fix: built-in pages could be turned into tags

Fixes https://github.com/logseq/db-test/issues/333.
Also added guards at handler level in case they are used elsewhere.
Made sure to couple them to outliner-validate as centralizing validation
is important if we want to have a consistent, bug-free approach
to updating entities

deps/outliner/src/logseq/outliner/validate.cljs

@@ -37,10 +37,12 @@
                             :payload {:message "Page name can't be blank."
                                       :type :warning}})))))
 
+(def uneditable-page? ldb/built-in?)
+
 (defn ^:api validate-built-in-pages
   "Validates built-in pages shouldn't be modified"
   [entity]
-  (when (ldb/built-in? entity)
+  (when (uneditable-page? entity)
     (throw (ex-info "Rename built-in pages"
                     {:type :notification
                      :payload {:message "Built-in pages can't be edited"

src/main/frontend/components/page_menu.cljs

@@ -148,7 +148,7 @@
                :options {:on-click #(commands/exec-plugin-simple-command!
                                      pid (assoc cmd :page page-name) action)}}))
 
-          (when (and db-based? (ldb/internal-page? page))
+          (when (and db-based? (ldb/internal-page? page) (not (:logseq.property/built-in? page)))
             {:title (t :page/convert-to-tag)
              :options {:on-click (fn []
                                    (db-page-handler/convert-page-to-tag! page))}})

src/main/frontend/handler/db_based/page.cljs

@@ -49,6 +49,8 @@
         (notification/show! (str "A tag with the name \"" (:block/title page-entity) "\" already exists.") :warning false)
         (:block/parent page-entity)
         (notification/show! "Namespaced pages can't be tags" :error false)
+        (outliner-validate/uneditable-page? page-entity)
+        (notification/show! "Built-in pages can't be edited" :error)
         :else
         (let [txs [(db-class/build-new-class (db/get-db)
                                              {:db/id (:db/id page-entity)
@@ -60,32 +62,34 @@
 
 (defn convert-tag-to-page!
   [entity]
-  (if (db/page-exists? (:block/title entity) #{:logseq.class/Page})
-    (notification/show! (str "A page with the name \"" (:block/title entity) "\" already exists.") :warning false)
-    (when-not (:logseq.property/built-in? entity)
-      (if (seq (:logseq.property.class/_extends entity))
-        (notification/show! "This tag cannot be converted because it has tag children. All tag children must be removed or converted before converting this tag." :error false)
-        (p/let [objects (db-async/<get-tag-objects (state/get-current-repo) (:db/id entity))]
-          (let [convert-fn
-                (fn convert-fn []
-                  (let [page-txs [[:db/retract (:db/id entity) :db/ident]
-                                  [:db/retract (:db/id entity) :block/tags :logseq.class/Tag]
-                                  [:db/retract (:db/id entity) :logseq.property.class/extends]
-                                  [:db/retract (:db/id entity) :logseq.property.class/properties]
-                                  [:db/add (:db/id entity) :block/tags :logseq.class/Page]]
-                        obj-txs (mapcat (fn [obj]
-                                          (let [tags (map #(db/entity (state/get-current-repo) (:db/id %)) (:block/tags obj))]
-                                            [{:db/id (:db/id obj)
-                                              :block/title (db-content/replace-tag-refs-with-page-refs (:block/title obj) tags)}
-                                             [:db/retract (:db/id obj) :block/tags (:db/id entity)]]))
-                                        objects)
-                        txs (concat page-txs obj-txs)]
-                    (db/transact! (state/get-current-repo) txs {:outliner-op :save-block})))]
-            (-> (shui/dialog-confirm!
-                 "Converting a tag to page also removes its tag properties and its tag from all nodes tagged with it. Are you ok with that?"
-                 {:id :convert-tag-to-page
-                  :data-reminder :ok})
-                (p/then convert-fn))))))))
+  (cond (db/page-exists? (:block/title entity) #{:logseq.class/Page})
+        (notification/show! (str "A page with the name \"" (:block/title entity) "\" already exists.") :warning false)
+        (outliner-validate/uneditable-page? entity)
+        (notification/show! "Built-in tags can't be edited" :error)
+        :else
+        (if (seq (:logseq.property.class/_extends entity))
+          (notification/show! "This tag cannot be converted because it has tag children. All tag children must be removed or converted before converting this tag." :error false)
+          (p/let [objects (db-async/<get-tag-objects (state/get-current-repo) (:db/id entity))]
+            (let [convert-fn
+                  (fn convert-fn []
+                    (let [page-txs [[:db/retract (:db/id entity) :db/ident]
+                                    [:db/retract (:db/id entity) :block/tags :logseq.class/Tag]
+                                    [:db/retract (:db/id entity) :logseq.property.class/extends]
+                                    [:db/retract (:db/id entity) :logseq.property.class/properties]
+                                    [:db/add (:db/id entity) :block/tags :logseq.class/Page]]
+                          obj-txs (mapcat (fn [obj]
+                                            (let [tags (map #(db/entity (state/get-current-repo) (:db/id %)) (:block/tags obj))]
+                                              [{:db/id (:db/id obj)
+                                                :block/title (db-content/replace-tag-refs-with-page-refs (:block/title obj) tags)}
+                                               [:db/retract (:db/id obj) :block/tags (:db/id entity)]]))
+                                          objects)
+                          txs (concat page-txs obj-txs)]
+                      (db/transact! (state/get-current-repo) txs {:outliner-op :save-block})))]
+              (-> (shui/dialog-confirm!
+                   "Converting a tag to page also removes its tag properties and its tag from all nodes tagged with it. Are you ok with that?"
+                   {:id :convert-tag-to-page
+                    :data-reminder :ok})
+                  (p/then convert-fn)))))))
 
 (defn <create-class!
   "Creates a class page and provides class-specific error handling"