include file comparison and tests

lib/controller/comparer.rb

@@ -4,13 +4,14 @@ class Comparer
 
   attr_accessor :difference
 
-  def initialize(base, new, baseurl, urls, resolutions, screenshot_path)
+  def initialize(base, new, difference_path, baseurl, urls, resolutions, screenshot_path)
     @base = base
     @new = new
     @baseurl = baseurl
     @urls = urls
     @resolutions = resolutions
     @absolute_image_path = screenshot_path
+    @difference_path = difference_path
     compare_images
   end
 
@@ -20,20 +21,21 @@ def compare_images
     self.difference = []
     @urls.each do |page|
       @resolutions.each do |width|
-        puts 'START'
         base_name = Recorder.filename(@absolute_image_path, page, width, @base)
         new_name = Recorder.filename(@absolute_image_path, page, width, @new)
-        puts base_name
-        puts new_name
         images = PXDoppelganger::Images.new(
             base_name,
             new_name
         )
-        puts images.difference
-        images.save_difference_image base_name
-        self.difference << images.difference
+        if images.difference > 1e-05 # for changes bigger than 1 per 10.000; otherwise we see mathematical artifacts
+          diff_name = Recorder.filename(@difference_path, page, width, 'DIFFERENCE')
+          images.save_difference_image diff_name
+          result = [base_name, new_name, diff_name, images.difference]
+          self.difference << result
+        end
       end
     end
+    difference
   end
 
 end

lib/lineup.rb

@@ -4,6 +4,8 @@
 
 module Lineup
 
+  attr_accessor :difference
+
   class Screenshot
 
     def initialize(baseurl)
@@ -12,11 +14,17 @@ def initialize(baseurl)
       resolutions('640, 800, 1180')
       filepath_for_images("#{Dir.pwd}/screenshots")
       use_headless(false)
+      difference_path("#{Dir.pwd}/screenshots")
     end
 
     def urls(urls)
+      raise "url for screenshot cannot be <empty string>" if urls == ''
       raise_base_screenshots_taken('The urls')
-      @urls= urls.gsub(' ', '').split(",")
+      begin
+        @urls= urls.gsub(' ', '').split(",")
+      rescue NoMethodError
+        raise "urls must be in a "
+      end
     end
 
     def resolutions(resolutions)
@@ -41,12 +49,13 @@ def record_screenshot(version)
       @got_base_screenshots = true
     end
 
-    def compare(base, new)
-      Comparer.new(base, new, @baseurl, @urls, @resolutions, @screenshots_path)
+    def difference_path(path)
+      @difference_path = path
     end
 
-    def difference
-
+    def compare(base, new)
+      comparer = Comparer.new(base, new, @difference_path, @baseurl, @urls, @resolutions, @screenshots_path)
+      comparer.difference
     end
 
   private

lib/recorder.rb

@@ -13,15 +13,19 @@ def url(base, url)
 
   def name(page)
     if page == '/'
-      name = 'storefront'
+      name = 'frontpage'
     else #remove forward slash
-      name = page.gsub(/\//, "_")
+      name = page.gsub(/\//, "")
     end
     name
   end
 
   def clean(url)
-    '' if url == '/' #avoid two dashes at the end, e.g. www.otto.de//
+    if url == '/' #avoid two dashes at the end, e.g. www.otto.de//
+      ''
+    else
+      url
+    end
   end
 
 end

tests/rspec/lineup_spec.rb

@@ -1,47 +1,53 @@
 require 'rspec'
 require 'dimensions'
+require 'fileutils'
 require_relative '../../lib/lineup'
 
 describe '#screeshot_recorder' do
 
+  BASE_URL = 'https://www.otto.de'
+  SCREENSHOTS = "#{Dir.pwd}/screenshots/"
+
+  #after(:each) { FileUtils.rmtree SCREENSHOTS }
+
   it 'opens a URL and takes mobile/tablet/desktop screenshots' do
-    lineup = Lineup::Screenshot.new('https://www.otto.de')
+    lineup = Lineup::Screenshot.new(BASE_URL)
     lineup.record_screenshot('base')
 
     expect(
-        File.exist? ("#{Dir.pwd}/screenshots/storefront_640_base.png")
+        File.exist? ("#{Dir.pwd}/screenshots/frontpage_640_base.png")
     ).to be(true)
 
     expect(
-        File.exist? ("#{Dir.pwd}/screenshots/storefront_800_base.png")
+        File.exist? ("#{Dir.pwd}/screenshots/frontpage_800_base.png")
     ).to be(true)
 
     expect(
-        File.exist? ("#{Dir.pwd}/screenshots/storefront_1180_base.png")
+        File.exist? ("#{Dir.pwd}/screenshots/frontpage_1180_base.png")
     ).to be(true)
 
   end
 
   it 'takes a screenshot a desired resolution' do
     width = '320' #min width firefox as of Sep 2015
-    lineup = Lineup::Screenshot.new('https://www.otto.de')
+    lineup = Lineup::Screenshot.new(BASE_URL)
     lineup.resolutions(width)
     lineup.record_screenshot('base')
-    imagewidth = Dimensions.width("#{Dir.pwd}/screenshots/storefront_#{width}_base.png")
+    imagewidth = Dimensions.width("#{Dir.pwd}/screenshots/frontpage_#{width}_base.png")
 
     expect(imagewidth).to be < (width.to_i + 10) #depending on the browser, there may be frames in the window. the screenshot represents the width of the viewport though
 
   end
 
   it 'takes screenshots of different pages, if specified' do
-    urls = '/,multimedia,sport'
-    lineup = Lineup::Screenshot.new('https://www.otto.de')
+    urls = '/, multimedia, sport'
+    lineup = Lineup::Screenshot.new(BASE_URL)
     lineup.urls(urls)
     lineup.resolutions('1180')
     lineup.record_screenshot('base')
 
     expect(
-        File.exist? ("#{Dir.pwd}/screenshots/storefront_1180_base.png")
+        File.exist? ("#{Dir.pwd}/screenshots/frontpage_1180_base.png")
     ).to be(true)
 
     expect(
@@ -51,7 +57,7 @@
   end
 
   it 'raises and exception if, parameters are changed after the base screenshot' do
-    lineup = Lineup::Screenshot.new('https://www.otto.de')
+    lineup = Lineup::Screenshot.new(BASE_URL)
     lineup.urls('/')
     lineup.resolutions('400')
     lineup.record_screenshot('base')
@@ -63,32 +69,33 @@
   end
 
   it 'compares a base and a new screenshot and detects no difference if images are the same' do
-    lineup = Lineup::Screenshot.new('https://www.otto.de')
+    lineup = Lineup::Screenshot.new(BASE_URL)
     lineup.urls('/')
     lineup.resolutions('400')
     lineup.record_screenshot('base')
     lineup.record_screenshot('new')
-    lineup.compare('base', 'new')
     expect(
-      lineup.difference
-    ).to be(nil)
+      lineup.compare('base', 'new')
+    ).to eq([])
 
   end
 
-  it 'compares a base and a new screenshot and returns the difference' do
-    #lineup = Lineup::Screenshot.new('https://www.otto.de')
-    #lineup.urls('/')
-    #lineup.resolutions('400')
-    #lineup.record_screenshot('base')
-    lineup = Lineup::Screenshot.new('https://www.otto.de')
-    lineup.urls('/')
-    lineup.resolutions('400')
-    #lineup.record_screenshot('new')
-    lineup.compare('base', 'new')
-    puts lineup.difference
+  it 'compares a base and a new screenshot and returns the difference if the images are NOT the same' do
+    width = '400'
+    base_site = '/index.html'
+    new_site = '/schwer.html'
+    lineup = Lineup::Screenshot.new(BASE_URL)
+    lineup.urls(base_site)
+    lineup.resolutions(width)
+    lineup.record_screenshot('base')
+    FileUtils.mv "#{Dir.pwd}/screenshots#{base_site}_#{width}_base.png", "#{Dir.pwd}/screenshots#{new_site}_#{width}_base.png"
+    lineup = Lineup::Screenshot.new(BASE_URL)
+    lineup.urls(new_site)
+    lineup.resolutions(width)
+    lineup.record_screenshot('new')
     expect(
-      lineup.difference
-    ).to be(nil)
+        lineup.compare('base', 'new')
+    ).to eq([0])
   end
 
 end