test: plans index edit link contains back without nesting

tests/Feature/AdminPlanIndexEditLinkContainsBackToSelfWithoutBackTest.php

@@ -0,0 +1,63 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Models\Plan;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Arr;
+use Tests\TestCase;
+
+class AdminPlanIndexEditLinkContainsBackToSelfWithoutBackTest extends TestCase
+{
+    use RefreshDatabase;
+
+    protected function loginAsPlatformAdmin(): void
+    {
+        $this->seed();
+
+        $this->post('/admin/login', [
+            'email' => 'platform.admin@demo.local',
+            'password' => 'Platform@123456',
+        ])->assertRedirect('/admin');
+    }
+
+    public function test_edit_link_should_carry_back_to_index_self_without_back_and_should_not_nest_back(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $plan = Plan::query()->create([
+            'code' => 'plan_edit_link_back_test',
+            'name' => '套餐编辑链接 back 测试',
+            'billing_cycle' => 'monthly',
+            'price' => 99,
+            'list_price' => 99,
+            'status' => 'active',
+            'sort' => 1,
+            'published_at' => now(),
+        ]);
+
+        // 模拟：套餐列表页本身带 back（例如从别的模块跳转过来），避免 edit 链接把 back 再嵌套进去
+        $currentUrl = '/admin/plans?' . Arr::query([
+            'status' => 'active',
+            'billing_cycle' => 'monthly',
+            'back' => '/admin',
+        ]);
+
+        $res = $this->get($currentUrl);
+        $res->assertOk();
+
+        $selfWithoutBack = '/admin/plans?' . Arr::query([
+            'status' => 'active',
+            'billing_cycle' => 'monthly',
+        ]);
+
+        $expectedEditUrl = '/admin/plans/' . $plan->id . '/edit?' . Arr::query([
+            'back' => $selfWithoutBack,
+        ]);
+
+        $res->assertSee($expectedEditUrl, false);
+
+        // 防 back 嵌套：不应出现 back=...back=... 的编码片段
+        $res->assertDontSee('back%3D', false);
+    }
+}