Investigating a strange issue with named routes and namespaced controllers

namespaced_controller_routes.rb

begin
  require 'bundler/inline'
  require 'pry'
rescue LoadError => e
  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
  raise e
end

gemfile(true) do
  source 'https://rubygems.org'

  gem 'rails', '5.2.1'
end

require 'rack/test'
require 'active_storage/engine'
require 'action_controller/railtie'

class TestApp < Rails::Application
  config.root = File.dirname(__FILE__)
  config.session_store :cookie_store, key: 'cookie_store_key'
  secrets.secret_token    = 'secret_token'
  secrets.secret_key_base = 'secret_key_base'

  config.eager_load = false
  config.logger = Logger.new($stdout)
  Rails.logger  = config.logger
end

Rails.application.initialize!

TestApp.routes.draw do
  get '/blob' => 'active_storage/blobs#show'
  get '/test' => 'test#show'
  get '/login' => 'sessions#new', as: :login
end

class ApplicationController < ActionController::Base
  before_action :redirect_to_login

  private

  def redirect_to_login
    if params[:inner_options]
      redirect_to login_path({})
    else
      redirect_to login_path
    end
  end
end

class ActiveStorage::BaseController < ApplicationController
  protect_from_forgery with: :exception

  before_action do
    ActiveStorage::Current.host = request.base_url
  end
end

class SessionsController < ApplicationController
  def new
    render text: 'login'
  end
end

class TestController < ApplicationController
  def show
    render text: 'test'
  end
end

class ActiveStorage::BlobsController < ActiveStorage::BaseController
  def show
    render text: 'blob'
  end
end

require 'minitest/autorun'

class TestControllerTest < ActionDispatch::IntegrationTest
  test "should redirect to the login page" do
    get '/test'
    assert_equal 302, response.status
    assert_equal "http://www.example.com/login", response.headers["location"]
  end

  test "should redirect to the login page with inner_options" do
    get '/test?inner_options=1'
    assert_equal 302, response.status
    assert_equal "http://www.example.com/login", response.headers["location"]
  end
end

class ActiveStorage::BlobsControllerTest < ActionDispatch::IntegrationTest
  test "should redirect to the login page" do
    get '/blob'
    assert_equal 302, response.status
    assert_equal "http://www.example.com/login", response.headers["location"]
  end

  test "should redirect to the login page with inner_options" do
    get '/blob?inner_options=1'
    assert_equal 302, response.status
    assert_equal "http://www.example.com/login", response.headers["location"]
  end
end