Stubbing Rails Settings

stub_settings.rb

# a module included
module StubSettings
  def stub_setting(setting_name, setting_value)
    allow(Setting).to receive(:[]).with(setting_name).and_return(setting_value)
  end

  def stub_setting_assignment
    allow(Setting).to receive(:[]=) { |setting, value| stub_setting(setting, setting) }
  end
end

# in spec_helper.rb
  config.before(:each) do
    # detect if Settings being set without you knowing about it
    allow(Setting).to receive(:[]=)
      .and_raise("stub_setting(setting_name, setting_value) to set the value of a Setting instead")
    # passthrough read-only settings calls (necessary if you don't want .with to block other settings
    allow(Setting).to receive(:[]).and_call_original
  end


# in rspec example
describe 'settings will be set in code invoked from here' do
    # automatically stubs assigned value to new stub
    before { stub_setting_assignment }
end

# stubbing a setting value
describe 'setting to be forced to a value' do
  before { stub_setting('some_toggle_setting', true) }
end