject { Fluxor }
+
+      describe "#paper_trail_enabled_for_model?" do
+        it { is_expected.to respond_to(:paper_trail_enabled_for_model?) }
+
+        it { expect(subject.paper_trail_enabled_for_model?).to be false }
+      end
+    end
+  end
+end

spec/models/gadget_spec.rb

@@ -1,7 +1,7 @@
 require 'rails_helper'
 
 describe Gadget, :type => :model do
-  it { should be_versioned }
+  it { is_expected.to be_versioned }
 
   let(:gadget) { Gadget.create!(:name => 'Wrench', :brand => 'Acme') }
 

spec/models/widget_spec.rb

@@ -2,7 +2,7 @@
 
 describe Widget, :type => :model do
   describe '`be_versioned` matcher' do
-    it { should be_versioned }
+    it { is_expected.to be_versioned }
   end
 
   let(:widget) { Widget.create! :name => 'Bob', :an_integer => 1 }
@@ -225,6 +225,12 @@
     describe "Class" do
       subject { Widget }
 
+      describe "#paper_trail_enabled_for_model?" do
+        it { is_expected.to respond_to(:paper_trail_enabled_for_model?) }
+
+        it { expect(subject.paper_trail_enabled_for_model?).to be true }
+      end
+
       describe '#paper_trail_off!' do
         it { is_expected.to respond_to(:paper_trail_off!) }
 

test/dummy/app/models/post.rb

@@ -1,4 +1,3 @@
 class Post < ActiveRecord::Base
   has_paper_trail :class_name => "PostVersion"
-
 end