Use :skip instead of :if/:unless

spec/rspec/support/source/node_spec.rb

@@ -1,7 +1,7 @@
 require 'rspec/support/source/node'
 
 class RSpec::Support::Source
-  RSpec.describe Node, :if => RSpec::Support::RubyFeatures.ripper_supported? do
+  RSpec.describe Node, :skip => !RSpec::Support::RubyFeatures.ripper_supported? do
     let(:root_node) do
       Node.new(sexp)
     end

spec/rspec/support/source/token_spec.rb

@@ -1,7 +1,7 @@
 require 'rspec/support/source/token'
 
 class RSpec::Support::Source
-  RSpec.describe Token, :if => RSpec::Support::RubyFeatures.ripper_supported? do
+  RSpec.describe Token, :skip => !RSpec::Support::RubyFeatures.ripper_supported? do
     let(:target_token) do
       tokens.first
     end

spec/rspec/support/source_spec.rb

@@ -1,7 +1,7 @@
 require 'rspec/support/source'
 
 module RSpec::Support
-  RSpec.describe Source, :if => RSpec::Support::RubyFeatures.ripper_supported? do
+  RSpec.describe Source, :skip => !RSpec::Support::RubyFeatures.ripper_supported? do
     subject(:source) do
       Source.new(source_string)
     end