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.

5 files changed, 12 insertions, 16 deletions

diff --git a/actionpack/lib/action_dispatch/routing/mapper.rb b/actionpack/lib/action_dispatch/routing/mapper.rb
index 4c2a4cfeb0..8ff3b42a40 100644
--- a/actionpack/lib/action_dispatch/routing/mapper.rb
+++ b/actionpack/lib/action_dispatch/routing/mapper.rb
@@ -120,7 +120,7 @@ module ActionDispatch
 
           if options_constraints.is_a?(Hash)
             @defaults = Hash[options_constraints.find_all { |key, default|
-              URL_OPTIONS.include?(key) && (String === default || Fixnum === default)
+              URL_OPTIONS.include?(key) && (String === default || Integer === default)
             }].merge @defaults
             @blocks = blocks
             constraints.merge! options_constraints
@@ -824,7 +824,7 @@ module ActionDispatch
 
           if options[:constraints].is_a?(Hash)
             defaults = options[:constraints].select do |k, v|
-              URL_OPTIONS.include?(k) && (v.is_a?(String) || v.is_a?(Fixnum))
+              URL_OPTIONS.include?(k) && (v.is_a?(String) || v.is_a?(Integer))
             end
 
             options[:defaults] = defaults.merge(options[:defaults] || {})
diff --git a/actionpack/lib/action_dispatch/testing/assertion_response.rb b/actionpack/lib/action_dispatch/testing/assertion_response.rb
index 3fb81ff083..404b96bbcd 100644
--- a/actionpack/lib/action_dispatch/testing/assertion_response.rb
+++ b/actionpack/lib/action_dispatch/testing/assertion_response.rb
@@ -1,14 +1,7 @@
 module ActionDispatch
-  # This is a class that abstracts away an asserted response.
-  # It purposely does not inherit from Response, because it doesn't need it.
-  # That means it does not have headers or a body.
-  #
-  # As an input to the initializer, we take a Fixnum, a String, or a Symbol.
-  # If it's a Fixnum or String, we figure out what its symbolized name.
-  # If it's a Symbol, we figure out what its corresponding code is.
-  # The resulting code will be a Fixnum, for real HTTP codes, and it will
-  # be a String for the pseudo-HTTP codes, such as:
-  #   :success, :missing, :redirect and :error
+  # This is a class that abstracts away an asserted response. It purposely
+  # does not inherit from Response because it doesn't need it. That means it
+  # does not have headers or a body.
   class AssertionResponse
     attr_reader :code, :name
 
@@ -19,6 +12,9 @@ module ActionDispatch
       error: "5XX"
     }
 
+    # Accepts a specific response status code as an Integer (404) or String
+    # ('404') or a response status range as a Symbol pseudo-code (:success,
+    # indicating any 200-299 status code).
     def initialize(code_or_name)
       if code_or_name.is_a?(Symbol)
         @name = code_or_name
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(