POC for laravel/framework#31778 bulletproofing incrementOrDecrement and backport laravel pull/47450

Author: Pantea Marius-ciclistu

illuminate/Database/Eloquent/Model.php

@@ -984,8 +984,12 @@ protected function incrementOrDecrement($column, $amount, $extra, $method)
 
         $this->forceFill($extra);
 
-        if ($this->fireModelEvent('updating') === false) {
-            return false;
+        if (!$this->isDirty() || $this->fireModelEvent('updating') === false) {
+            return 0;
+        }
+
+        if ($this->isClassDeviable($column)) {
+            $amount = (clone $this)->setAttribute($column, $amount)->getAttributeFromArray($column);
         }
 
         return tap(
@@ -1271,18 +1275,18 @@ protected function performUpdate(Builder $query)
         // Once we have run the update operation, we will fire the "updated" event for
         // this model instance. This will allow developers to hook into these after
         // models are updated, giving them a chance to do any special processing.
-        $dirty = $this->getDirtyForUpdate();
+        if ([] === $dirty = $this->getDirtyForUpdate()) {
+            return false;
+        }
 
-        if ([] !== $dirty) {
-            $this->setKeysForSaveQuery($query)->update($dirty);
+        $this->setKeysForSaveQuery($query)->update($dirty);
 
-            $this->syncChanges();
+        $this->syncChanges();
 
-            $this->tmpDirtyIfAttributesAreSyncedFromCashedCasts = null;
-            $this->tmpOriginalBeforeAfterEvents = $this->attributes;
+        $this->tmpDirtyIfAttributesAreSyncedFromCashedCasts = null;
+        $this->tmpOriginalBeforeAfterEvents = $this->attributes;
 
-            $this->fireModelEvent('updated', false);
-        }
+        $this->fireModelEvent('updated', false);
 
         return true;
     }