[9.x] Fix issue with aggregates (withSum, etc.) for pivot columns on …

…self-referencing many-to-many relations (#44286)

* Add failing test for current state.

* Apply potential fix.

* Potential fix?

* Use better name

Eloquent/Concerns/QueriesRelationships.php

@@ -622,9 +622,7 @@ public function withAggregate($relations, $column, $function = null)
             $relation = $this->getRelationWithoutConstraints($name);
 
             if ($function) {
-                $hashedColumn = $this->getQuery()->from === $relation->getQuery()->getQuery()->from
-                                            ? "{$relation->getRelationCountHash(false)}.$column"
-                                            : $column;
+                $hashedColumn = $this->getRelationHashedColumn($column, $relation);
 
                 $wrappedColumn = $this->getQuery()->getGrammar()->wrap(
                     $column === '*' ? $column : $relation->getRelated()->qualifyColumn($hashedColumn)
@@ -680,6 +678,24 @@ public function withAggregate($relations, $column, $function = null)
         return $this;
     }
 
+    /**
+     * Get the relation hashed column name for the given column and relation.
+     *
+     * @param  string  $column
+     * @param  \Illuminate\Database\Eloquent\Relations\Relationship  $relation
+     * @return string
+     */
+    protected function getRelationHashedColumn($column, $relation)
+    {
+        if (str_contains($column, '.')) {
+            return $column;
+        }
+
+        return $this->getQuery()->from === $relation->getQuery()->getQuery()->from
+            ? "{$relation->getRelationCountHash(false)}.$column"
+            : $column;
+    }
+
     /**
      * Add subselect queries to count the relations.
      *