new config mechanism

.gitignore

@@ -19,3 +19,4 @@ artifacts
 *.swp
 .DS_Store
 .env
+.rspec

README.md

@@ -1,4 +1,4 @@
-[![Build Status](https://travis-ci.org/bskyb-commerce/cezanne.svg?branch=master)](https://travis-ci.org/bskyb-commerce/cezanne)
+[![Build Status](https://travis-ci.org/BSkyB/cezanne.svg?branch=master)](https://travis-ci.org/BSkyB/cezanne)
 
 # Cezanne
 
@@ -26,10 +26,14 @@ In your spec_helper.rb
 
     RSpec.configure do |config|
       config.include Cezanne
-      config.cezanne = { uid: ENV['build_number'], project_name: 'awesome_app' }
     end
 
-The uid should be a unique identifier. We use the build number, but it can be a static string if you don't need
+    Cezanne.configure do |config|
+      config.uid = ENV['build_number']
+      config.project_name = 'awesome_app'
+    end
+
+The should be a unique identifier. We use the build number, but it can be a static string if you don't need
 to keep multiple versions of the screenshots.
 
 In your tests
@@ -48,7 +52,7 @@ and the browser name & version, to make it easy to check visual regressions on m
 
 ## Dependencies
 
-Cezanne uses ImageMagick to compare images. Check with your package manager.
+Cezanne uses ImageMagick. Check with your package manager.
 
 Screenshots are stored on Dropbox through the Dropscreen gem. Follow the instructions at https://github.com/bskyb-commerce/dropscreen and make sure to export the access_token
 

cezanne.gemspec

@@ -27,4 +27,5 @@ Gem::Specification.new do |spec|
 
   spec.add_dependency "rmagick"
   spec.add_dependency "dropscreen"
+  spec.add_dependency "phashion"
 end

lib/cezanne.rb

@@ -1,10 +1,12 @@
 require "cezanne/version"
+require "cezanne/config"
 require "cezanne/local_files"
 require "cezanne/remote_files"
 require "cezanne/image"
 require "cezanne/comparison"
 
 module Cezanne
+
 
   def check_visual_regression_for page_name, opts = {}
     screenshot = take_screenshot page_name, opts

lib/cezanne/comparison.rb

@@ -1,14 +1,11 @@
-require 'RMagick'
-
 module Cezanne
 
-  SIMILARITY_THRESHOLD = 42
-
   def spot_differences_between this, that
     width = [this.width, that.width].min
     height = [this.height, that.height].min
     [this, that].each { |img| img.crop!(width, height) }
-    this.picture.compare_channel(that.picture, Magick::PeakSignalToNoiseRatioMetric)[1] < SIMILARITY_THRESHOLD
+
+    not(this.duplicate? that)
   end
 
 end

lib/cezanne/config.rb

@@ -0,0 +1,33 @@
+module Cezanne
+
+  Config = Struct.new(:uid, :project_name, :local_root, :remote_root, :local_files, :remote_files, :comparison_method, :similarity_threshold)  
+
+  def self.config
+    @config ||= Cezanne::Config.new
+  end
+
+
+  def self.configure 
+    config = Cezanne.config 
+
+    yield config if block_given?
+
+    config.comparison_method ||= :peak_signal_to_noise_ratio 
+    config.similarity_threshold ||= (config.comparison_method.eql?(:peak_signal_to_noise_ratio) ? 42 : 15)
+    config.local_root ||= 'artifacts'
+    config.remote_root ||= config.project_name
+    config.local_files ||= Cezanne::LocalFiles.new(config.uid, config.local_root) 
+    config.remote_files ||= Cezanne::RemoteFiles.new(config.uid, config.remote_root) 
+  end
+
+  private
+
+    def local_files 
+      Cezanne.config.local_files
+    end
+
+    def remote_files 
+      Cezanne.config.remote_files
+    end
+
+end

lib/cezanne/image.rb

@@ -1,4 +1,5 @@
 require 'RMagick'
+require 'phashion'
 
 module Cezanne
 
@@ -27,6 +28,23 @@ def width
     def height
       @picture.rows
     end
-  end
 
+    def duplicate? other
+      send(Cezanne.config.comparison_method, other)
+    end
+
+    alias_method :==, :duplicate?
+
+    private 
+
+      def peak_signal_to_noise_ratio other
+        @picture.compare_channel(other.picture, Magick::PeakSignalToNoiseRatioMetric)[1] > Cezanne.config.similarity_threshold
+      end 
+
+      def phash_hamming_distance other 
+        Phashion::Image.new(@path).duplicate? Phashion::Image.new(other.path), threshold: Cezanne.config.similarity_threshold
+      end 
+
+  end
+
 end

lib/cezanne/rspec.rb

@@ -3,41 +3,23 @@
 
 RSpec.configure do |config|
 
-  config.add_setting :cezanne
-
   config.before(:all, screenshots: true) do
     if self.class.include?(Cezanne)
-      uid = config.cezanne[:uid]
-      project_name = config.cezanne[:project_name]
-      config.cezanne[:local_files] = Cezanne::LocalFiles.new(uid, 'artifacts')
-      config.cezanne[:remote_files] = Cezanne::RemoteFiles.new(uid, project_name)
       begin
-        config.cezanne[:remote_files].pull(:ref, config.cezanne[:local_files].path_for(:ref))
+        Cezanne.config.remote_files.pull(:ref, Cezanne.config.local_files.path_for(:ref))
       rescue 
-        puts "no reference screenshot exist for project #{project_name}"
+        puts "no reference screenshot exist for project #{Cezanne.config.project_name}"
       end
     end
   end
 
   config.after(:all, screenshots: true) do
     if self.class.include?(Cezanne)
       [:new, :diff].each do |key|
-        config.cezanne[:remote_files].push(config.cezanne[:local_files].path_for(key), key)
+        Cezanne.config.remote_files.push(Cezanne.config.local_files.path_for(key), key)
       end
-      config.cezanne[:local_files].clean
+      Cezanne.config.local_files.clean
     end
   end
 
 end
-
-module Cezanne
-
-  def local_files
-    RSpec.configuration.cezanne[:local_files]
-  end
-
-  def remote_files
-    RSpec.configuration.cezanne[:remote_files]
-  end
-
-end

lib/cezanne/version.rb

@@ -1,3 +1,3 @@
 module Cezanne
-  VERSION = "0.0.3"
+  VERSION = "0.1.0"
 end

spec/cezanne_image_spec.rb

@@ -12,7 +12,7 @@
     end
 
     it 'return an error if there is no file at path' do
-      expect { Cezanne::Image.new('unexistent_file_path') }.to raise_error
+      expect { Cezanne::Image.new('inexistent_file_path') }.to raise_error
     end
   end
 
@@ -67,4 +67,33 @@
 
   end
 
+  describe '#duplicate?' do 
+    let(:other_image) { double('Cezanne::Image') }
+
+    it 'compare two images' do 
+      Cezanne.config.comparison_method = :comparison_method
+      allow(image).to receive(:comparison_method)
+      expect(image).to receive(:comparison_method).with(other_image)
+      image.duplicate? other_image
+    end 
+
+    it 'can use peak signal to noise ratio' do 
+      Cezanne.config.comparison_method = :peak_signal_to_noise_ratio
+      Cezanne.config.similarity_threshold = 42
+
+      allow(other_image).to receive(:picture)
+      expect(image.picture).to receive(:compare_channel).with(other_image.picture, Magick::PeakSignalToNoiseRatioMetric).and_return([nil, 10])
+      image.duplicate? other_image
+    end
+
+    it 'can use phash hamming distance' do 
+      Cezanne.config.comparison_method = :phash_hamming_distance
+      Cezanne.config.similarity_threshold = 15
+
+      allow(other_image).to receive(:path)
+      expect_any_instance_of(Phashion::Image).to receive(:duplicate?)
+      image.duplicate? other_image
+    end
+
+  end
 end

spec/cezanne_rspec_spec.rb

@@ -1,23 +1,29 @@
 require 'cezanne/rspec'
 require 'capybara/rspec'
 require 'selenium-webdriver'
-require 'pry'
-
 
 Capybara.app = Rack::Directory.new('spec/images')
 Capybara.default_driver = :selenium
 
 RSpec.configure do |config|
   config.include Cezanne
-  config.cezanne = { uid: 'test', project_name: 'cezanne' }
 end
 
 describe 'Cezanne RSpec integration', type: :feature, screenshots: true, integration: true do
-
-  # wrap each test with before(:all) and after(:all) 
+
+  before(:all) do 
+    Cezanne.configure do |config| 
+      config.uid = 'test'
+      config.project_name = 'cezanne'
+    end
+  end  
+
+  # wrap each test with before(:all) and after(:all); since local folders are creted within the Cezanne.configure and
+  # cleaned in a after(:all) hook, we need to tweak that in order for the tests to work 
 
   after(:all) do |example|
     RSpec.configuration.after(:all, screenshots: true).last.instance_variable_set(:@block, Proc.new {}) # disable the after(:all) hook  
+    Cezanne.config.local_files.clean
   end
 
   before(:each) do |example|
@@ -26,13 +32,9 @@
 
   after(:each) do |example|
     RSpec.configuration.after(:all, screenshots: true).last.run(example) unless example.metadata[:after_hook_test] 
+    Cezanne.config.local_files = Cezanne::LocalFiles.new(Cezanne.config.uid, Cezanne.config.local_root) 
   end
 
-
-
-
-
-
   describe 'initialization' do
 
     it 'create local folders' do 
@@ -52,41 +54,55 @@
 
   describe 'take screenshots' do 
 
-    context 'similar' do
+    {phash_hamming_distance: 'phash hamming distance', peak_signal_to_noise_ratio: 'peak signal to noise ratio'}.each do |key, value|
+
+     context value do  
+
+        before(:all) do 
+          Cezanne.configure do |config|
+            config.comparison_method = key
+          end
+        end
 
-      it 'pass the test' do
-        visit '/similar.html'
-        expect { check_visual_regression_for 'similar' }.not_to raise_error
-      end
+        context 'similar' do
 
-    end
-
-    context 'different' do
+          it 'pass the test' do
+            visit '/similar.html'
+            expect { check_visual_regression_for 'similar' }.not_to raise_error
+          end
 
-      it 'fail the test' do
-        visit '/different.html'
-        expect { check_visual_regression_for 'different' }.to raise_error
-      end
+        end
+
+        context 'different' do
 
-    end
+          it 'fail the test' do
+            visit '/different.html'
+            expect { check_visual_regression_for 'different' }.to raise_error
+          end
 
-
-    context 'new' do
+        end
+
+
+        context 'new' do
+
+          it 'fail the test' do
+            visit '/new.html'
+            expect { check_visual_regression_for 'new' }.to raise_error
+          end
+
+        end
 
-      it 'fail the test' do
-        visit '/new.html'
-        expect { check_visual_regression_for 'new' }.to raise_error
       end
 
-    end
+    end 
 
   end
 
   describe 'finalization', after_hook_test: true do
 
     it 'push new, diff screenshots to remote' do |example|
-      expect(RSpec.configuration.cezanne[:remote_files]).to receive('push').with(kind_of(String), :diff).and_call_original
-      expect(RSpec.configuration.cezanne[:remote_files]).to receive('push').with(kind_of(String), :new).and_call_original
+      expect(Cezanne.config.remote_files).to receive('push').with(kind_of(String), :diff).and_call_original
+      expect(Cezanne.config.remote_files).to receive('push').with(kind_of(String), :new).and_call_original
       RSpec.configuration.after(:all, screenshots: true).last.run(example)  
     end