fix(trash): retain metadata when permanent deletion fails

internal/vault/trash.go

@@ -1,12 +1,41 @@
 package vault
 
 import (
+	"encoding/json"
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
 	"time"
 )
 
+// 调用方持有写锁并已读取验证元数据。先删除内容，失败时保留条目的管理依据。
+func (v *Vault) purgeTrashItemLocked(metadata trashMetadata) error {
+	dir := filepath.Join(v.trash, metadata.ID)
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return err
+	}
+	for _, entry := range entries {
+		if entry.Name() == "meta.json" {
+			continue
+		}
+		if err := os.RemoveAll(filepath.Join(dir, entry.Name())); err != nil {
+			return err
+		}
+	}
+	metaPath := filepath.Join(dir, "meta.json")
+	if err := os.Remove(metaPath); err != nil {
+		return err
+	}
+	if err := os.Remove(dir); err != nil {
+		// 父目录不可写等原因仍可能阻止最后的 rmdir，恢复元数据以便继续清理。
+		data, _ := json.Marshal(metadata)
+		return errors.Join(err, atomicWrite(metaPath, data))
+	}
+	return nil
+}
+
 type TrashFailure struct {
 	ID    string `json:"id"`
 	Error string `json:"error"`
@@ -35,12 +64,12 @@ func (v *Vault) PurgeTrash(days int64, now time.Time) (TrashPurgeResult, error)
 		if !trashIDPattern.MatchString(id) {
 			continue // 不删除非本程序管理的文件。
 		}
-		item, err := v.readTrashItem(id)
-		if err == nil && days > 0 && (item.DeletedAt > now.UnixMilli() || (now.UnixMilli()-item.DeletedAt)/int64(24*time.Hour/time.Millisecond) < days) {
+		metadata, err := v.readTrashMetadata(id)
+		if err == nil && days > 0 && (metadata.DeletedAt > now.UnixMilli() || (now.UnixMilli()-metadata.DeletedAt)/int64(24*time.Hour/time.Millisecond) < days) {
 			continue
 		}
 		if err == nil {
-			err = os.RemoveAll(filepath.Join(v.trash, id))
+			err = v.purgeTrashItemLocked(metadata)
 		}
 		if err != nil {
 			result.Failed = append(result.Failed, TrashFailure{ID: id, Error: err.Error()})

internal/vault/trash_test.go

@@ -1,6 +1,7 @@
 package vault
 
 import (
+	"bytes"
 	"encoding/json"
 	"errors"
 	"os"
@@ -10,6 +11,89 @@ import (
 	"time"
 )
 
+func TestTrashPurgeFailurePreservesMetadata(t *testing.T) {
+	if os.Geteuid() == 0 {
+		t.Skip("目录写权限测试需以普通用户运行；root 可绕过文件权限")
+	}
+	for _, operation := range []string{"single", "all", "expired"} {
+		for _, blocked := range []string{"payload", "parent"} {
+			t.Run(operation+"/"+blocked, func(t *testing.T) {
+				v := newVault(t)
+				if _, err := v.Write("folder/locked/note.md", []byte("content"), Precondition{}); err != nil {
+					t.Fatal(err)
+				}
+				setIcon(t, v, "folder", &TreeIcon{Kind: "emoji", Value: "📚"})
+				item, err := v.Delete("folder")
+				if err != nil {
+					t.Fatal(err)
+				}
+				metaPath := filepath.Join(v.trash, item.ID, "meta.json")
+				data, err := os.ReadFile(metaPath)
+				if err != nil {
+					t.Fatal(err)
+				}
+				var metadata trashMetadata
+				if err := json.Unmarshal(data, &metadata); err != nil {
+					t.Fatal(err)
+				}
+				metadata.DeletedAt = time.Now().Add(-40 * 24 * time.Hour).UnixMilli()
+				data, err = json.Marshal(metadata)
+				if err != nil {
+					t.Fatal(err)
+				}
+				if err := os.WriteFile(metaPath, data, 0600); err != nil {
+					t.Fatal(err)
+				}
+				locked := filepath.Join(v.trash, item.ID, "folder", "locked")
+				if blocked == "parent" {
+					locked = v.trash
+				}
+				if err := os.Chmod(locked, 0500); err != nil {
+					t.Fatal(err)
+				}
+				t.Cleanup(func() { os.Chmod(locked, 0755) })
+				purge := func() error {
+					if operation == "single" {
+						return v.Purge(item.ID)
+					}
+					days := int64(0)
+					if operation == "expired" {
+						days = 30
+					}
+					result, err := v.PurgeTrash(days, time.Now())
+					if err == nil && len(result.Failed) > 0 {
+						if len(result.Deleted) != 0 || len(result.Failed) != 1 || result.Failed[0].ID != item.ID {
+							t.Fatalf("部分失败结果错误: %+v", result)
+						}
+						return errors.New(result.Failed[0].Error)
+					}
+					return err
+				}
+				if err := purge(); err == nil {
+					t.Fatal("权限错误应报告失败")
+				}
+				after, err := os.ReadFile(metaPath)
+				if err != nil || !bytes.Equal(data, after) {
+					t.Fatalf("删除失败必须保留完整元数据: %v", err)
+				}
+				items, err := v.TrashList()
+				if err != nil || len(items) != 1 || items[0].ID != item.ID {
+					t.Fatalf("删除失败的条目必须仍可列出: %+v %v", items, err)
+				}
+				if err := os.Chmod(locked, 0755); err != nil {
+					t.Fatal(err)
+				}
+				if err := purge(); err != nil {
+					t.Fatalf("修复权限后应可继续清理: %v", err)
+				}
+				if _, err := os.Stat(filepath.Dir(metaPath)); !errors.Is(err, os.ErrNotExist) {
+					t.Fatalf("成功清理后不应残留目录: %v", err)
+				}
+			})
+		}
+	}
+}
+
 func trashAt(t *testing.T, v *Vault, path string, when time.Time) TrashItem {
 	t.Helper()
 	if _, err := v.Write(path, []byte("content"), Precondition{}); err != nil {

internal/vault/vault.go

@@ -748,10 +748,11 @@ func (v *Vault) Restore(id string) (item TrashItem, err error) {
 func (v *Vault) Purge(id string) error {
 	v.mu.Lock()
 	defer v.mu.Unlock()
-	if _, err := v.readTrashItem(id); err != nil {
+	metadata, err := v.readTrashMetadata(id)
+	if err != nil {
 		return err
 	}
-	return os.RemoveAll(filepath.Join(v.trash, id))
+	return v.purgeTrashItemLocked(metadata)
 }
 
 // ---- 资源 ----