[10.x] Fix runPaginationCountQuery not working properly for union queries (#52314)

* Fix runPaginationCountQuery not working properly for union queries

* Added tests

Author: chinleung

src/Illuminate/Database/Query/Builder.php

@@ -3016,10 +3016,10 @@ protected function runPaginationCountQuery($columns = ['*'])
                 ->get()->all();
         }
 
-        $without = $this->unions ? ['orders', 'limit', 'offset'] : ['columns', 'orders', 'limit', 'offset'];
+        $without = $this->unions ? ['unionOrders', 'unionLimit', 'unionOffset'] : ['columns', 'orders', 'limit', 'offset'];
 
         return $this->cloneWithout($without)
-                    ->cloneWithoutBindings($this->unions ? ['order'] : ['select', 'order'])
+                    ->cloneWithoutBindings($this->unions ? ['unionOrder'] : ['select', 'order'])
                     ->setAggregate('count', $this->withoutSelectAliases($columns))
                     ->get()->all();
     }

tests/Database/DatabaseQueryBuilderTest.php

@@ -2070,6 +2070,34 @@ public function testGetCountForPaginationWithUnion()
         $this->assertEquals(1, $count);
     }
 
+    public function testGetCountForPaginationWithUnionOrders()
+    {
+        $builder = $this->getBuilder();
+        $builder->from('posts')->select('id')->union($this->getBuilder()->from('videos')->select('id'))->latest();
+
+        $builder->getConnection()->shouldReceive('select')->once()->with('select count(*) as aggregate from ((select "id" from "posts") union (select "id" from "videos")) as "temp_table"', [], true)->andReturn([['aggregate' => 1]]);
+        $builder->getProcessor()->shouldReceive('processSelect')->once()->andReturnUsing(function ($builder, $results) {
+            return $results;
+        });
+
+        $count = $builder->getCountForPagination();
+        $this->assertEquals(1, $count);
+    }
+
+    public function testGetCountForPaginationWithUnionLimitAndOffset()
+    {
+        $builder = $this->getBuilder();
+        $builder->from('posts')->select('id')->union($this->getBuilder()->from('videos')->select('id'))->take(15)->skip(1);
+
+        $builder->getConnection()->shouldReceive('select')->once()->with('select count(*) as aggregate from ((select "id" from "posts") union (select "id" from "videos")) as "temp_table"', [], true)->andReturn([['aggregate' => 1]]);
+        $builder->getProcessor()->shouldReceive('processSelect')->once()->andReturnUsing(function ($builder, $results) {
+            return $results;
+        });
+
+        $count = $builder->getCountForPagination();
+        $this->assertEquals(1, $count);
+    }
+
     public function testWhereShortcut()
     {
         $builder = $this->getBuilder();