image_compare.rb in capybara-screenshot-diff-0.12.1

- old
+ new

@@ -34,12 +34,14 @@
         # Compare the two image files and return `true` or `false` as quickly as possible.
         # Return falsish if the old file does not exist or the image dimensions do not match.
         def quick_equal?
           return nil unless old_file_exists?
           return true if new_file_size == old_file_size
+
           old_bytes, new_bytes = load_image_files(@old_file_name, @new_file_name)
           return true if old_bytes == new_bytes
+
           images = load_images(old_bytes, new_bytes)
           old_bytes = new_bytes = nil # rubocop: disable Lint/UselessAssignment
           crop_images(images, @dimensions) if @dimensions
 
           return false if sizes_changed?(*images)
@@ -145,10 +147,12 @@
         end
 
         def calculate_max_color_distance(new_image, old_image)
           pixel_pairs = old_image.pixels.zip(new_image.pixels)
           @max_color_distance = pixel_pairs.inject(0) do |max, (p1, p2)|
+            next max unless p1 && p2
+
             d = ChunkyPNG::Color.euclidean_distance_rgba(p1, p2)
             [max, d].max
           end
         end
 
@@ -192,10 +196,11 @@
           [old_file, new_file]
         end
 
         def sizes_changed?(org_image, new_image)
           return unless org_image.dimension != new_image.dimension
+
           change_msg = [org_image, new_image].map { |i| "#{i.width}x#{i.height}" }.join(' => ')
           puts "Image size has changed for #{@new_file_name}: #{change_msg}"
           true
         end
 
@@ -237,10 +242,11 @@
           left = @left || old_img.width - 1
           right = @right || 0
           old_img.height.times do |y|
             (0...left).find do |x|
               next if same_color?(old_img, new_img, x, y)
+
               top ||= y
               bottom = y
               left = x
               right = x if x > right
               x
@@ -273,10 +279,11 @@
             @max_color_distance = color_distance
           end
           color_matches = color_distance == 0 || (@color_distance_limit && @color_distance_limit > 0 &&
               color_distance <= @color_distance_limit)
           return color_matches if !@shift_distance_limit || @max_shift_distance == Float::INFINITY
+
           shift_distance =
             if color_matches
               0
             else
               shift_distance_at(new_img, old_img, x, y, color_distance_limit: @color_distance_limit)
@@ -352,17 +359,19 @@
               else
                 bounds_breached += 1
               end
             end
             break if bounds_breached == 4
+
             shift_distance += 1
           end
           Float::INFINITY
         end
 
         def color_matches(new_img, org_color, dx, dy, color_distance_limit)
           new_color = new_img[dx, dy]
           return new_color == org_color unless color_distance_limit
+
           color_distance = ChunkyPNG::Color.euclidean_distance_rgba(org_color, new_color)
           color_distance <= color_distance_limit
         end
       end
     end