订阅列表：订阅号链接用 Arr::query 统一 back 且避免嵌套

resources/views/admin/site_subscriptions/index.blade.php

@@ -164,7 +164,12 @@
             <tr>
                 <td>{{ $subscription->id }}</td>
                 <td>
-                    <a href="/admin/site-subscriptions/{{ $subscription->id }}?back={{ urlencode($back) }}">{{ $subscription->subscription_no }}</a>
+                    @php
+                        $subShowUrl = '/admin/site-subscriptions/' . $subscription->id . '?' . \Illuminate\Support\Arr::query([
+                            'back' => $back,
+                        ]);
+                    @endphp
+                    <a href="{!! $subShowUrl !!}">{{ $subscription->subscription_no }}</a>
                 </td>
                 <td>
                     @if($subscription->merchant)

tests/Feature/AdminSiteSubscriptionIndexSubscriptionNoLinkContainsBackTest.php

@@ -0,0 +1,72 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Models\Merchant;
+use App\Models\Plan;
+use App\Models\SiteSubscription;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Arr;
+use Tests\TestCase;
+
+class AdminSiteSubscriptionIndexSubscriptionNoLinkContainsBackTest 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_subscription_no_link_should_carry_back_to_index_self_without_back(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $merchant = Merchant::query()->firstOrFail();
+        $plan = Plan::query()->create([
+            'code' => 'sub_index_sub_no_back_plan',
+            'name' => '订阅列表订阅号 back 口径测试套餐',
+            'billing_cycle' => 'monthly',
+            'price' => 10,
+            'list_price' => 10,
+            'status' => 'active',
+            'sort' => 10,
+            'published_at' => now(),
+        ]);
+
+        $sub = SiteSubscription::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $plan->id,
+            'status' => 'activated',
+            'source' => 'manual',
+            'subscription_no' => 'SUB_INDEX_BACK_0001',
+            'plan_name' => $plan->name,
+            'billing_cycle' => $plan->billing_cycle,
+            'period_months' => 1,
+            'amount' => 10,
+            'starts_at' => now()->subDay(),
+            'ends_at' => now()->addMonth(),
+            'activated_at' => now()->subDay(),
+        ]);
+
+        // 列表页带 back（模拟从其它页面跳回），index 内 back 口径用 selfWithoutBack（去掉 back）
+        $res = $this->get('/admin/site-subscriptions?status=activated&back=' . urlencode('/admin/plans'));
+        $res->assertOk();
+
+        $expectedBack = '/admin/site-subscriptions?' . Arr::query([
+            'status' => 'activated',
+        ]);
+
+        $expectedUrl = '/admin/site-subscriptions/' . $sub->id . '?' . Arr::query([
+            'back' => $expectedBack,
+        ]);
+
+        $res->assertSee($expectedUrl, false);
+        $res->assertDontSee('back%3D', false);
+    }
+}