8 files changed, 22 insertions, 10 deletions
diff --git a/actionpack/lib/action_controller/metal/redirecting.rb b/actionpack/lib/action_controller/metal/redirecting.rb
index 4dfcf4da28..a349841082 100644
--- a/actionpack/lib/action_controller/metal/redirecting.rb
+++ b/actionpack/lib/action_controller/metal/redirecting.rb
@@ -56,7 +56,7 @@ module ActionController
 
       self.status        = _extract_redirect_to_status(options, response_status)
       self.location      = _compute_redirect_to_location(request, options)
-      self.response_body = "<html><body>You are being <a href=\"#{ERB::Util.unwrapped_html_escape(location)}\">redirected</a>.</body></html>"
+      self.response_body = "<html><body>You are being <a href=\"#{ERB::Util.unwrapped_html_escape(response.location)}\">redirected</a>.</body></html>"
     end
 
     # Redirects the browser to the page that issued the request (the referrer)
diff --git a/actionpack/lib/action_dispatch/system_test_case.rb b/actionpack/lib/action_dispatch/system_test_case.rb
index 276e3161bd..59faf63ce3 100644
--- a/actionpack/lib/action_dispatch/system_test_case.rb
+++ b/actionpack/lib/action_dispatch/system_test_case.rb
@@ -36,7 +36,7 @@ module ActionDispatch
     #     end
     #   end
     #
-    # When generating an application or scaffold a +application_system_test_case.rb+
+    # When generating an application or scaffold, an +application_system_test_case.rb+
     # file will also be generated containing the base class for system testing.
     # This is where you can change the driver, add Capybara settings, and other
     # configuration for your system tests.
diff --git a/actionpack/test/controller/redirect_test.rb b/actionpack/test/controller/redirect_test.rb
index e4e968dfdb..f06a1f4d23 100644
--- a/actionpack/test/controller/redirect_test.rb
+++ b/actionpack/test/controller/redirect_test.rb
@@ -21,8 +21,8 @@ end
 class RedirectController < ActionController::Base
   # empty method not used anywhere to ensure methods like
   # `status` and `location` aren't called on `redirect_to` calls
-  def status; render plain: "called status"; end
-  def location; render plain: "called location"; end
+  def status; raise "Should not be called!"; end
+  def location; raise "Should not be called!"; end
 
   def simple_redirect
     redirect_to action: "hello_world"
diff --git a/guides/source/testing.md b/guides/source/testing.md
index c7897a42a1..113314a5b8 100644
--- a/guides/source/testing.md
+++ b/guides/source/testing.md
@@ -636,11 +636,11 @@ change the default settings.
 Rails makes changing the default settings for system test very simple. All
 the setup is abstracted away so you can focus on writing your tests.
 
-When you generate a new application or scaffold, a `application_system_test_case.rb` file
+When you generate a new application or scaffold, an `application_system_test_case.rb` file
 is created in the test directory. This is where all the configuration for your
 system tests should live.
 
-If you want to change the default settings you can simple change what the system
+If you want to change the default settings you can simply change what the system
 tests are "driven by". Say you want to change the driver from Selenium to
 Poltergeist. First add the Poltergeist gem to your Gemfile. Then in your
 `application_system_test_case.rb` file do the following:
@@ -685,7 +685,7 @@ This can be helpful for viewing the browser at the point a test failed, or
 to view screenshots later for debugging.
 
 Two methods are provided: `take_screenshot` and `take_failed_screenshot`.
-`take_failed_screenshot` is automatically included in  `after_teardown` inside
+`take_failed_screenshot` is automatically included in `after_teardown` inside
 Rails.
 
 The `take_screenshot` helper method can be included anywhere in your tests to
diff --git a/railties/lib/rails/generators/app_base.rb b/railties/lib/rails/generators/app_base.rb
index e55da93f45..f365ad05c7 100644
--- a/railties/lib/rails/generators/app_base.rb
+++ b/railties/lib/rails/generators/app_base.rb
@@ -193,7 +193,7 @@ module Rails
       def webserver_gemfile_entry # :doc:
         return [] if options[:skip_puma]
         comment = "Use Puma as the app server"
-        GemfileEntry.new("puma", "~> 3.0", comment)
+        GemfileEntry.new("puma", "~> 3.7", comment)
       end
 
       def include_all_railties? # :doc:
diff --git a/railties/lib/rails/test_unit/minitest_plugin.rb b/railties/lib/rails/test_unit/minitest_plugin.rb
index 7d3da6b529..e44fe78bbd 100644
--- a/railties/lib/rails/test_unit/minitest_plugin.rb
+++ b/railties/lib/rails/test_unit/minitest_plugin.rb
@@ -115,7 +115,9 @@ module Minitest
     alias set? runner
 
     # Backwardscompatibility with Rails 5.0 generated plugin test scripts.
-    alias []= runner=
+    def []=(runner, *)
+      @runner = runner
+    end
 
     def ruby?
       runner == :ruby
diff --git a/railties/test/application/test_runner_test.rb b/railties/test/application/test_runner_test.rb
index d3d5b6d6dd..ee03d8b86c 100644
--- a/railties/test/application/test_runner_test.rb
+++ b/railties/test/application/test_runner_test.rb
@@ -15,6 +15,16 @@ module ApplicationTests
       teardown_app
     end
 
+    def test_run_via_backwardscompatibility
+      require "rails/test_unit/minitest_plugin"
+
+      assert_nothing_raised do
+        Minitest.run_via[:ruby] = true
+      end
+
+      assert_predicate Minitest.run_via, :ruby?
+    end
+
     def test_run_single_file
       create_test_file :models, "foo"
       create_test_file :models, "bar"
diff --git a/railties/test/generators/app_generator_test.rb b/railties/test/generators/app_generator_test.rb
index 687aed2c47..bd1b412b36 100644
--- a/railties/test/generators/app_generator_test.rb
+++ b/railties/test/generators/app_generator_test.rb
@@ -340,7 +340,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
 
   def test_generator_defaults_to_puma_version
     run_generator [destination_root]
-    assert_gem "puma", "'~> 3.0'"
+    assert_gem "puma", "'~> 3.7'"
   end
 
   def test_generator_if_skip_puma_is_given