Prepare test for user deletion bug

app/Http/Controllers/UsersController.php

@@ -2,12 +2,12 @@
 
 namespace App\Http\Controllers;
 
-use DB;
-use Storage;
-use App\User;
 use App\Couple;
-use Illuminate\Http\Request;
 use App\Http\Requests\Users\UpdateRequest;
+use App\User;
+use DB;
+use Illuminate\Http\Request;
+use Storage;
 
 class UsersController extends Controller
 {
@@ -216,11 +216,24 @@ class UsersController extends Controller
     private function replaceUserOnCouplesTable($oldUserId, $replacementUserId)
     {
         foreach (['husband_id', 'wife_id', 'manager_id'] as $field) {
+            if (in_array($field, ['husband_id', 'wife_id'])) {
+                $replacementUserCouples = Couple::where('husband_id', $replacementUserId)
+                    ->orWhere('wive_id', $replacementUserId)
+                    ->get();
+                if ($replacementUserCouples->isEmpty()) {
+                    DB::table('couples')->where($field, $oldUserId)->update([
+                        $field => $replacementUserId,
+                    ]);
+                } else {
+                    $replacementUserCouples->first()->delete();
+                }
+            } else {
                 DB::table('couples')->where($field, $oldUserId)->update([
                     $field => $replacementUserId,
                 ]);
             }
         }
+    }
 
     /**
      * Get User list based on gender.

tests/Feature/UsersDeletionTest.php

@@ -2,10 +2,10 @@
 
 namespace Tests\Feature;
 
-use App\User;
 use App\Couple;
-use Tests\TestCase;
+use App\User;
 use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
 
 class UsersDeletionTest extends TestCase
 {
@@ -253,4 +253,44 @@ class UsersDeletionTest extends TestCase
         $this->seeElement('option', ['value' => $replacementMaleUser->id]);
         $this->dontSeeElement('option', ['value' => $femaleUser->id]);
     }
+
+    /** @test */
+    public function bugfix_handle_duplicated_couple_on_user_deletion()
+    {
+        $manager = $this->loginAsUser();
+        $oldUser = factory(User::class)->states('male')->create([
+            'manager_id' => $manager->id,
+        ]);
+        $replacementUser = factory(User::class)->states('male')->create([
+            'manager_id' => $manager->id,
+        ]);
+        $oldUserCouple = factory(Couple::class)->create([
+            'husband_id' => $oldUser->id,
+            'wife_id'    => '999999',
+        ]);
+        $duplicatedCouple = factory(Couple::class)->create([
+            'husband_id' => $replacementUser->id,
+            'wife_id'    => '999999',
+        ]);
+
+        $this->visit(route('users.edit', [$oldUser, 'action' => 'delete']));
+        $this->see(__('user.replace_delete_text'));
+
+        $this->submitForm(__('user.replace_delete_button'), [
+            'replacement_user_id' => $replacementUser->id,
+        ]);
+
+        $this->dontSeeInDatabase('users', [
+            'id' => $oldUser->id,
+        ]);
+
+        $this->dontSeeInDatabase('couples', [
+            'husband_id' => $oldUser->id,
+        ]);
+
+        $this->seeInDatabase('couples', [
+            'id'         => $oldUserCouple->id,
+            'husband_id' => $replacementUser->id,
+        ]);
+    }
 }