fix undeleting notes with a relation, closes #3583

src/becca/entities/abstract_entity.js

@@ -80,14 +80,14 @@ class AbstractEntity {
      *
      * @returns {this}
      */
-    save() {
+    save(opts = {}) {
         const entityName = this.constructor.entityName;
         const primaryKeyName = this.constructor.primaryKeyName;
 
         const isNewEntity = !this[primaryKeyName];
 
         if (this.beforeSaving) {
-            this.beforeSaving();
+            this.beforeSaving(opts);
         }
 
         const pojo = this.getPojoToSave();

src/becca/entities/attribute.js

@@ -176,8 +176,10 @@ class Attribute extends AbstractEntity {
         return !(this.attributeId in this.becca.attributes);
     }
 
-    beforeSaving() {
-        this.validate();
+    beforeSaving(opts = {}) {
+        if (!opts.skipValidation) {
+            this.validate();
+        }
 
         this.name = sanitizeAttributeName(this.name);
 

src/services/notes.js

@@ -661,7 +661,8 @@ function undeleteBranch(branchId, deleteId, taskContext) {
                            OR (type = 'relation' AND value = ?))`, [deleteId, note.noteId, note.noteId]);
 
         for (const attribute of attributes) {
-            new Attribute(attribute).save();
+            // relation might point to a note which hasn't been undeleted yet and would thus throw up
+            new Attribute(attribute).save({skipValidation: true});
         }
 
         const childBranchIds = sql.getColumn(`