Added can_test? mehod to Service model and added tests

app/models/service.rb

@@ -49,4 +49,8 @@ class Service < ActiveRecord::Base
   def execute
     # implement inside child
   end
+
+  def can_test?
+    !project.empty_repo?
+  end
 end

app/views/projects/services/_form.html.haml

@@ -44,5 +44,5 @@
   .form-actions
     = f.submit 'Save', class: 'btn btn-save'
      
-    - if @service.valid? && @service.activated?
+    - if @service.valid? && @service.activated? && @service.can_test?
       = link_to 'Test settings', test_project_service_path(@project, @service.to_param), class: 'btn btn-small'

spec/models/service_spec.rb

@@ -18,6 +18,7 @@
 require 'spec_helper'
 
 describe Service do
+
   describe "Associations" do
     it { should belong_to :project }
     it { should have_one :service_hook }
@@ -26,4 +27,40 @@ describe Service do
   describe "Mass assignment" do
     it { should_not allow_mass_assignment_of(:project_id) }
   end
+
+  describe "Test Button" do
+    before do
+      @service = Service.new
+    end
+
+    describe "Testable" do
+      let (:project) { create :project }
+
+      before do
+        @service.stub(
+          project: project
+        )
+        @testable = @service.can_test?
+      end
+
+      describe :can_test do
+        it { @testable.should == false }
+      end
+    end
+
+    describe "With commits" do
+      let (:project) { create :project_with_code }
+
+      before do
+        @service.stub(
+          project: project
+        )
+        @testable = @service.can_test?
+      end
+
+      describe :can_test do
+        it { @testable.should == true }
+      end
+    end
+  end
 end