Fix extra i18n namespacing (#293)

* Add a test that looks at i18n working in Modules included
* Demonstrates #290
* Correct name collision with I18n with UseI18n
(fixes #290)

lib/pagy/extras/i18n.rb

@@ -10,10 +10,10 @@ module Frontend
 
     Pagy::I18n.clear.instance_eval { undef :load; undef :t } # unload the pagy default constant for efficiency
 
-    module I18n
+    module UseI18nGem
       def pagy_t(key, **opts) = ::I18n.t(key, **opts)
     end
-    prepend I18n
+    prepend UseI18nGem
 
   end
 end

test/mock_helpers/application_helper.rb

@@ -0,0 +1,8 @@
+module ApplicationHelper
+  include Pagy::Frontend
+
+  def any_method_name()
+    I18n.t("test")
+  end
+
+end

test/pagy/extras/i18n_test.rb

@@ -7,11 +7,17 @@
 
 SimpleCov.command_name 'i18n' if ENV['RUN_SIMPLECOV'] == 'true'
 
+require_relative '../../mock_helpers/application_helper'
+include ApplicationHelper
+
 describe Pagy::Frontend do
 
   let(:view) { MockView.new }
 
   describe "#pagy_t with I18n" do
+    it 'works with an included Module' do
+      ApplicationHelper.any_method_name()
+    end
 
     it 'pluralizes' do
       _(view.pagy_t('pagy.nav.prev')).must_equal "‹ Prev"