```ruby
require 'rubygems'

# All our specs should require 'spec_helper' (this file)

# If RACK_ENV isn't set, set it to 'test'.  Sinatra defaults to development,
# so we have to override that unless we want to set RACK_ENV=test from the
# command line when we run rake spec.  That's tedious, so do it here.
ENV['RACK_ENV'] ||= 'test'

require File.expand_path("../../config/environment", __FILE__)
require 'shoulda-matchers'
require 'rack/test'
require 'capybara'
require 'capybara/rspec'

RSpec.configure do |config|
  config.include Rack::Test::Methods
  config.include(Shoulda::Matchers::ActiveRecord, type: :model)
end

def app
  Sinatra::Application
end

def new_bands_path
  '/bands/new'
end
```

Update spec helper to include ActiveModel
user
```ruby
require 'rubygems'

# All our specs should require 'spec_helper' (this file)

# If RACK_ENV isn't set, set it to 'test'.  Sinatra defaults to development,
# so we have to override that unless we want to set RACK_ENV=test from the
# command line when we run rake spec.  That's tedious, so do it here.
ENV['RACK_ENV'] ||= 'test'

require File.expand_path("../../config/environment", __FILE__)
require 'shoulda-matchers'
require 'rack/test'
require 'capybara'
require 'capybara/rspec'

RSpec.configure do |config|
  config.include Rack::Test::Methods
  config.include(Shoulda::Matchers::ActiveRecord, type: :model)
  config.include(Shoulda::Matchers::ActiveModel, type: :model)
end

def app
  Sinatra::Application
end

def new_bands_path
  '/bands/new'
end
```
assistant