Add testcase for invalid color

app/models/label.rb

@@ -3,10 +3,12 @@ class Label < ActiveRecord::Base
   has_many :label_links, dependent: :destroy
   has_many :issues, through: :label_links, source: :target, source_type: 'Issue'
 
-  validates :color, format: { with: /\A\#[0-9A-Fa-f]{6}+\Z/ }, allow_blank: true
+  validates :color,
+            format: { with: /\A\#[0-9A-Fa-f]{6}+\Z/ },
+            allow_blank: false
   validates :project, presence: true
 
-  # Dont allow '?', '&', and ',' for label titles
+  # Don't allow '?', '&', and ',' for label titles
   validates :title, presence: true, format: { with: /\A[^&\?,&]*\z/ }
 
   scope :order_by_name, -> { reorder("labels.title ASC") }

features/project/issues/labels.feature

@@ -23,3 +23,8 @@ Feature: Project Labels
   Scenario: I remove label
     When I remove label 'bug'
     Then I should not see label 'bug'
+
+  Scenario: I create a label with invalid color
+    Given I visit new label page
+    When I submit new label with invalid color
+    Then I should see label color error message

features/steps/project/labels.rb

@@ -31,6 +31,18 @@ class ProjectLabels < Spinach::FeatureSteps
     click_button 'Save'
   end
 
+  step 'I submit new label with invalid color' do
+    fill_in 'Title', with: 'support'
+    fill_in 'Background Color', with: '#12'
+    click_button 'Save'
+  end
+
+  step 'I should see label color error message' do
+    within '.label-form' do
+      page.should have_content 'Color is invalid'
+    end
+  end
+
   step 'I should not see label \'bug\'' do
     within '.manage-labels-list' do
       page.should_not have_content 'bug'