```ruby
# frozen_string_literal: true

#
#  = Functional Test Case
#
#  The test case class that all functional tests currently derive from.
#  Includes:
#
#  1. Some general-purpose helpers and assertions from GeneralExtensions.
#  2. Some controller-related helpers and assertions from ControllerExtensions.
#  3. A few helpers that encapsulate testing the flash error mechanism.
#
################################################################################

class FunctionalTestCase < ActionController::TestCase
  include GeneralExtensions
  include FlashExtensions
  include ControllerExtensions
  include CheckForUnsafeHtml

  # temporarily silence deprecation warnings
  # ActiveSupport::Deprecation.silenced = true

  def get(*args, &block)
    super(*args, &block)
    check_for_unsafe_html!
  end

  def post(*args, &block)
    args = extract_body(check_for_params(args))
    super(*args, &block)
    check_for_unsafe_html!
  end

  def put(*args, &block)
    super(*args, &block)
    check_for_unsafe_html!
  end

  def delete(*args, &block)
    args = check_for_params(args)
    super(*args, &block)
    check_for_unsafe_html!
  end

  def check_for_params(args)
    return args if (args.length < 2) || args[1][:params]

    [args[0], { params: args[1] }] + args[2..]
  end

  def extract_body(args)
    if args.length >= 2
      params = args[1][:params]
      args[1][:body] = params.delete(:body).read if params.member?(:body)
    end
    args
  end
end
```

Remove Rails 5.2 `delete` monkey-patch
user
```ruby
# frozen_string_literal: true

#
#  = Functional Test Case
#
#  The test case class that all functional tests currently derive from.
#  Includes:
#
#  1. Some general-purpose helpers and assertions from GeneralExtensions.
#  2. Some controller-related helpers and assertions from ControllerExtensions.
#  3. A few helpers that encapsulate testing the flash error mechanism.
#
################################################################################

class FunctionalTestCase < ActionController::TestCase
  include GeneralExtensions
  include FlashExtensions
  include ControllerExtensions
  include CheckForUnsafeHtml

  # temporarily silence deprecation warnings
  # ActiveSupport::Deprecation.silenced = true

  def get(*args, &block)
    super(*args, &block)
    check_for_unsafe_html!
  end

  def post(*args, &block)
    args = extract_body(check_for_params(args))
    super(*args, &block)
    check_for_unsafe_html!
  end

  def put(*args, &block)
    super(*args, &block)
    check_for_unsafe_html!
  end

  def delete(*args, &block)
    super(*args, &block)
    check_for_unsafe_html!
  end

  def check_for_params(args)
    return args if (args.length < 2) || args[1][:params]

    [args[0], { params: args[1] }] + args[2..]
  end

  def extract_body(args)
    if args.length >= 2
      params = args[1][:params]
      args[1][:body] = params.delete(:body).read if params.member?(:body)
    end
    args
  end
end
```
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