Allow blank categories for non-default feeds

app/models/feed.rb

@@ -242,13 +242,14 @@ def itunes_category
   end
 
   def itunes_category=(value)
-    if (cat = itunes_categories[0])
-      if cat.name != value
-        cat.name = value
-        cat.subcategories = []
-      end
-    else
-      itunes_categories.build(name: value)
+    cat = itunes_categories[0] || itunes_categories.build
+
+    # allow destroying for non-default feeds
+    if custom? && value.blank?
+      cat.mark_for_destruction
+    elsif cat.name != value
+      cat.name = value
+      cat.subcategories = []
     end
   end
 

test/models/feed_test.rb

@@ -285,4 +285,28 @@
       refute feed1.publish_to_apple?(create(:apple_config, public_feed: create(:feed), private_feed: create(:feed)))
     end
   end
+
+  describe "#itunes_category" do
+    it "is required for default feeds" do
+      assert_equal 1, feed1.itunes_categories.count
+      assert_equal "Leisure", feed1.itunes_category
+      assert_equal "Aviation", feed1.itunes_subcategory
+
+      feed1.itunes_category = nil
+      assert feed1.invalid?
+      assert_match(/can't be blank/i, feed1.errors.full_messages_for("itunes_categories.name").join)
+    end
+
+    it "can be deleted for non-default feeds" do
+      create(:itunes_category, feed: feed2)
+
+      assert_equal 1, feed2.itunes_categories.count
+      assert_equal "Leisure", feed2.itunes_category
+      assert_equal "Aviation", feed2.itunes_subcategory
+
+      feed2.itunes_category = nil
+      assert feed2.valid?
+      assert feed2.itunes_categories[0].marked_for_destruction?
+    end
+  end
 end