FIX: `TopicTagsChanged` trigger not working with multiple tags (#29961)

* FIX: `TopicTagsChanged` trigger not working with multiple tags

The check for when had multiple tags was being exclusive, you had to have all tags to trigger the automation, now it's inclusive, you can trigger the automation if you have any of the tags.

* DEV: add specs for when having multiple categories

* DEV: changed to use unions and intersections for tags

added more tests to check for multiple tags

plugins/automation/lib/discourse_automation/event_handlers.rb

@@ -239,12 +239,8 @@ module DiscourseAutomation
           watching_tags = automation.trigger_field("watching_tags")
 
           if watching_tags["value"]
-            should_skip = false
-            watching_tags["value"].each do |tag|
-              should_skip = true if !removed_tags.empty? && !removed_tags.include?(tag)
-              should_skip = true if !added_tags.empty? && !added_tags.include?(tag)
-            end
-            next if should_skip
+            changed_tags = (removed_tags | added_tags)
+            next if (changed_tags & watching_tags["value"]).empty?
           end
 
           automation.trigger!(

plugins/automation/spec/triggers/topic_tags_changed_spec.rb

@@ -82,6 +82,66 @@ describe DiscourseAutomation::Triggers::TOPIC_TAGS_CHANGED do
     end
   end
 
+  context "when watching a few cool tags" do
+    fab!(:cool_tag_2) { Fabricate(:tag) }
+    fab!(:cool_tag_3) { Fabricate(:tag) }
+
+    before do
+      automation.upsert_field!(
+        "watching_tags",
+        "tags",
+        { value: [cool_tag.name, cool_tag_2.name, cool_tag_3.name] },
+        target: "trigger",
+      )
+      automation.reload
+    end
+
+    it "should fire the trigger if any tag is added" do
+      topic_0 = Fabricate(:topic, user: user, tags: [], category: category)
+
+      list =
+        capture_contexts do
+          DiscourseTagging.tag_topic_by_names(topic_0, Guardian.new(user), [cool_tag.name])
+        end
+
+      expect(list.length).to eq(1)
+      expect(list[0]["kind"]).to eq(DiscourseAutomation::Triggers::TOPIC_TAGS_CHANGED)
+    end
+
+    it "should fire the trigger if any tag is removed" do
+      topic_0 = Fabricate(:topic, user: user, tags: [cool_tag], category: category)
+
+      list =
+        capture_contexts { DiscourseTagging.tag_topic_by_names(topic_0, Guardian.new(user), []) }
+
+      expect(list.length).to eq(1)
+      expect(list[0]["kind"]).to eq(DiscourseAutomation::Triggers::TOPIC_TAGS_CHANGED)
+    end
+
+    it "should not fire if the tag is not present" do
+      topic_0 = Fabricate(:topic, user: user, tags: [], category: category)
+
+      list =
+        capture_contexts do
+          DiscourseTagging.tag_topic_by_names(topic_0, Guardian.new(user), [bad_tag.name])
+        end
+
+      expect(list.length).to eq(0)
+    end
+
+    it "should fire the trigger if a tag is add and one is removed" do
+      topic_0 = Fabricate(:topic, user: user, tags: [cool_tag], category: category)
+
+      list =
+        capture_contexts do
+          DiscourseTagging.tag_topic_by_names(topic_0, Guardian.new(user), [cool_tag_2.name])
+        end
+
+      expect(list.length).to eq(1)
+      expect(list[0]["kind"]).to eq(DiscourseAutomation::Triggers::TOPIC_TAGS_CHANGED)
+    end
+  end
+
   context "when watching a category" do
     before do
       automation.upsert_field!(
@@ -128,6 +188,55 @@ describe DiscourseAutomation::Triggers::TOPIC_TAGS_CHANGED do
     end
   end
 
+  context "when watching a few categories" do
+    fab!(:category_2) { Fabricate(:category) }
+    fab!(:category_3) { Fabricate(:category) }
+
+    before do
+      automation.upsert_field!(
+        "watching_categories",
+        "categories",
+        { value: [category.id, category_2.id, category_3.id] },
+        target: "trigger",
+      )
+      automation.reload
+    end
+
+    it "should fire the trigger if any tag is added" do
+      topic_0 = Fabricate(:topic, user: user, tags: [], category: category)
+      topic_1 = Fabricate(:topic, user: user, tags: [], category: category_2)
+
+      list =
+        capture_contexts do
+          DiscourseTagging.tag_topic_by_names(topic_0, Guardian.new(user), [bad_tag.name])
+          DiscourseTagging.tag_topic_by_names(topic_1, Guardian.new(user), [bad_tag.name])
+        end
+
+      expect(list.length).to eq(2)
+      expect(list[0]["kind"]).to eq(DiscourseAutomation::Triggers::TOPIC_TAGS_CHANGED)
+    end
+
+    it "should fire the trigger if any tag is removed" do
+      topic_0 = Fabricate(:topic, user: user, tags: [cool_tag], category: category)
+
+      list =
+        capture_contexts { DiscourseTagging.tag_topic_by_names(topic_0, Guardian.new(user), []) }
+      expect(list.length).to eq(1)
+      expect(list[0]["kind"]).to eq(DiscourseAutomation::Triggers::TOPIC_TAGS_CHANGED)
+    end
+
+    it "should not fire if not the watching category" do
+      topic_0 = Fabricate(:topic, user: user, tags: [], category: Fabricate(:category))
+
+      list =
+        capture_contexts do
+          DiscourseTagging.tag_topic_by_names(topic_0, Guardian.new(user), [cool_tag.name])
+        end
+
+      expect(list.length).to eq(0)
+    end
+  end
+
   context "when without any watching tags or categories" do
     it "should fire the trigger if the tag is added" do
       topic_0 = Fabricate(:topic, user: user, tags: [], category: category)