Support for unified Integer class in Ruby 2.4+

Ruby 2.4 unifies Fixnum and Bignum into Integer: https://bugs.ruby-lang.org/issues/12005

* Forward compat with new unified Integer class in Ruby 2.4+.
* Backward compat with separate Fixnum/Bignum in Ruby 2.2 & 2.3.
* Drops needless Fixnum distinction in docs, preferring Integer.

3 files changed, 4 insertions, 4 deletions

diff --git a/actionpack/test/assertions/response_assertions_test.rb b/actionpack/test/assertions/response_assertions_test.rb
index 579ce0ed29..57a67a48b5 100644
--- a/actionpack/test/assertions/response_assertions_test.rb
+++ b/actionpack/test/assertions/response_assertions_test.rb
@@ -35,7 +35,7 @@ module ActionDispatch
         end
       end
 
-      def test_assert_response_fixnum
+      def test_assert_response_integer
         @response = FakeResponse.new 400
         assert_response 400
 
diff --git a/actionpack/test/controller/routing_test.rb b/actionpack/test/controller/routing_test.rb
index 168677829a..03bf8f8295 100644
--- a/actionpack/test/controller/routing_test.rb
+++ b/actionpack/test/controller/routing_test.rb
@@ -626,7 +626,7 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
     assert_equal '/pages/boo', url_for(rs, { :controller => 'pages', :action => 'boo' })
   end
 
-  def test_route_with_fixnum_default
+  def test_route_with_integer_default
     rs.draw do
       get 'page(/:id)' => 'content#show_page', :id => 1
 
diff --git a/actionpack/test/controller/test_case_test.rb b/actionpack/test/controller/test_case_test.rb
index ebcdda6074..6160b3395a 100644
--- a/actionpack/test/controller/test_case_test.rb
+++ b/actionpack/test/controller/test_case_test.rb
@@ -553,7 +553,7 @@ XML
     assert_equal 'created', flash[:notice]
   end
 
-  def test_params_passing_with_fixnums
+  def test_params_passing_with_integer
     get :test_params, params: {
       page: { name: "Page name", month: 4, year: 2004, day: 6 }
     }
@@ -565,7 +565,7 @@ XML
     )
   end
 
-  def test_params_passing_with_fixnums_when_not_html_request
+  def test_params_passing_with_integers_when_not_html_request
     get :test_params, params: { format: 'json', count: 999 }
     parsed_params = ::JSON.parse(@response.body)
     assert_equal(