added alias

Author: Alexmg86

README.md

@@ -43,7 +43,7 @@ echo $invoices[0]->items_price_avg;
 ```
 ### The following methods apply to all methods!!!
 
-You may add the "sum" for multiple relations as well as add constraints to the queries:
+You may add the sum for multiple relations as well as add constraints to the queries:
 ```php
 use Illuminate\Database\Eloquent\Builder;
 
@@ -55,6 +55,17 @@ echo $invoices[0]->items_price_sum;
 echo $invoices[0]->goods_price_sum;
 echo $invoices[0]->goods_price2_sum;
 ```
+You may also alias the relationship sum result, allowing multiple sums on the same relationship:
+```php
+use Illuminate\Database\Eloquent\Builder;
+
+$invoices = Invoice::withSum(['items:price', 'goods:price as sum_goods_price' => function (Builder $query) {
+    $query->where('price','!=',1);
+}])->get();
+
+echo $invoices[0]->items_price_sum;
+echo $invoices[0]->sum_goods_price;
+```
 If you're combining `withSum` with a `select` statement, ensure that you call `withSum` after the `select` method:
 ```php
 $invoices = Invoice::select(['id'])->withSum('items:price')->get();

src/LaravelSubQuery.php

@@ -71,6 +71,14 @@ protected function withSubQuery($relations, $type)
         $relations = is_array($relations) ? $relations : array_slice(func_get_args(), 0, 1);
 
         foreach ($this->parseForSubQueryRelations($relations) as $name => $constraints) {
+            $segments = explode(' ', $name);
+
+            unset($alias);
+
+            if (count($segments) === 3 && Str::lower($segments[1]) === 'as') {
+                [$name, $alias] = [$segments[0], $segments[2]];
+            }
+
             $nameExplode = explode(':', $name);
             $name = $nameExplode[0];
             $columns = isset($nameExplode[1]) ? explode(',', $nameExplode[1]) : [];
@@ -103,7 +111,9 @@ protected function withSubQuery($relations, $type)
                 // Finally we will add the proper result column alias to the query and run the subselect
                 // statement against the query builder. Then we will return the builder instance back
                 // to the developer for further constraint chaining that needs to take place on it.
-                $this->selectSub($query, Str::snake($name.'_'.$column.'_'.$type));
+                $column = $alias ?? Str::snake($name.'_'.$column.'_'.$type);
+
+                $this->selectSub($query, $column);
             }
         }
 

tests/LaravelSubQueryWithAvgTest.php

@@ -85,10 +85,10 @@ public function testWithSelect()
             Item::create(['invoice_id' => $invoice->id, 'price' => $i, 'price2' => $i + 1]);
         }
 
-        $results = Invoice::select(['id'])->withAvg('items:price');
+        $results = Invoice::select(['id'])->withAvg('items:price as price_avg');
 
         $this->assertEquals([
-            ['id' => 1, 'items_price_avg' => 5.5],
+            ['id' => 1, 'price_avg' => 5.5],
         ], $results->get()->toArray());
     }
 

tests/LaravelSubQueryWithMaxTest.php

@@ -85,10 +85,10 @@ public function testWithSelect()
             Item::create(['invoice_id' => $invoice->id, 'price' => $i, 'price2' => $i + 1]);
         }
 
-        $results = Invoice::select(['id'])->withMax('items:price');
+        $results = Invoice::select(['id'])->withMax('items:price as price_max');
 
         $this->assertEquals([
-            ['id' => 1, 'items_price_max' => 10],
+            ['id' => 1, 'price_max' => 10],
         ], $results->get()->toArray());
     }
 

tests/LaravelSubQueryWithMinTest.php

@@ -85,10 +85,10 @@ public function testWithSelect()
             Item::create(['invoice_id' => $invoice->id, 'price' => $i, 'price2' => $i + 1]);
         }
 
-        $results = Invoice::select(['id'])->withMin('items:price');
+        $results = Invoice::select(['id'])->withMin('items:price as price_min');
 
         $this->assertEquals([
-            ['id' => 1, 'items_price_min' => 1],
+            ['id' => 1, 'price_min' => 1],
         ], $results->get()->toArray());
     }
 

tests/LaravelSubQueryWithSumTest.php

@@ -87,10 +87,10 @@ public function testWithSelect()
             Item::create(['invoice_id' => $invoice->id, 'price' => $i, 'price2' => $i + 1]);
         }
 
-        $results = Invoice::select(['id'])->withSum('items:price');
+        $results = Invoice::select(['id'])->withSum('items:price as price_sum');
 
         $this->assertEquals([
-            ['id' => 1, 'items_price_sum' => 55],
+            ['id' => 1, 'price_sum' => 55],
         ], $results->get()->toArray());
     }