修复(#75): 适配促销数量与永久订阅判定

Co-authored-by: multica-agent <github@multica.ai>

internal/logic/public/subscribe/promo_test.go

@@ -1,10 +1,13 @@
 package subscribe
 
 import (
+	"strings"
 	"testing"
 	"time"
 
 	"github.com/perfect-panel/server/internal/model/user"
+	"gorm.io/driver/mysql"
+	"gorm.io/gorm"
 )
 
 func TestPromoEligibilityEvaluatorMatch(t *testing.T) {
@@ -73,3 +76,34 @@ func TestSubscribePromoCandidateActiveWindow(t *testing.T) {
 		t.Fatal("candidate after end time should not be active")
 	}
 }
+
+func TestLastSubscribeExpireAtPrioritizesPermanentSubscription(t *testing.T) {
+	db, err := gorm.Open(mysql.New(mysql.Config{
+		DSN:                       "gorm:gorm@tcp(localhost:9910)/gorm?charset=utf8&parseTime=True&loc=Local",
+		SkipInitializeWithVersion: true,
+	}), &gorm.Config{DryRun: true, DisableAutomaticPing: true})
+	if err != nil {
+		t.Fatalf("open dry-run db: %v", err)
+	}
+
+	evaluator := &promoEligibilityEvaluator{
+		db:       db,
+		userInfo: &user.User{Id: 7},
+	}
+	var item user.Subscribe
+	tx := evaluator.lastSubscribeExpireQuery().Limit(1).Take(&item)
+
+	sql := tx.Statement.SQL.String()
+	if !strings.Contains(sql, "CASE WHEN expire_time = ? THEN 0 ELSE 1 END") {
+		t.Fatalf("SQL missing permanent subscription priority order: %s", sql)
+	}
+	if strings.Contains(sql, "expire_time !=") {
+		t.Fatalf("SQL should not filter out permanent subscriptions: %s", sql)
+	}
+	if len(tx.Statement.Vars) < 2 {
+		t.Fatalf("SQL vars length = %d, want at least 2; vars=%v", len(tx.Statement.Vars), tx.Statement.Vars)
+	}
+	if got, want := tx.Statement.Vars[1], time.UnixMilli(0); got != want {
+		t.Fatalf("permanent subscription order var = %v, want %v; vars=%v", got, want, tx.Statement.Vars)
+	}
+}