"Use assert_nil if expecting nil. This will fail in minitest 6."

Author: amatsuda

actionpack/test/controller/integration_test.rb

@@ -289,7 +289,7 @@ def test_post
       assert_response :success
       assert_equal "bar", body
 
-      assert_equal nil, headers["Set-Cookie"]
+      assert_nil headers["Set-Cookie"]
       assert_equal({ "foo" => "bar" }, cookies.to_hash)
     end
   end
@@ -308,7 +308,7 @@ def test_post
       assert_response :success
       assert_equal "bar", body
 
-      assert_equal nil, headers["Set-Cookie"]
+      assert_nil headers["Set-Cookie"]
       assert_equal({ "foo" => "bar" }, cookies.to_hash)
     end
   end

actionpack/test/controller/new_base/bare_metal_test.rb

@@ -52,7 +52,7 @@ class BareEmptyTest < ActiveSupport::TestCase
       controller.set_request!(ActionDispatch::Request.empty)
       controller.set_response!(BareController.make_response!(controller.request))
       controller.index
-      assert_equal nil, controller.response_body
+      assert_nil controller.response_body
     end
   end
 

actionpack/test/controller/new_base/render_streaming_test.rb

@@ -101,12 +101,12 @@ class StreamingTest < Rack::TestCase
       assert_body "Hello world, I'm here!"
       assert_status 200
       assert_equal "22", headers["Content-Length"]
-      assert_equal nil, headers["Transfer-Encoding"]
+      assert_nil headers["Transfer-Encoding"]
     end
 
     def assert_streaming!(cache = "no-cache")
       assert_status 200
-      assert_equal nil, headers["Content-Length"]
+      assert_nil headers["Content-Length"]
       assert_equal "chunked", headers["Transfer-Encoding"]
       assert_equal cache, headers["Cache-Control"]
     end

actionpack/test/controller/parameters/parameters_permit_test.rb

@@ -141,7 +141,7 @@ def walk_permitted(params)
     permitted = params.permit(:a, c: [], b: [])
     assert_equal 1, permitted[:a]
     assert_equal [1, 2, 3], permitted[:b]
-    assert_equal nil, permitted[:c]
+    assert_nil permitted[:c]
   end
 
   test "key to empty array: arrays of permitted scalars pass" do
@@ -216,7 +216,7 @@ def walk_permitted(params)
   test "fetch with a default value of a hash does not mutate the object" do
     params = ActionController::Parameters.new({})
     params.fetch :foo, {}
-    assert_equal nil, params[:foo]
+    assert_nil params[:foo]
   end
 
   test "hashes in array values get wrapped" do
@@ -254,8 +254,8 @@ def walk_permitted(params)
   end
 
   test "fetch doesnt raise ParameterMissing exception if there is a default that is nil" do
-    assert_equal nil, @params.fetch(:foo, nil)
-    assert_equal nil, @params.fetch(:foo) { nil }
+    assert_nil @params.fetch(:foo, nil)
+    assert_nil @params.fetch(:foo) { nil }
   end
 
   test "KeyError in fetch block should not be covered up" do

actionpack/test/controller/request/test_request_test.rb

@@ -8,7 +8,7 @@ def test_test_request_has_session_options_initialized
 
   def test_mutating_session_options_does_not_affect_default_options
     @request.session_options[:myparam] = 123
-    assert_equal nil, ActionController::TestSession::DEFAULT_OPTIONS[:myparam]
+    assert_nil ActionController::TestSession::DEFAULT_OPTIONS[:myparam]
   end
 
   def test_content_length_has_bytes_count_value

actionpack/test/dispatch/cookies_test.rb

@@ -944,8 +944,8 @@ def test_legacy_signed_cookie_is_treated_as_nil_by_signed_cookie_jar_if_tampered
     @request.headers["Cookie"] = "user_id=45"
     get :get_signed_cookie
 
-    assert_equal nil, @controller.send(:cookies).signed[:user_id]
-    assert_equal nil, @response.cookies["user_id"]
+    assert_nil @controller.send(:cookies).signed[:user_id]
+    assert_nil @response.cookies["user_id"]
   end
 
   def test_legacy_signed_cookie_is_treated_as_nil_by_encrypted_cookie_jar_if_tampered
@@ -955,8 +955,8 @@ def test_legacy_signed_cookie_is_treated_as_nil_by_encrypted_cookie_jar_if_tampe
     @request.headers["Cookie"] = "foo=baz"
     get :get_encrypted_cookie
 
-    assert_equal nil, @controller.send(:cookies).encrypted[:foo]
-    assert_equal nil, @response.cookies["foo"]
+    assert_nil @controller.send(:cookies).encrypted[:foo]
+    assert_nil @response.cookies["foo"]
   end
 
   def test_cookie_with_all_domain_option

actionpack/test/dispatch/request/multipart_params_parsing_test.rb

@@ -129,7 +129,7 @@ def teardown
     params = parse_multipart("none")
     assert_equal %w(submit-name), params.keys.sort
     assert_equal "Larry", params["submit-name"]
-    assert_equal nil, params["files"]
+    assert_nil params["files"]
   end
 
   test "parses empty upload file" do

actionpack/test/dispatch/request_test.rb

@@ -94,13 +94,13 @@ class RequestIP < BaseRequestTest
     assert_equal "3.4.5.6", request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "unknown,192.168.0.1"
-    assert_equal nil, request.remote_ip
+    assert_nil request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "9.9.9.9, 3.4.5.6, 172.31.4.4, 10.0.0.1"
     assert_equal "3.4.5.6", request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "not_ip_address"
-    assert_equal nil, request.remote_ip
+    assert_nil request.remote_ip
   end
 
   test "remote ip spoof detection" do
@@ -154,7 +154,7 @@ class RequestIP < BaseRequestTest
     assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "unknown,::1"
-    assert_equal nil, request.remote_ip
+    assert_nil request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "2001:0db8:85a3:0000:0000:8a2e:0370:7334, fe80:0000:0000:0000:0202:b3ff:fe1e:8329, ::1, fc00::, fc01::, fdff"
     assert_equal "fe80:0000:0000:0000:0202:b3ff:fe1e:8329", request.remote_ip
@@ -163,7 +163,7 @@ class RequestIP < BaseRequestTest
     assert_equal "FE00::", request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "not_ip_address"
-    assert_equal nil, request.remote_ip
+    assert_nil request.remote_ip
   end
 
   test "remote ip v6 spoof detection" do
@@ -200,7 +200,7 @@ class RequestIP < BaseRequestTest
     assert_equal "3.4.5.6", request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "67.205.106.73,unknown"
-    assert_equal nil, request.remote_ip
+    assert_nil request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "9.9.9.9, 3.4.5.6, 10.0.0.1, 67.205.106.73"
     assert_equal "3.4.5.6", request.remote_ip
@@ -222,7 +222,7 @@ class RequestIP < BaseRequestTest
     assert_equal "::1", request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "unknown,fe80:0000:0000:0000:0202:b3ff:fe1e:8329"
-    assert_equal nil, request.remote_ip
+    assert_nil request.remote_ip
 
     request = stub_request "HTTP_X_FORWARDED_FOR" => "fe80:0000:0000:0000:0202:b3ff:fe1e:8329,2001:0db8:85a3:0000:0000:8a2e:0370:7334"
     assert_equal "2001:0db8:85a3:0000:0000:8a2e:0370:7334", request.remote_ip
@@ -345,7 +345,7 @@ class RequestPort < BaseRequestTest
 
   test "optional port" do
     request = stub_request "HTTP_HOST" => "www.example.org:80"
-    assert_equal nil, request.optional_port
+    assert_nil request.optional_port
 
     request = stub_request "HTTP_HOST" => "www.example.org:8080"
     assert_equal 8080, request.optional_port
@@ -537,7 +537,7 @@ class RequestCGI < BaseRequestTest
 
     assert_equal "Basic", request.auth_type
     assert_equal 0, request.content_length
-    assert_equal nil, request.content_mime_type
+    assert_nil request.content_mime_type
     assert_equal "CGI/1.1", request.gateway_interface
     assert_equal "*/*", request.accept
     assert_equal "UTF-8", request.accept_charset
@@ -957,7 +957,7 @@ class RequestMimeType < BaseRequestTest
   end
 
   test "no content type" do
-    assert_equal nil, stub_request.content_mime_type
+    assert_nil stub_request.content_mime_type
   end
 
   test "content type is XML" do
@@ -978,7 +978,7 @@ class RequestMimeType < BaseRequestTest
       "HTTP_X_REQUESTED_WITH" => "XMLHttpRequest"
     )
 
-    assert_equal nil, request.negotiate_mime([Mime[:xml], Mime[:json]])
+    assert_nil request.negotiate_mime([Mime[:xml], Mime[:json]])
     assert_equal Mime[:html], request.negotiate_mime([Mime[:xml], Mime[:html]])
     assert_equal Mime[:html], request.negotiate_mime([Mime[:xml], Mime::ALL])
   end
@@ -1192,7 +1192,7 @@ class RequestEtag < BaseRequestTest
   test "doesn't match absent If-None-Match" do
     request = stub_request
 
-    assert_equal nil, request.if_none_match
+    assert_nil request.if_none_match
     assert_equal [], request.if_none_match_etags
 
     assert_not request.etag_matches?("foo")

actionpack/test/dispatch/response_test.rb

@@ -74,7 +74,7 @@ def test_read_body_during_action
     @response.body = "Hello, World!"
 
     # even though there's no explicitly set content-type,
-    assert_equal nil, @response.content_type
+    assert_nil @response.content_type
 
     # after the action reads back @response.body,
     assert_equal "Hello, World!", @response.body
@@ -112,7 +112,7 @@ def test_setting_content_type_header_impacts_content_type_method
 
   def test_empty_content_type_returns_nil
     @response.headers['Content-Type'] = ""
-    assert_equal nil, @response.content_type
+    assert_nil @response.content_type
   end
 
   test "simple output" do

actionpack/test/dispatch/routing_test.rb

@@ -4189,7 +4189,7 @@ def app; APP end
 
   test "parameters are reset between constraint checks" do
     get "/bar"
-    assert_equal nil, @request.params[:foo]
+    assert_nil @request.params[:foo]
     assert_equal "bar", @request.params[:bar]
   end
 end