Encapsulate tagging as a taggable domain method

Tag scope control should not float around in the controller

test/controllers/tags_controller_test.rb

@@ -0,0 +1,25 @@
+require "test_helper"
+
+class TagsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    sign_in_as :kevin
+  end
+
+  test "create with existing tag" do
+    assert_no_difference -> { accounts(:"37s").tags.count } do
+      post bucket_bubble_tags_url(buckets(:writebook), bubbles(:logo)), params: { tag: { title: "Web" } }
+    end
+
+    assert_redirected_to bubbles(:logo)
+  end
+
+  test "create with new tag" do
+    assert_difference -> { accounts(:"37s").tags.count }, +1 do
+      post bucket_bubble_tags_url(buckets(:writebook), bubbles(:logo)), params: { tag: { title: "Horizons" } }
+    end
+
+    assert_redirected_to bubbles(:logo)
+    assert bubbles(:logo).tags.pluck(:title).include?("Horizons")
+  end
+end
+