Merge pull request #1470 from rspec/remove_legacy_formatter_support

Remove support for inherited legacy formatters [WIP]

Author: myronmarston

features/command_line/require_option.feature

@@ -10,6 +10,8 @@ Feature: `--require` option
       require 'delegate'
 
       class LoggingFormatter < RSpec::Core::Formatters::BaseTextFormatter
+        RSpec::Core::Formatters.register self, :dump_summary
+
         def initialize(output)
           super LoggingIO.new(output)
         end

features/formatters/custom_formatter.feature

@@ -38,30 +38,3 @@ Feature: custom formatters
     When I run `rspec example_spec.rb --require ./custom_formatter.rb --format CustomFormatter`
     Then the output should contain "example: my example"
     And  the exit status should be 0
-
-  Scenario: A legacy custom formatter
-    Given a file named "custom_formatter.rb" with:
-      """ruby
-      require "rspec/core/formatters/base_text_formatter"
-
-      class CustomFormatter < RSpec::Core::Formatters::BaseTextFormatter
-        def initialize(output)
-          super(output)
-        end
-
-        def example_started(proxy)
-          output << "example: " << proxy.description
-        end
-      end
-      """
-    And a file named "example_spec.rb" with:
-      """ruby
-      RSpec.describe "my group" do
-        specify "my example" do
-        end
-      end
-      """
-    When I run `rspec example_spec.rb --require ./custom_formatter.rb --format CustomFormatter`
-    Then the output should contain "example: my example"
-    And the output should contain "The CustomFormatter formatter uses the deprecated formatter interface."
-    And  the exit status should be 0

features/formatters/regression_tests.feature

@@ -1,5 +1,3 @@
-RSpec::Support.require_rspec_core 'formatters/legacy_formatter'
-
 # ## Built-in Formatters
 #
 # * progress (default) - prints dots for passing examples, `F` for failures, `*` for pending
@@ -116,16 +114,32 @@ def add(formatter_to_use, *paths)
       if !Loader.formatters[formatter_class].nil?
         formatter = formatter_class.new(*args)
         @reporter.register_listener formatter, *notifications_for(formatter_class)
-      else
-        formatter = LegacyFormatter.new(formatter_class, *args)
+      elsif defined?(RSpec::LegacyFormatters)
+        formatter = RSpec::LegacyFormatters.load_formatter formatter_class, *args
         @reporter.register_listener formatter, *formatter.notifications
-      end
+      else
+        line = ::RSpec::CallerFilter.first_non_rspec_line
+        if line
+          call_site = "Formatter added at: #{line}"
+        else
+          call_site = "The formatter was added via command line flag or your "+
+                      "`.rspec` file."
+        end
 
-      @formatters << formatter unless duplicate_formatter_exists?(formatter)
-      if formatter.is_a?(LegacyFormatter)
-        RSpec.warn_deprecation "The #{formatter_class} formatter uses the deprecated formatter interface.\n Formatter added at: #{::RSpec::CallerFilter.first_non_rspec_line}"
+        RSpec.warn_deprecation <<-WARNING.gsub(/\s*\|/,' ')
+          |The #{formatter_class} formatter uses the deprecated formatter
+          |interface not supported directly by RSpec 3.
+          |
+          |To continue to use this formatter you must install the
+          |`rspec-legacy_formatters` gem, which provides support
+          |for legacy formatters or upgrade the formatter to a
+          |compatible version.
+          |
+          |#{call_site}
+        WARNING
+        return
       end
-
+      @formatters << formatter unless duplicate_formatter_exists?(formatter)
       formatter
     end