1 files changed, 10 insertions, 7 deletions
diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index 50a96bce98..5d784ceb31 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -4,9 +4,10 @@ require "rack/session/abstract/id"
 require "active_support/core_ext/hash/conversions"
 require "active_support/core_ext/object/to_query"
 require "active_support/core_ext/module/anonymous"
+require "active_support/core_ext/module/redefine_method"
 require "active_support/core_ext/hash/keys"
 require "active_support/testing/constant_lookup"
-require_relative "template_assertions"
+require "action_controller/template_assertions"
 require "rails-dom-testing"
 
 module ActionController
@@ -19,7 +20,7 @@ module ActionController
     # the database on the main thread, so they could open a txn, then the
     # controller thread will open a new connection and try to access data
     # that's only visible to the main thread's txn. This is the problem in #23483.
-    remove_method :new_controller_thread
+    silence_redefinition_of_method :new_controller_thread
     def new_controller_thread # :nodoc:
       yield
     end
@@ -255,7 +256,7 @@ module ActionController
   #
   #   def test_create
   #     json = {book: { title: "Love Hina" }}.to_json
-  #     post :create, json
+  #     post :create, body: json
   #   end
   #
   # == Special instance variables
@@ -459,10 +460,6 @@ module ActionController
       def process(action, method: "GET", params: {}, session: nil, body: nil, flash: {}, format: nil, xhr: false, as: nil)
         check_required_ivars
 
-        if body
-          @request.set_header "RAW_POST_DATA", body
-        end
-
         http_method = method.to_s.upcase
 
         @html_document = nil
@@ -477,6 +474,10 @@ module ActionController
         @response.request = @request
         @controller.recycle!
 
+        if body
+          @request.set_header "RAW_POST_DATA", body
+        end
+
         @request.set_header "REQUEST_METHOD", http_method
 
         if as
@@ -603,6 +604,8 @@ module ActionController
           env.delete "action_dispatch.request.query_parameters"
           env.delete "action_dispatch.request.request_parameters"
           env["rack.input"] = StringIO.new
+          env.delete "CONTENT_LENGTH"
+          env.delete "RAW_POST_DATA"
           env
         end