Avoid calling query() twice by adding a local var, fixes #4133 and #4140

src/Sheet.php

@@ -465,13 +465,18 @@ public function fromView(FromView $sheetExport, $sheetIndex = null)
      */
     public function fromQuery(FromQuery $sheetExport, Worksheet $worksheet)
     {
-        if ($sheetExport->query() instanceof \Laravel\Scout\Builder) {
+        $query = $sheetExport->query();
+        if ($query instanceof \Laravel\Scout\Builder) {
             $this->fromScout($sheetExport, $worksheet);
 
             return;
         }
 
-        $sheetExport->query()->chunk($this->getChunkSize($sheetExport), function ($chunk) use ($sheetExport) {
+        //Operate on a clone to avoid altering the original
+        //and use the clone operator directly to support old versions of Laravel
+        //that don't have a clone method in eloquent
+        $clonedQuery = clone $query;
+        $clonedQuery->chunk($this->getChunkSize($sheetExport), function ($chunk) use ($sheetExport) {
             $this->appendRows($chunk, $sheetExport);
         });
     }

tests/Concerns/FromQueryTest.php

@@ -11,6 +11,7 @@
 use Maatwebsite\Excel\Tests\Data\Stubs\FromUsersQueryExport;
 use Maatwebsite\Excel\Tests\Data\Stubs\FromUsersQueryExportWithEagerLoad;
 use Maatwebsite\Excel\Tests\Data\Stubs\FromUsersQueryExportWithPrepareRows;
+use Maatwebsite\Excel\Tests\Data\Stubs\FromUsersQueryWithJoinExport;
 use Maatwebsite\Excel\Tests\Data\Stubs\FromUsersScoutExport;
 use Maatwebsite\Excel\Tests\TestCase;
 
@@ -61,6 +62,23 @@ public function test_can_export_from_query()
         $this->assertEquals($allUsers, $contents);
     }
 
+    public function test_can_export_from_query_with_join()
+    {
+        $export = new FromUsersQueryWithJoinExport();
+
+        $response = $export->store('from-query-store.xlsx');
+
+        $this->assertTrue($response);
+
+        $contents = $this->readAsArray(__DIR__ . '/../Data/Disks/Local/from-query-store.xlsx', 'Xlsx');
+
+        $allUsers = $export->query->get()->map(function (User $user) {
+            return array_values($user->toArray());
+        })->toArray();
+
+        $this->assertEquals($allUsers, $contents);
+    }
+
     public function test_can_export_from_relation_query_queued()
     {
         $export = new FromGroupUsersQueuedQueryExport();

tests/Data/Stubs/FromUsersQueryWithJoinExport.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace Maatwebsite\Excel\Tests\Data\Stubs;
+
+use Illuminate\Database\Eloquent\Builder as EloquentBuilder;
+use Illuminate\Database\Eloquent\Relations\Relation;
+use Illuminate\Database\Query\Builder;
+use Maatwebsite\Excel\Concerns\Exportable;
+use Maatwebsite\Excel\Concerns\FromQuery;
+use Maatwebsite\Excel\Concerns\WithCustomChunkSize;
+use Maatwebsite\Excel\Tests\Data\Stubs\Database\User;
+
+class FromUsersQueryWithJoinExport implements FromQuery, WithCustomChunkSize
+{
+    use Exportable;
+
+    public $query;
+
+    public function __construct()
+    {
+        $this->query = User::query();
+    }
+
+    /**
+     * @return Builder|EloquentBuilder|Relation
+     */
+    public function query()
+    {
+        return $this->query
+            ->join(
+                'group_user',
+                'group_user.user_id',
+                '=',
+                'users.id'
+            )
+            ->select('users.*', 'group_user.group_id as gid');
+    }
+
+    /**
+     * @return int
+     */
+    public function chunkSize(): int
+    {
+        return 10;
+    }
+}