fix: multiple pagers with models do not work

Author: kenjis

system/BaseModel.php

@@ -1073,7 +1073,8 @@ public function errors(bool $forceDB = false)
      */
     public function paginate(?int $perPage = null, string $group = 'default', ?int $page = null, int $segment = 0)
     {
-        $pager = Services::pager(null, null, false);
+        // Since multiple models may use the Pager, the Pager must be shared.
+        $pager = Services::pager();
 
         if ($segment) {
             $pager->setSegment($segment, $group);

tests/system/Models/PaginateModelTest.php

@@ -79,4 +79,26 @@ public function testPaginatePageOutOfRange(): void
         $this->model->paginate(1, 'default', 500);
         $this->assertSame($this->model->pager->getPageCount(), $this->model->pager->getCurrentPage());
     }
+
+    public function testMultiplePager(): void
+    {
+        $validModel = $this->createModel(ValidModel::class);
+        $userModel  = $this->createModel(UserModel::class);
+
+        $validModel->paginate(1, 'valid');
+        $userModel->paginate(1, 'user');
+        $pager = $this->model->pager;
+
+        $this->assertSame(4, $validModel->countAllResults());
+        $this->assertSame(4, $userModel->countAllResults());
+
+        $this->assertStringContainsString('?page_valid=1"', $pager->links('valid'));
+        $this->assertStringContainsString('?page_valid=2"', $pager->links('valid'));
+        $this->assertStringContainsString('?page_valid=3"', $pager->links('valid'));
+        $this->assertStringContainsString('?page_valid=4"', $pager->links('valid'));
+        $this->assertStringContainsString('?page_user=1"', $pager->links('user'));
+        $this->assertStringContainsString('?page_user=2"', $pager->links('user'));
+        $this->assertStringContainsString('?page_user=3"', $pager->links('user'));
+        $this->assertStringContainsString('?page_user=4"', $pager->links('user'));
+    }
 }