diff.rb in capybara-screenshot-diff-1.6.3

- old
+ new

@@ -50,29 +50,24 @@
       mattr_accessor :color_distance_limit
       mattr_accessor(:enabled) { true }
       mattr_accessor :shift_distance_limit
       mattr_accessor :skip_area
       mattr_accessor(:driver) { :auto }
-      mattr_accessor(:tolerance) { 0.001 }
+      mattr_accessor :tolerance
 
       AVAILABLE_DRIVERS = Utils.detect_available_drivers.freeze
-      begin
-        require "minitest"
-        ASSERTION = Minitest::Assertion
-      rescue
-        ASSERTION = RuntimeError
-      end
+      ASSERTION = Utils.detect_test_framework_assert
 
       def self.default_options
         {
           area_size_limit: area_size_limit,
           color_distance_limit: color_distance_limit,
           driver: driver,
           shift_distance_limit: shift_distance_limit,
           skip_area: skip_area,
           stability_time_limit: Screenshot.stability_time_limit,
-          tolerance: tolerance,
+          tolerance: tolerance || (driver == :vips ? 0.001 : nil),
           wait: Capybara.default_max_wait_time
         }
       end
 
       def self.included(klass)
@@ -87,22 +82,34 @@
           end
         end
 
         klass.teardown do
           if Capybara::Screenshot.active? && @test_screenshots
-            test_screenshot_errors = @test_screenshots
-              .map { |caller, name, compare| assert_image_not_changed(caller, name, compare) }
-            @test_screenshots = nil # release the comparison objects from memory
-            test_screenshot_errors.compact!
-            if test_screenshot_errors.any?
-              e = ASSERTION.new(test_screenshot_errors.join("\n\n"))
-              e.set_backtrace(caller)
-              if defined?(failures)
-                failures << e
-              else
-                raise e
-              end
-            end
+            track_failures(@test_screenshots, caller)
+            @test_screenshots = nil
+          end
+        end
+      end
+
+      private
+
+      EMPTY_LINE = "\n\n"
+
+      def track_failures(screenshots, original_caller)
+        test_screenshot_errors = screenshots.map do |caller, name, compare|
+          assert_image_not_changed(caller, name, compare)
+        end
+
+        test_screenshot_errors.compact!
+
+        unless test_screenshot_errors.empty?
+          error = ASSERTION.new(test_screenshot_errors.join(EMPTY_LINE))
+          error.set_backtrace(original_caller)
+
+          if is_a?(::Minitest::Runnable)
+            failures << error
+          else
+            raise error
           end
         end
       end
     end
   end