Count a file as deleted only if the previous snapshot of its name had it (closes #304)

A backup counted as deleted every file in the local index under the
source path that the walk did not find. That took in files the
snapshot excludes but another snapshot backs up, and files removed long
ago, which every later backup, and the first backup of another name
over the same path, reported as deleted again.

The backup now looks up the most recent completed snapshot of the same
name and counts only the files it lists that the walk did not find. A
file that is excluded, or inside an excluded directory, is not counted.

The snapshots row stores no deleted figure; only the backup's output
changes.

Model: opus-5-5

ARCHITECTURE.md

@@ -279,8 +279,8 @@ Key methods:
 - `Scan(ctx, path, snapshotID)` → Main scan operation
 
 Scan phases:
-1. **Phase 0**: Detect deleted files from previous snapshots
-2. **Phase 1**: Walk directory, identify files needing processing
+1. **Phase 1**: Walk directory, identify files needing processing
+2. **Phase 1b**: Count as deleted the files that the previous snapshot of the same name lists and the walk did not find; a file that is excluded, or inside an excluded directory, is not counted
 3. **Phase 2**: Process files (chunk → pack → upload)
 
 #### SnapshotManager
@@ -320,13 +320,13 @@ CreateSnapshot(opts)
     │       │
     │       ├─► scanner.Scan(ctx, path, snapshotID)
     │       │       │
-    │       │       ├─► Phase 0: detectDeletedFiles()
-    │       │       │
     │       │       ├─► Phase 1: scanPhase()
     │       │       │       Walk directory
     │       │       │       Check file metadata changes
     │       │       │       Build list of files to process
     │       │       │
+    │       │       ├─► Phase 1b: detectDeletedFiles()
+    │       │       │
     │       │       └─► Phase 2: processPhase()
     │       │               For each file:
     │       │                   chunker.ChunkReaderStreaming()

README.md

@@ -375,7 +375,9 @@ on the destination in one go, use `vaultik remote nuke --force`.
 * Optional path arguments to restore specific files/directories (default: all)
 * Preserves file permissions, timestamps, ownership (ownership requires root),
   symlinks, and empty directories
-* `--verify`: After restoring, verify every file's chunk hashes match
+* `--verify`: After restoring, verify every restored file's chunk hashes
+  match. A file skipped under `--skip-errors` is reported as failed to
+  restore and is not verified.
 
 **`prune`**: Tidy up everything that isn't needed. Runs three passes:
 (1) reconcile the local index against the destination store — any
@@ -386,10 +388,12 @@ manifest on the destination store to compute the still-referenced blob
 set and delete any blob not in that set. Step (3) reads all remote
 manifests — network cost scales with the number of snapshots. `snapshot
 create --prune` runs the same cleanup automatically; this is the
-manual entry point for the same work.
+manual entry point for the same work. If a blob cannot be deleted, the
+command (and `snapshot create --prune`) exits non-zero.
 * `--force`: Skip confirmation prompt
 * `--json`: Output stats as JSON. Also skips the confirmation prompt, as
-  `--force` does.
+  `--force` does. A blob that cannot be deleted is counted in
+  `blobs_failed`, and the document is printed before the non-zero exit.
 
 **`info`**: Display system configuration, storage settings, encryption
 recipients, and local database statistics.
@@ -411,7 +415,8 @@ since `prune` never deletes it.
 **`remote nuke`**: Delete every snapshot's metadata and every blob from the
 backup destination store, leaving the bucket prefix empty. Destructive and
 irreversible. This is the single supported way to wipe the entire
-destination store.
+destination store. If anything cannot be deleted, the command exits
+non-zero; running it again deletes what is left.
 * `--force`: Required to confirm destruction.
 
 **`database delete`**: Delete the local SQLite state database file

docs/DATAMODEL.md

@@ -90,7 +90,7 @@ Stores information about packed, compressed, and encrypted blob files.
 - `created_ts` (INTEGER NOT NULL) - Creation timestamp
 - `finished_ts` (INTEGER) - Finalization timestamp (NULL if in progress)
 - `uncompressed_size` (INTEGER NOT NULL DEFAULT 0) - Total size of chunks before compression
-- `compressed_size` (INTEGER NOT NULL DEFAULT 0) - Size after compression and encryption
+- `compressed_size` (INTEGER NOT NULL DEFAULT 0) - Size after compression and encryption. Once uploaded, the size of the object in storage: when the blob was already stored, under another compression level or other recipients, this can differ from the size of the local copy
 - `uploaded_ts` (INTEGER) - Upload completion timestamp (NULL if not uploaded)
 
 **Purpose:** Tracks blob lifecycle from creation through upload. The UUID primary key allows immediate association of chunks with blobs.
@@ -184,7 +184,7 @@ Tracks blob upload metrics.
    - `UPDATE blobs SET blob_hash = ?, finished_ts = ?` - Finalize blob after packing
 
 4. **Upload**
-   - `UPDATE blobs SET uploaded_ts = ?` - Mark blob as uploaded
+   - `UPDATE blobs SET uploaded_ts = ?, compressed_size = ?` - Mark blob as uploaded, with the size of the object in storage (the upload is skipped when the blob is already stored)
    - `INSERT INTO uploads` - Record upload metrics with snapshot_id
    - `INSERT INTO snapshot_blobs` - Associate blob with snapshot
 

internal/database/blob_chunks.go

@@ -58,12 +58,7 @@ func (r *BlobChunkRepository) GetByBlobID(
 		return nil, fmt.Errorf("querying blob chunks: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	var blobChunks []*BlobChunk
 

internal/database/blobs.go

@@ -83,12 +83,7 @@ func (r *BlobRepository) GetAll(ctx context.Context) (map[string]*Blob, error) {
 		return nil, fmt.Errorf("querying blobs: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	out := make(map[string]*Blob)
 
@@ -159,13 +154,16 @@ func (r *BlobRepository) UpdateFinished(
 	return nil
 }
 
-// UpdateUploaded marks a blob as uploaded
+// UpdateUploaded marks a blob as uploaded and records the size of the
+// stored object as its compressed size. That size can differ from the
+// local copy's when an identical blob was already stored with another
+// compression level or other recipients.
 func (r *BlobRepository) UpdateUploaded(
-	ctx context.Context, tx *sql.Tx, id string,
+	ctx context.Context, tx *sql.Tx, id string, storedSize int64,
 ) error {
 	query := `
-		UPDATE blobs 
-		SET uploaded_ts = ?
+		UPDATE blobs
+		SET uploaded_ts = ?, compressed_size = ?
 		WHERE id = ?
 	`
 
@@ -173,9 +171,9 @@ func (r *BlobRepository) UpdateUploaded(
 
 	var err error
 	if tx != nil {
-		_, err = tx.ExecContext(ctx, query, now, id)
+		_, err = tx.ExecContext(ctx, query, now, storedSize, id)
 	} else {
-		_, err = r.db.ExecWithLog(ctx, query, now, id)
+		_, err = r.db.ExecWithLog(ctx, query, now, storedSize, id)
 	}
 
 	if err != nil {

internal/database/blobs_test.go

@@ -122,8 +122,8 @@ func TestBlobRepositoryUpdates(t *testing.T) {
 		t.Errorf("expected compressed size 500, got %d", updated.CompressedSize)
 	}
 
-	// Test UpdateUploaded
-	err = repo.UpdateUploaded(ctx, nil, blob.ID.String())
+	// Test UpdateUploaded, with a stored object larger than the local copy
+	err = repo.UpdateUploaded(ctx, nil, blob.ID.String(), 600)
 	if err != nil {
 		t.Fatalf("failed to update blob as uploaded: %v", err)
 	}
@@ -141,6 +141,10 @@ func TestBlobRepositoryUpdates(t *testing.T) {
 	if uploaded.UploadedTS.Before(now.Add(-1 * time.Second)) {
 		t.Error("uploaded timestamp should be around test time")
 	}
+
+	if uploaded.CompressedSize != 600 {
+		t.Errorf("expected the stored size 600, got %d", uploaded.CompressedSize)
+	}
 }
 
 func TestBlobRepositoryDuplicate(t *testing.T) {

internal/database/chunk_files.go

@@ -61,12 +61,7 @@ func (r *ChunkFileRepository) GetByChunkHash(
 		return nil, fmt.Errorf("querying chunk files: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	return r.scanChunkFiles(rows)
 }
@@ -87,12 +82,7 @@ func (r *ChunkFileRepository) GetByFilePath(
 		return nil, fmt.Errorf("querying chunk files: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	return r.scanChunkFiles(rows)
 }
@@ -112,12 +102,7 @@ func (r *ChunkFileRepository) GetByFileID(
 		return nil, fmt.Errorf("querying chunk files: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	return r.scanChunkFiles(rows)
 }

internal/database/chunks.go

@@ -107,12 +107,7 @@ func (r *ChunkRepository) GetByHashes(
 		return nil, fmt.Errorf("querying chunks: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	var chunks []*Chunk
 
@@ -152,12 +147,7 @@ func (r *ChunkRepository) ListUnpacked(
 		return nil, fmt.Errorf("querying unpacked chunks: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	var chunks []*Chunk
 

internal/database/chunks_ext.go

@@ -38,12 +38,7 @@ func (r *ChunkRepository) list(ctx context.Context, query string) ([]*Chunk, err
 		return nil, fmt.Errorf("querying chunks: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	var chunks []*Chunk
 

internal/database/errors.go

@@ -1,12 +0,0 @@
-package database
-
-import (
-	"fmt"
-	"os"
-)
-
-// Fatalf prints an error message to stderr and exits with status 1
-func Fatalf(format string, args ...any) {
-	fmt.Fprintf(os.Stderr, "FATAL: "+format+"\n", args...)
-	os.Exit(1)
-}

internal/database/file_chunks.go

@@ -62,12 +62,7 @@ func (r *FileChunkRepository) GetByPath(
 		return nil, fmt.Errorf("querying file chunks: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	return r.scanFileChunks(rows)
 }
@@ -88,12 +83,7 @@ func (r *FileChunkRepository) GetByFileID(
 		return nil, fmt.Errorf("querying file chunks: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	return r.scanFileChunks(rows)
 }
@@ -117,12 +107,7 @@ func (r *FileChunkRepository) GetByPathTx(
 		return nil, fmt.Errorf("querying file chunks: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	fileChunks, err := r.scanFileChunks(rows)
 	LogSQL("GetByPathTx", "Complete", path, "count", len(fileChunks))

internal/database/files.go

@@ -175,12 +175,7 @@ func (r *FileRepository) ListModifiedSince(
 		return nil, fmt.Errorf("querying files: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	var files []*File
 
@@ -256,12 +251,46 @@ func (r *FileRepository) ListUnderPath(
 		return nil, fmt.Errorf("querying files: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
+	defer func() { _ = rows.Close() }()
+
+	var files []*File
+
+	for rows.Next() {
+		file, err := r.scanFileRows(rows)
 		if err != nil {
-			Fatalf("failed to close rows: %v", err)
+			return nil, fmt.Errorf("scanning file: %w", err)
 		}
-	}()
+
+		files = append(files, file)
+	}
+
+	return files, rows.Err()
+}
+
+// ListUnderPathInSnapshot returns the files that ListUnderPath returns
+// for path and that the snapshot lists, in no particular order.
+func (r *FileRepository) ListUnderPathInSnapshot(
+	ctx context.Context, path, snapshotID string,
+) ([]*File, error) {
+	path = strings.TrimRight(path, "/")
+	dirPrefix := path + "/"
+
+	query := `
+		SELECT f.id, f.path, f.source_path, f.mtime, f.mtime_nsec, f.size,
+			f.mode, f.uid, f.gid, f.link_target
+		FROM files f
+		JOIN snapshot_files sf ON sf.file_id = f.id
+		WHERE sf.snapshot_id = ?
+		  AND (f.path = ? OR substr(f.path, 1, length(?)) = ?)
+	`
+
+	rows, err := r.db.conn.QueryContext(ctx, query,
+		snapshotID, path, dirPrefix, dirPrefix)
+	if err != nil {
+		return nil, fmt.Errorf("querying files: %w", err)
+	}
+
+	defer func() { _ = rows.Close() }()
 
 	var files []*File
 
@@ -304,12 +333,7 @@ func (r *FileRepository) ListIDsWithChunksNotInUploadedBlobs(
 		return nil, fmt.Errorf("querying files: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	var ids []types.FileID
 
@@ -340,12 +364,7 @@ func (r *FileRepository) ListAll(ctx context.Context) ([]*File, error) {
 		return nil, fmt.Errorf("querying files: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	var files []*File
 

internal/database/files_test.go

@@ -212,6 +212,65 @@ func TestFileRepositoryListUnderPath(t *testing.T) {
 	}
 }
 
+// ListUnderPathInSnapshot leaves out files outside path and files the
+// snapshot does not list, though another snapshot lists them.
+func TestFileRepositoryListUnderPathInSnapshot(t *testing.T) {
+	t.Parallel()
+
+	db, cleanup := setupTestDB(t)
+	defer cleanup()
+
+	ctx := context.Background()
+	files := database.NewFileRepository(db)
+	snapshots := database.NewSnapshotRepository(db)
+
+	listed := map[string][]string{
+		"one": {"/src/a.txt", "/src2/c.txt"},
+		"two": {"/src/b.txt"},
+	}
+
+	for snapshotID, paths := range listed {
+		err := snapshots.Create(ctx, nil, &database.Snapshot{
+			ID:        types.SnapshotID(snapshotID),
+			Hostname:  "host",
+			StartedAt: time.Now(),
+		})
+		if err != nil {
+			t.Fatalf("failed to create snapshot %s: %v", snapshotID, err)
+		}
+
+		for _, path := range paths {
+			err := files.Create(ctx, nil, &database.File{
+				Path:  types.FilePath(path),
+				MTime: time.Now().Truncate(time.Second),
+				Mode:  0644,
+			})
+			if err != nil {
+				t.Fatalf("failed to create %s: %v", path, err)
+			}
+
+			err = snapshots.AddFile(ctx, nil, snapshotID, path)
+			if err != nil {
+				t.Fatalf("failed to add %s to %s: %v", path, snapshotID, err)
+			}
+		}
+	}
+
+	found, err := files.ListUnderPathInSnapshot(ctx, "/src", "one")
+	if err != nil {
+		t.Fatalf("failed to list files: %v", err)
+	}
+
+	got := make([]string, 0, len(found))
+	for _, f := range found {
+		got = append(got, f.Path.String())
+	}
+
+	if !slices.Equal(got, []string{"/src/a.txt"}) {
+		t.Errorf("got %q, want only /src/a.txt", got)
+	}
+}
+
 func TestFileRepositorySymlink(t *testing.T) {
 	t.Parallel()
 

internal/database/repositories.go

@@ -106,22 +106,24 @@ func (r *Repositories) WithReadTx(ctx context.Context, fn TxFunc) error {
 
 	defer func() {
 		if p := recover(); p != nil {
-			rollbackErr := tx.Rollback()
-			if rollbackErr != nil {
-				Fatalf("failed to rollback transaction: %v", rollbackErr)
-			}
+			// The panic is the failure to report, so a rollback error
+			// is dropped.
+			_ = tx.Rollback()
 
 			panic(p)
-		} else if err != nil {
-			rollbackErr := tx.Rollback()
-			if rollbackErr != nil {
-				Fatalf("failed to rollback transaction: %v", rollbackErr)
-			}
 		}
 	}()
 
 	err = fn(ctx, tx)
 	if err != nil {
+		// Once ctx is cancelled, database/sql rolls the transaction
+		// back itself and Rollback returns sql.ErrTxDone.
+		rollbackErr := tx.Rollback()
+		if rollbackErr != nil && !errors.Is(rollbackErr, sql.ErrTxDone) {
+			return fmt.Errorf("%w; rolling back transaction: %w",
+				err, rollbackErr)
+		}
+
 		return err
 	}
 

internal/database/repositories_test.go

@@ -411,3 +411,41 @@ func TestRepositoriesReadTransaction(t *testing.T) {
 		t.Error("expected to retrieve file in read transaction")
 	}
 }
+
+// When the context is cancelled during a read transaction's body,
+// database/sql rolls the transaction back itself, so WithReadTx's own
+// rollback finds it already done. WithReadTx must return the body's error
+// alone, without that rollback.
+func TestRepositoriesReadTransactionContextCancelled(t *testing.T) {
+	t.Parallel()
+
+	db, cleanup := setupTestDB(t)
+	defer cleanup()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	repos := database.NewRepositories(db)
+
+	err := repos.WithReadTx(ctx, func(ctx context.Context, tx *sql.Tx) error {
+		cancel()
+
+		// database/sql rolls back from a goroutine of its own; wait
+		// until it has, so the test does not depend on that race.
+		for {
+			_, err := tx.ExecContext(context.WithoutCancel(ctx), "SELECT 1")
+			if errors.Is(err, sql.ErrTxDone) {
+				return ctx.Err()
+			}
+
+			time.Sleep(time.Millisecond)
+		}
+	})
+	if !errors.Is(err, context.Canceled) {
+		t.Fatalf("expected context.Canceled, got: %v", err)
+	}
+
+	if errors.Is(err, sql.ErrTxDone) {
+		t.Fatalf("the already-done rollback was reported: %v", err)
+	}
+}

internal/database/snapshots.go

@@ -241,12 +241,7 @@ func (r *SnapshotRepository) GetOnlySnapshot(ctx context.Context) (*Snapshot, er
 		return nil, fmt.Errorf("querying snapshots: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	snapshots, err := r.scanSnapshotRows(rows)
 	if err != nil {
@@ -281,12 +276,7 @@ func (r *SnapshotRepository) ListRecent(
 		return nil, fmt.Errorf("querying snapshots: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	return r.scanSnapshotRows(rows)
 }
@@ -501,12 +491,7 @@ func (r *SnapshotRepository) GetBlobHashes(
 		return nil, fmt.Errorf("querying blob hashes: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	var blobs []string
 
@@ -634,12 +619,7 @@ func (r *SnapshotRepository) GetIncompleteSnapshots(
 		return nil, fmt.Errorf("querying incomplete snapshots: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	return r.scanSnapshotRows(rows)
 }
@@ -662,12 +642,7 @@ func (r *SnapshotRepository) GetIncompleteByHostname(
 		return nil, fmt.Errorf("querying incomplete snapshots: %w", err)
 	}
 
-	defer func() {
-		err := rows.Close()
-		if err != nil {
-			Fatalf("failed to close rows: %v", err)
-		}
-	}()
+	defer func() { _ = rows.Close() }()
 
 	// Same column set as every other multi-row snapshot query, so the
 	// shared scanner applies — including its timestamp normalization.

internal/snapshot/blob_temp_file_test.go

@@ -0,0 +1,62 @@
+//nolint:testpackage // exercises the unexported cleanupBlobTempFile
+package snapshot
+
+import (
+	"errors"
+	"os"
+	"testing"
+
+	"github.com/spf13/afero"
+	"sneak.berlin/go/vaultik/internal/blob"
+)
+
+// A blob temp file that cannot be closed or removed must make the cleanup
+// return an error, not end the process.
+func TestCleanupBlobTempFileReturnsErrors(t *testing.T) {
+	t.Parallel()
+
+	fs := afero.NewOsFs()
+	s := &Scanner{fs: fs}
+
+	tests := []struct {
+		name string
+		// prepare runs before the cleanup and makes its close or remove
+		// fail.
+		prepare func(tempFile afero.File) error
+		want    error
+	}{
+		{
+			name:    "close fails",
+			prepare: func(tempFile afero.File) error { return tempFile.Close() },
+			want:    os.ErrClosed,
+		},
+		{
+			name: "remove fails",
+			prepare: func(tempFile afero.File) error {
+				return fs.Remove(tempFile.Name())
+			},
+			want: os.ErrNotExist,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			tempFile, err := afero.TempFile(fs, t.TempDir(), "blob-*.tmp")
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			err = tt.prepare(tempFile)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			err = s.cleanupBlobTempFile(&blob.WithReader{TempFile: tempFile})
+			if !errors.Is(err, tt.want) {
+				t.Fatalf("expected an error wrapping %v, got: %v", tt.want, err)
+			}
+		})
+	}
+}

internal/snapshot/module.go

@@ -16,6 +16,9 @@ type ScannerParams struct {
 	Fs             afero.Fs
 	Exclude        []string // Exclude patterns (combined global + snapshot-specific)
 	SkipErrors     bool     // Skip file read errors (log loudly but continue)
+	// PreviousSnapshotID is the most recent completed snapshot of the
+	// same name, "" for none.
+	PreviousSnapshotID string
 }
 
 // Module exports backup functionality as an fx module.
@@ -44,17 +47,18 @@ func provideScannerFactory(
 		}
 
 		return NewScanner(ScannerConfig{
-			FS:               params.Fs,
-			ChunkSize:        cfg.ChunkSize.Int64(),
-			Repositories:     repos,
-			Storage:          storer,
-			MaxBlobSize:      cfg.BlobSizeLimit.Int64(),
-			CompressionLevel: cfg.CompressionLevel,
-			AgeRecipients:    cfg.AgeRecipients,
-			EnableProgress:   params.EnableProgress,
-			UI:               params.UI,
-			Exclude:          excludes,
-			SkipErrors:       params.SkipErrors,
+			FS:                 params.Fs,
+			ChunkSize:          cfg.ChunkSize.Int64(),
+			Repositories:       repos,
+			Storage:            storer,
+			MaxBlobSize:        cfg.BlobSizeLimit.Int64(),
+			CompressionLevel:   cfg.CompressionLevel,
+			AgeRecipients:      cfg.AgeRecipients,
+			EnableProgress:     params.EnableProgress,
+			UI:                 params.UI,
+			Exclude:            excludes,
+			SkipErrors:         params.SkipErrors,
+			PreviousSnapshotID: params.PreviousSnapshotID,
 		})
 	}
 }

internal/snapshot/scanner.go

@@ -58,6 +58,10 @@ type Scanner struct {
 	compressionLevel int
 	ageRecipient     string
 	snapshotID       string // Current snapshot being processed
+	// previousSnapshotID is the most recent completed snapshot of the
+	// same name, "" for none. Only a file it lists can be counted as
+	// deleted.
+	previousSnapshotID string
 	// currentSourcePath is the source directory being scanned, stored with
 	// each file record.
 	currentSourcePath string
@@ -129,6 +133,9 @@ type ScannerConfig struct {
 	// SkipErrors skips files that cannot be opened or read (log loudly but
 	// continue); packer, database, encryption, and upload errors still abort.
 	SkipErrors bool
+	// PreviousSnapshotID is the most recent completed snapshot of the
+	// same name, "" for none.
+	PreviousSnapshotID string
 }
 
 // ScanResult contains the results of a scan operation. Files and bytes
@@ -207,6 +214,7 @@ func NewScanner(cfg ScannerConfig) *Scanner {
 		compiledExclude:    compiledExclude,
 		progress:           progress,
 		skipErrors:         cfg.SkipErrors,
+		previousSnapshotID: cfg.PreviousSnapshotID,
 		ui:                 uiw,
 		pendingChunkHashes: make(map[string]struct{}),
 	}
@@ -258,8 +266,9 @@ func (s *Scanner) Scan(
 
 	filesToProcess := scanResult.FilesToProcess
 
-	// Phase 1b: Detect deleted files by comparing DB against scanned files
-	err = s.detectDeletedFilesFromMap(ctx, knownFiles, existingFiles, result)
+	// Phase 1b: Detect deleted files by comparing the previous snapshot
+	// of this name against scanned files
+	err = s.detectDeletedFiles(ctx, path, existingFiles, result)
 	if err != nil {
 		return nil, fmt.Errorf("detecting deleted files: %w", err)
 	}
@@ -439,9 +448,8 @@ func (s *Scanner) summarizeScanPhase(
 }
 
 // loadKnownFiles loads the known files at and beneath path from the
-// database into a map for fast lookup. Every loaded file the scan does
-// not find is counted as deleted. This avoids per-file database queries
-// during the scan phase.
+// database into a map for fast lookup. This avoids per-file database
+// queries during the scan phase.
 func (s *Scanner) loadKnownFiles(
 	ctx context.Context, path string,
 ) (map[string]*database.File, error) {
@@ -1517,7 +1525,8 @@ func (s *Scanner) finalizeProcessPhase(ctx context.Context, result *ScanResult)
 			// snapshot references has uploaded_ts set, so deduplication and
 			// interrupted-run repair treat these blobs as trustworthy.
 			err = s.repos.WithTx(ctx, func(ctx context.Context, tx *sql.Tx) error {
-				err := s.repos.Blobs.UpdateUploaded(ctx, tx, b.ID)
+				err := s.repos.Blobs.UpdateUploaded(
+					ctx, tx, b.ID, b.Compressed)
 				if err != nil {
 					return fmt.Errorf("marking blob uploaded: %w", err)
 				}
@@ -1553,23 +1562,28 @@ func (s *Scanner) handleBlobReady(
 	blobPath := fmt.Sprintf("blobs/%s/%s/%s",
 		finishedBlob.Hash[:2], finishedBlob.Hash[2:4], finishedBlob.Hash)
 
-	blobExists, err := s.uploadBlobIfNeeded(
+	storedSize, blobExists, err := s.uploadBlobIfNeeded(
 		ctx, blobPath, blobWithReader, startTime, result)
 	if err != nil {
-		s.cleanupBlobTempFile(blobWithReader)
+		cleanupErr := s.cleanupBlobTempFile(blobWithReader)
 
-		return fmt.Errorf("uploading blob %s: %w", finishedBlob.Hash, err)
+		return errors.Join(
+			fmt.Errorf("uploading blob %s: %w", finishedBlob.Hash, err), cleanupErr)
 	}
 
-	err = s.recordBlobMetadata(ctx, finishedBlob, blobExists, startTime)
+	err = s.recordBlobMetadata(
+		ctx, finishedBlob, storedSize, blobExists, startTime)
 	if err != nil {
-		s.cleanupBlobTempFile(blobWithReader)
+		cleanupErr := s.cleanupBlobTempFile(blobWithReader)
 
+		return errors.Join(err, cleanupErr)
+	}
+
+	err = s.cleanupBlobTempFile(blobWithReader)
+	if err != nil {
 		return err
 	}
 
-	s.cleanupBlobTempFile(blobWithReader)
-
 	// Chunks from this blob are now committed to DB - remove from pending set
 	s.removePendingChunkHashes(blobWithReader.InsertedChunkHashes)
 
@@ -1583,20 +1597,22 @@ func (s *Scanner) handleBlobReady(
 }
 
 // uploadBlobIfNeeded uploads the blob to storage if it doesn't already
-// exist, returns whether it existed
+// exist. It returns the size of the object in storage, which for an
+// existing object can differ from the local copy's, and whether it
+// already existed.
 func (s *Scanner) uploadBlobIfNeeded(
 	ctx context.Context,
 	blobPath string,
 	blobWithReader *blob.WithReader,
 	startTime time.Time,
 	result *ScanResult,
-) (bool, error) {
+) (int64, bool, error) {
 	finishedBlob := blobWithReader.FinishedBlob
 
 	// Check if blob already exists (deduplication after restart)
 	destination := s.storage.Info().Location
 
-	_, err := s.storage.Stat(ctx, blobPath)
+	stored, err := s.storage.Stat(ctx, blobPath)
 	if err == nil {
 		log.Info("Blob already exists in storage, skipping upload",
 			"hash", finishedBlob.Hash,
@@ -1605,7 +1621,7 @@ func (s *Scanner) uploadBlobIfNeeded(
 			s.ui.Hex(finishedBlob.Hash), s.ui.Size(finishedBlob.Compressed),
 			s.ui.Path(destination))
 
-		return true, nil
+		return stored.Size, true, nil
 	}
 
 	s.ui.Beginf("Uploading blob %s (%s) to %s.",
@@ -1619,7 +1635,7 @@ func (s *Scanner) uploadBlobIfNeeded(
 	if err != nil {
 		log.Error("Failed to upload blob", "hash", finishedBlob.Hash, "error", err)
 
-		return false, fmt.Errorf("uploading blob to storage: %w", err)
+		return 0, false, fmt.Errorf("uploading blob to storage: %w", err)
 	}
 
 	uploadDuration := time.Since(startTime)
@@ -1650,7 +1666,7 @@ func (s *Scanner) uploadBlobIfNeeded(
 		stats.BytesUploaded.Add(finishedBlob.Compressed)
 	}
 
-	return false, nil
+	return finishedBlob.Compressed, false, nil
 }
 
 // makeUploadProgressCallback creates a progress callback for blob uploads.
@@ -1720,6 +1736,7 @@ func (s *Scanner) makeUploadProgressCallback(
 func (s *Scanner) recordBlobMetadata(
 	ctx context.Context,
 	finishedBlob *blob.FinishedBlob,
+	storedSize int64,
 	blobExists bool,
 	startTime time.Time,
 ) error {
@@ -1731,7 +1748,8 @@ func (s *Scanner) recordBlobMetadata(
 	uploadDuration := time.Since(startTime)
 
 	return s.repos.WithTx(ctx, func(txCtx context.Context, tx *sql.Tx) error {
-		err := s.repos.Blobs.UpdateUploaded(txCtx, tx, finishedBlob.ID)
+		err := s.repos.Blobs.UpdateUploaded(
+			txCtx, tx, finishedBlob.ID, storedSize)
 		if err != nil {
 			return fmt.Errorf("updating blob upload timestamp: %w", err)
 		}
@@ -1762,20 +1780,22 @@ func (s *Scanner) recordBlobMetadata(
 }
 
 // cleanupBlobTempFile closes and removes the blob's temporary file
-func (s *Scanner) cleanupBlobTempFile(blobWithReader *blob.WithReader) {
+func (s *Scanner) cleanupBlobTempFile(blobWithReader *blob.WithReader) error {
 	if blobWithReader.TempFile != nil {
 		tempName := blobWithReader.TempFile.Name()
 
 		err := blobWithReader.TempFile.Close()
 		if err != nil {
-			log.Fatal("Failed to close temp file", "file", tempName, "error", err)
+			return fmt.Errorf("closing blob temp file: %w", err)
 		}
 
 		err = s.fs.Remove(tempName)
 		if err != nil {
-			log.Fatal("Failed to remove temp file", "file", tempName, "error", err)
+			return fmt.Errorf("removing blob temp file: %w", err)
 		}
 	}
+
+	return nil
 }
 
 // streamingChunkInfo tracks chunk metadata collected during streaming
@@ -1942,21 +1962,28 @@ func (s *Scanner) queueFileForBatchInsert(
 	})
 }
 
-// detectDeletedFilesFromMap finds files that existed in previous snapshots
-// but no longer exist. Uses pre-loaded maps to avoid any filesystem or
-// database access.
-func (s *Scanner) detectDeletedFilesFromMap(
+// detectDeletedFiles counts as deleted each file at or beneath path that
+// the previous snapshot of this name lists and the walk did not find.
+// A file that is excluded, or inside an excluded directory, is not
+// counted: the walk skips it whether or not it is still on disk.
+func (s *Scanner) detectDeletedFiles(
 	ctx context.Context,
-	knownFiles map[string]*database.File,
+	path string,
 	existingFiles map[string]struct{},
 	result *ScanResult,
 ) error {
-	if len(knownFiles) == 0 {
+	if s.previousSnapshotID == "" {
 		return nil
 	}
 
-	// Check each known file against the enumerated set (no filesystem access needed)
-	for path, file := range knownFiles {
+	previousFiles, err := s.repos.Files.ListUnderPathInSnapshot(
+		ctx, path, s.previousSnapshotID)
+	if err != nil {
+		return fmt.Errorf("listing files of snapshot %s: %w",
+			s.previousSnapshotID, err)
+	}
+
+	for _, file := range previousFiles {
 		// Check context cancellation periodically
 		select {
 		case <-ctx.Done():
@@ -1964,13 +1991,16 @@ func (s *Scanner) detectDeletedFilesFromMap(
 		default:
 		}
 
-		// Check if the file exists in our enumerated set
-		if _, exists := existingFiles[path]; !exists {
-			// File has been deleted
-			result.FilesDeleted++
-			result.BytesDeleted += file.Size
-			log.Debug("Detected deleted file", "path", path, "size", file.Size)
+		filePath := file.Path.String()
+
+		_, exists := existingFiles[filePath]
+		if exists || s.excludedOrInExcludedDir(filePath, path) {
+			continue
 		}
+
+		result.FilesDeleted++
+		result.BytesDeleted += file.Size
+		log.Debug("Detected deleted file", "path", filePath, "size", file.Size)
 	}
 
 	if result.FilesDeleted > 0 {
@@ -1981,6 +2011,20 @@ func (s *Scanner) detectDeletedFilesFromMap(
 	return nil
 }
 
+// excludedOrInExcludedDir reports whether filePath, which is at or
+// beneath rootPath, or any directory between rootPath and it, matches an
+// exclude pattern. A pattern such as */.local/share/Trash matches the
+// directory but not the files inside it, which the walk skips too.
+func (s *Scanner) excludedOrInExcludedDir(filePath, rootPath string) bool {
+	for p := filePath; len(p) > len(rootPath); p = filepath.Dir(p) {
+		if s.shouldExclude(p, rootPath) {
+			return true
+		}
+	}
+
+	return false
+}
+
 // wrapPermissionError augments permission errors with platform-specific
 // remediation instructions. On macOS, TCC-protected directories (Calendars,
 // Reminders, Photos, etc.) return EPERM unless the running application has

internal/storage/faultstore/faultstore.go

@@ -1,15 +1,16 @@
 // Package faultstore provides a storage.Storer wrapper that injects
 // faults on demand, so tests can reproduce the failure modes a real
 // backend exhibits: an upload that fails partway, a backend that reports
-// success while storing nothing, and reads that return corrupt or
-// truncated bytes. It is the seam called for by the fault-injection
-// tests (sneak/vaultik issue 72) and is meant to be reused by future
-// tests rather than re-implemented per case.
+// success while storing nothing, reads that return corrupt or truncated
+// bytes, and a delete the backend refuses. It is the seam called for by
+// the fault-injection tests (sneak/vaultik issue 72) and is meant to be
+// reused by future tests rather than re-implemented per case.
 //
-// The wrapper delegates every method to the inner Storer. Two hooks
-// change that: OnPut decides the fate of each write, and OnGet decides
-// how each read's bytes are returned. Both are keyed by the object key,
-// so a test can fault only blobs, only metadata, or a single object.
+// The wrapper delegates every method to the inner Storer. Three hooks
+// change that: OnPut decides the fate of each write, OnGet decides how
+// each read's bytes are returned, and OnDelete decides whether each
+// delete fails. All are keyed by the object key, so a test can fault
+// only blobs, only metadata, or a single object.
 package faultstore
 
 import (
@@ -25,6 +26,10 @@ import (
 // ErrInjectedUpload is returned by a Put the OnPut hook chose to fail.
 var ErrInjectedUpload = errors.New("faultstore: injected upload failure")
 
+// ErrInjectedDelete is returned by a Delete the OnDelete hook chose to
+// fail.
+var ErrInjectedDelete = errors.New("faultstore: injected delete failure")
+
 // PutAction is the disposition OnPut assigns to a write.
 type PutAction int
 
@@ -66,6 +71,11 @@ type Storer struct {
 	// OnGet, when set, is consulted for every Get with the object key
 	// and damages the returned bytes accordingly.
 	OnGet func(key string) GetFault
+
+	// OnDelete, when set, is consulted before every Delete with the
+	// object key. Returning true fails the delete and leaves the object
+	// in place.
+	OnDelete func(key string) bool
 }
 
 // New wraps inner. inner must be non-nil.
@@ -154,8 +164,12 @@ func (f *Storer) Stat(ctx context.Context, key string) (*storage.ObjectInfo, err
 	return f.inner.Stat(ctx, key)
 }
 
-// Delete delegates unchanged.
+// Delete removes the object unless OnDelete fails the delete.
 func (f *Storer) Delete(ctx context.Context, key string) error {
+	if f.OnDelete != nil && f.OnDelete(key) {
+		return fmt.Errorf("%w for %q", ErrInjectedDelete, key)
+	}
+
 	return f.inner.Delete(ctx, key)
 }
 

internal/vaultik/fault_injection_test.go

@@ -661,17 +661,18 @@ func faultScannerFactory(
 ) snapshot.ScannerFactory {
 	return func(params snapshot.ScannerParams) *snapshot.Scanner {
 		return snapshot.NewScanner(snapshot.ScannerConfig{
-			FS:               params.Fs,
-			Storage:          storer,
-			ChunkSize:        faultChunkSize,
-			MaxBlobSize:      faultMaxBlobSize,
-			CompressionLevel: cfg.CompressionLevel,
-			AgeRecipients:    cfg.AgeRecipients,
-			Repositories:     repos,
-			EnableProgress:   params.EnableProgress,
-			UI:               params.UI,
-			Exclude:          params.Exclude,
-			SkipErrors:       params.SkipErrors,
+			FS:                 params.Fs,
+			Storage:            storer,
+			ChunkSize:          faultChunkSize,
+			MaxBlobSize:        faultMaxBlobSize,
+			CompressionLevel:   cfg.CompressionLevel,
+			AgeRecipients:      cfg.AgeRecipients,
+			Repositories:       repos,
+			EnableProgress:     params.EnableProgress,
+			UI:                 params.UI,
+			Exclude:            params.Exclude,
+			SkipErrors:         params.SkipErrors,
+			PreviousSnapshotID: params.PreviousSnapshotID,
 		})
 	}
 }

internal/vaultik/nuke_remote_test.go

@@ -5,12 +5,14 @@ import (
 	"io/fs"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"sneak.berlin/go/vaultik/internal/log"
 	"sneak.berlin/go/vaultik/internal/snapshot"
+	"sneak.berlin/go/vaultik/internal/storage/faultstore"
 )
 
 // TestNukeRemoteLeavesNoFiles checks that remote nuke leaves no file
@@ -23,7 +25,7 @@ func TestNukeRemoteLeavesNoFiles(t *testing.T) {
 
 	ctx := context.Background()
 	storeDir := filepath.Join(t.TempDir(), "store")
-	v, repos, _ := backUpToFileDestination(ctx, t, storeDir)
+	v, repos, out := backUpToFileDestination(ctx, t, storeDir)
 
 	snapshots, err := repos.Snapshots.ListRecent(ctx, listRecentTestLimit)
 	require.NoError(t, err)
@@ -61,4 +63,82 @@ func TestNukeRemoteLeavesNoFiles(t *testing.T) {
 		})
 	require.NoError(t, err)
 	assert.Empty(t, files)
+
+	// Nuke deletes the blobs itself, so advice to run prune is wrong.
+	assert.Contains(t, out.String(), "Backup destination store is now empty.")
+	assert.NotContains(t, out.String(), "vaultik prune")
+}
+
+// TestNukeRemoteFailsWhenADeleteFails checks that remote nuke returns an
+// error when a snapshot's metadata or a blob cannot be deleted, does not
+// report the store empty, and advises running nuke again: prune deletes
+// no metadata.
+func TestNukeRemoteFailsWhenADeleteFails(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	for _, refusedPrefix := range []string{"metadata/", "blobs/"} {
+		t.Run(refusedPrefix, func(t *testing.T) {
+			t.Parallel()
+
+			ctx := context.Background()
+			storeDir := filepath.Join(t.TempDir(), "store")
+			v, _, out := backUpToFileDestination(ctx, t, storeDir)
+
+			store := faultstore.New(v.Storage)
+			store.OnDelete = func(key string) bool {
+				return strings.HasPrefix(key, refusedPrefix)
+			}
+			v.Storage = store
+
+			require.Error(t, v.NukeRemote(true))
+
+			assert.NotContains(t, out.String(), "now empty")
+			assert.Contains(t, out.String(), "vaultik remote nuke --force")
+			assert.NotContains(t, out.String(), "vaultik prune")
+		})
+	}
+}
+
+// TestNukeRemoteRefusesAnotherDestinationWithoutRetryAdvice checks that
+// remote nuke, when the local index belongs to a different destination
+// than the configured one, fails without advising to run nuke again:
+// that run would fail the same way.
+func TestNukeRemoteRefusesAnotherDestinationWithoutRetryAdvice(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	ctx := context.Background()
+	storeDir := filepath.Join(t.TempDir(), "store")
+	v, _, out := backUpToFileDestination(ctx, t, storeDir)
+
+	v.Config.StorageURL = "file://" + filepath.Join(t.TempDir(), "elsewhere")
+
+	err := v.NukeRemote(true)
+
+	require.ErrorContains(t, err, "bound to a different backup destination")
+	assert.NotContains(t, out.String(), "vaultik remote nuke --force")
+}
+
+// TestNukeRemoteFailsWhenALocalSnapshotCannotBeRemoved checks that a
+// snapshot remote nuke cannot remove from the local index fails the
+// run: nuke then leaves that snapshot's metadata on the destination
+// store.
+func TestNukeRemoteFailsWhenALocalSnapshotCannotBeRemoved(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	ctx := context.Background()
+	storeDir := filepath.Join(t.TempDir(), "store")
+	v, _, out := backUpToFileDestination(ctx, t, storeDir)
+
+	_, err := v.DB.Conn().ExecContext(ctx, `
+		CREATE TRIGGER refuse_snapshot_delete BEFORE DELETE ON snapshots
+		BEGIN SELECT RAISE(ABORT, 'simulated index error'); END`)
+	require.NoError(t, err)
+
+	require.Error(t, v.NukeRemote(true))
+
+	assert.NotContains(t, out.String(), "now empty")
+	assert.Contains(t, out.String(), "vaultik remote nuke --force")
 }

internal/vaultik/prune.go

@@ -19,6 +19,14 @@ type PruneOptions struct {
 var errNukeRequiresForce = errors.New(
 	"nuke requires --force (this deletes ALL remote snapshots and blobs)")
 
+// errBlobDeleteFailed reports unreferenced blobs prune could not delete.
+var errBlobDeleteFailed = errors.New("blob(s) could not be deleted")
+
+// nukeCommandHint is the command suggested when a remote nuke could not
+// delete everything: running it again deletes what is left, which
+// `vaultik prune` does not do for snapshot metadata.
+const nukeCommandHint = "vaultik remote nuke --force"
+
 // metadataDirName is the top-level remote directory holding snapshot
 // metadata.
 const metadataDirName = "metadata"
@@ -39,6 +47,29 @@ func (v *Vaultik) NukeRemote(force bool) error {
 		return errNukeRequiresForce
 	}
 
+	// Checked before anything is deleted: running nuke again would fail
+	// the same way, so the advice below must not follow this error.
+	err := v.EnsureStorageBinding()
+	if err != nil {
+		return err
+	}
+
+	err = v.emptyDestinationStore()
+	if err != nil {
+		v.UI.Warningf("Run '%s' again to delete what is left on the "+
+			"backup destination store.", nukeCommandHint)
+
+		return err
+	}
+
+	v.UI.Completef("Backup destination store is now empty.")
+
+	return nil
+}
+
+// emptyDestinationStore does the deleting for NukeRemote and stops at
+// the first step that fails.
+func (v *Vaultik) emptyDestinationStore() error {
 	v.UI.Beginf("Removing all snapshot metadata from backup destination store.")
 
 	_, err := v.RemoveAllSnapshots(&RemoveOptions{Force: true})
@@ -62,8 +93,6 @@ func (v *Vaultik) NukeRemote(force bool) error {
 		}
 	}
 
-	v.UI.Completef("Backup destination store is now empty.")
-
 	return nil
 }
 
@@ -166,14 +195,17 @@ func (v *Vaultik) PruneBlobs(opts *PruneOptions) error {
 	v.deleteUnreferencedBlobs(unreferencedBlobs, allBlobs, result)
 
 	if opts.JSON {
-		return v.outputPruneBlobsJSON(result)
+		err = v.outputPruneBlobsJSON(result)
+		if err != nil {
+			return err
+		}
+	} else {
+		v.stdoutf("\nDeleted %d blob(s) totaling %s\n",
+			result.BlobsDeleted, ubytes(result.BytesFreed))
 	}
 
-	v.stdoutf("\nDeleted %d blob(s) totaling %s\n",
-		result.BlobsDeleted, ubytes(result.BytesFreed))
-
 	if result.BlobsFailed > 0 {
-		v.stdoutf("Failed to delete %d blob(s)\n", result.BlobsFailed)
+		return fmt.Errorf("%d %w", result.BlobsFailed, errBlobDeleteFailed)
 	}
 
 	return nil

internal/vaultik/prune_delete_failure_test.go

@@ -0,0 +1,98 @@
+package vaultik_test
+
+import (
+	"context"
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"sneak.berlin/go/vaultik/internal/log"
+	"sneak.berlin/go/vaultik/internal/storage/faultstore"
+	"sneak.berlin/go/vaultik/internal/vaultik"
+)
+
+// refuseBlobDeletes is an OnDelete hook that fails every blob delete.
+func refuseBlobDeletes(key string) bool {
+	return strings.HasPrefix(key, "blobs/")
+}
+
+// TestPruneBlobs_FailedDeleteReturnsError checks that prune returns an
+// error, so the command exits non-zero, when an unreferenced blob cannot
+// be deleted.
+func TestPruneBlobs_FailedDeleteReturnsError(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	env := newListEnv(t)
+
+	// The store holds no manifest, so nothing references this blob.
+	addBlob(t, env.store.testStorer, testBlobHashA)
+
+	store := faultstore.New(env.store)
+	store.OnDelete = refuseBlobDeletes
+	env.v.Storage = store
+
+	err := env.v.PruneBlobs(&vaultik.PruneOptions{Force: true})
+
+	require.ErrorContains(t, err, "1 blob(s) could not be deleted")
+}
+
+// TestPruneBlobs_JSONFailedDeleteReturnsError checks that prune --json
+// prints its document and then returns an error when an unreferenced
+// blob cannot be deleted.
+func TestPruneBlobs_JSONFailedDeleteReturnsError(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	env := newListEnv(t)
+	addBlob(t, env.store.testStorer, testBlobHashA)
+
+	store := faultstore.New(env.store)
+	store.OnDelete = refuseBlobDeletes
+	env.v.Storage = store
+
+	err := env.v.PruneBlobs(&vaultik.PruneOptions{JSON: true})
+
+	require.Error(t, err, "prune must fail when a blob cannot be deleted")
+
+	var result vaultik.PruneBlobsResult
+
+	require.NoError(t, json.Unmarshal(env.stdout.Bytes(), &result),
+		"stdout must hold the JSON document, got:\n%s", env.stdout.String())
+	assert.Equal(t, 1, result.BlobsFailed)
+	assert.Equal(t, 0, result.BlobsDeleted)
+}
+
+// TestCreateSnapshotPrune_FailedBlobDeleteReturnsError checks that the
+// prune step of snapshot create --prune fails the run when an
+// unreferenced blob cannot be deleted.
+func TestCreateSnapshotPrune_FailedBlobDeleteReturnsError(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	ctx := context.Background()
+	storeDir := filepath.Join(t.TempDir(), "store")
+	v, _, _ := backUpToFileDestination(ctx, t, storeDir)
+
+	// No snapshot references this blob, so the prune step deletes it.
+	orphan := filepath.Join(storeDir, "blobs", testBlobHashA[:2],
+		testBlobHashA[2:4], testBlobHashA)
+	require.NoError(t, os.MkdirAll(filepath.Dir(orphan), 0o750))
+	require.NoError(t, os.WriteFile(orphan, []byte("orphan"), 0o600))
+
+	store := faultstore.New(v.Storage)
+	store.OnDelete = refuseBlobDeletes
+	v.Storage = store
+
+	err := v.CreateSnapshot(&vaultik.SnapshotCreateOptions{
+		Cron:  true,
+		Prune: true,
+	})
+
+	require.ErrorContains(t, err, "1 blob(s) could not be deleted")
+	assert.FileExists(t, orphan)
+}

internal/vaultik/remove_snapshot_test.go

@@ -476,7 +476,8 @@ func TestRemoveAllSnapshots_WithForce(t *testing.T) {
 	out := tv.Stdout.String()
 	assert.Contains(t, out, "Removed 2 snapshot(s)")
 	assert.Contains(t, out, "Removed snapshot metadata from remote storage")
-	assert.Contains(t, out, "vaultik prune")
+	// Remote nuke, the only caller, deletes the blobs next itself.
+	assert.NotContains(t, out, "vaultik prune")
 }
 
 func TestRemoveAllSnapshots_DryRun(t *testing.T) {

internal/vaultik/restore.go

@@ -103,11 +103,12 @@ type RestoreResult struct {
 	BlobsDownloaded int
 	BytesDownloaded int64
 	Duration        time.Duration
+	FilesFailed     int
+	FailedFiles     []string // Paths of files that failed to restore
 	// Verification results (only populated if Verify option is set)
-	FilesVerified int
-	BytesVerified int64
-	FilesFailed   int
-	FailedFiles   []string // Paths of files that failed verification
+	FilesVerified     int
+	BytesVerified     int64
+	VerifyFailedFiles []string // Paths of restored files that failed verification
 }
 
 // Restore restores files from a snapshot to the target directory
@@ -658,20 +659,34 @@ func (v *Vaultik) handleRestoreVerification(
 	opts *RestoreOptions,
 	result *RestoreResult,
 ) error {
-	err := v.verifyRestoredFiles(v.ctx, repos, files, opts.TargetDir, result)
+	// A file that failed to restore was not written and is already
+	// reported as such, so it is not verified.
+	failedToRestore := make(map[string]bool, len(result.FailedFiles))
+	for _, path := range result.FailedFiles {
+		failedToRestore[path] = true
+	}
+
+	restored := make([]*database.File, 0, len(files))
+	for _, file := range files {
+		if !failedToRestore[file.Path.String()] {
+			restored = append(restored, file)
+		}
+	}
+
+	err := v.verifyRestoredFiles(v.ctx, repos, restored, opts.TargetDir, result)
 	if err != nil {
 		return fmt.Errorf("verification failed: %w", err)
 	}
 
-	if result.FilesFailed > 0 {
+	if len(result.VerifyFailedFiles) > 0 {
 		v.UI.Errorf("Verification failed: %s files did not match expected checksums.",
-			v.UI.Count(result.FilesFailed))
+			v.UI.Count(len(result.VerifyFailedFiles)))
 
-		for _, path := range result.FailedFiles {
+		for _, path := range result.VerifyFailedFiles {
 			v.UI.Detailf("%s", v.UI.Path(path))
 		}
 
-		return fmt.Errorf("%d %w", result.FilesFailed, errFilesFailedVerify)
+		return fmt.Errorf("%d %w", len(result.VerifyFailedFiles), errFilesFailedVerify)
 	}
 
 	v.UI.Completef("Verified %s files (%s).",
@@ -702,6 +717,8 @@ func (v *Vaultik) downloadSnapshotDB(
 		return nil, "", fmt.Errorf("downloading %s: %w", dbKey, err)
 	}
 
+	reader = newCloseOnCancelReader(v.ctx, reader)
+
 	defer func() { _ = reader.Close() }()
 
 	// Decrypt and decompress straight from the storage stream, then stream
@@ -1431,8 +1448,8 @@ func (v *Vaultik) verifyRestoredFiles(
 		if err != nil {
 			log.Error("File verification failed", "path", file.Path, "error", err)
 
-			result.FilesFailed++
-			result.FailedFiles = append(result.FailedFiles, file.Path.String())
+			result.VerifyFailedFiles = append(
+				result.VerifyFailedFiles, file.Path.String())
 		}
 
 		bytesProcessed += file.Size
@@ -1448,7 +1465,7 @@ func (v *Vaultik) verifyRestoredFiles(
 	log.Info("Verification complete",
 		"files_verified", result.FilesVerified,
 		"bytes_verified", ubytes(result.BytesVerified),
-		"files_failed", result.FilesFailed,
+		"files_failed", len(result.VerifyFailedFiles),
 	)
 
 	return nil

internal/vaultik/restore_interrupt_test.go

@@ -207,30 +207,37 @@ func TestRestoreSkipErrorsCancelDuringBlobDownload(t *testing.T) {
 		"the cancel was reported as a failed file")
 }
 
-// stallingBlobStorer wraps a Storer so that every blob download hands
-// over the first half of the blob and then stalls, ignoring the context,
-// as a file:// blob on a hung USB stick or network share does. Only
-// closing the returned reader ends the stall.
-type stallingBlobStorer struct {
+// stallingStorer wraps a Storer so that each download of a key chosen by
+// stalls hands over the first half of the object and then stalls,
+// ignoring the context, as a file:// read on a hung USB stick or network
+// share does. Only closing the returned reader ends the stall.
+type stallingStorer struct {
 	storage.Storer
 
+	stalls  func(key string) bool
 	once    sync.Once
 	stalled chan struct{}
 }
 
-func newStallingBlobStorer(inner storage.Storer) *stallingBlobStorer {
-	return &stallingBlobStorer{Storer: inner, stalled: make(chan struct{})}
+func newStallingStorer(
+	inner storage.Storer, stalls func(key string) bool,
+) *stallingStorer {
+	return &stallingStorer{
+		Storer:  inner,
+		stalls:  stalls,
+		stalled: make(chan struct{}),
+	}
 }
 
-func (s *stallingBlobStorer) Get(
+func (s *stallingStorer) Get(
 	ctx context.Context, key string,
 ) (io.ReadCloser, error) {
 	rc, err := s.Storer.Get(ctx, key)
-	if err != nil || !strings.HasPrefix(key, "blobs/") {
+	if err != nil || !s.stalls(key) {
 		return rc, err
 	}
 
-	blob, err := io.ReadAll(rc)
+	object, err := io.ReadAll(rc)
 	_ = rc.Close()
 
 	if err != nil {
@@ -242,7 +249,7 @@ func (s *stallingBlobStorer) Get(
 	pr, pw := io.Pipe()
 
 	go func() {
-		_, _ = pw.Write(blob[:len(blob)/2])
+		_, _ = pw.Write(object[:len(object)/2])
 
 		s.once.Do(func() { close(s.stalled) })
 	}()
@@ -250,17 +257,26 @@ func (s *stallingBlobStorer) Get(
 	return pr, nil
 }
 
-// TestInterruptDuringStalledBlobReadCleansTempDir stops a restore and a
-// deep verify while a blob read is stalled on a source that ignores the
-// context. Stopping must end that read, so the operation unwinds and
-// removes its decrypted scratch files well within the shutdown timeout
-// (issue #325).
+// TestInterruptDuringStalledReadCleansTempDir stops a restore and a deep
+// verify while a read of a blob or of the snapshot database is stalled
+// on a source that ignores the context. Stopping must end that read, so
+// the operation unwinds and removes its decrypted scratch files well
+// within the shutdown timeout (issues #325 and #356).
 //
 // Not parallel: it points TMPDIR at a private directory (via t.Setenv)
 // so it can assert on exactly the scratch files the operation created.
-func TestInterruptDuringStalledBlobReadCleansTempDir(t *testing.T) {
+func TestInterruptDuringStalledReadCleansTempDir(t *testing.T) {
 	log.Initialize(log.Config{})
 
+	stalledReads := map[string]func(key string) bool{
+		"blob": func(key string) bool {
+			return strings.HasPrefix(key, "blobs/")
+		},
+		"snapshot database": func(key string) bool {
+			return strings.HasSuffix(key, "/db.zst.age")
+		},
+	}
+
 	operations := map[string]func(v *Vaultik, snapshotID, targetDir string) error{
 		"restore": func(v *Vaultik, snapshotID, targetDir string) error {
 			return v.Restore(&RestoreOptions{
@@ -273,52 +289,58 @@ func TestInterruptDuringStalledBlobReadCleansTempDir(t *testing.T) {
 		},
 	}
 
-	for name, op := range operations {
-		t.Run(name, func(t *testing.T) {
-			fs := afero.NewOsFs()
-			root := t.TempDir()
+	for readName, stalls := range stalledReads {
+		for opName, op := range operations {
+			t.Run(readName+" read during "+opName, func(t *testing.T) {
+				fs := afero.NewOsFs()
+				root := t.TempDir()
 
-			// Random content, so the blob stays large enough to stall
-			// part-way through its compressed, encrypted body.
-			cfg, storer, snapshotID, _ := backupOneFile(context.Background(),
-				t, fs, root, "a.bin", randomBytes(t, 256*1024), 0o644)
+				// Random content, so the blob stays large enough to stall
+				// part-way through its compressed, encrypted body.
+				cfg, storer, snapshotID, _ := backupOneFile(context.Background(),
+					t, fs, root, "a.bin", randomBytes(t, 256*1024), 0o644)
 
-			scratch := filepath.Join(root, "scratch")
-			require.NoError(t, fs.MkdirAll(scratch, 0o755))
-			t.Setenv("TMPDIR", scratch)
+				scratch := filepath.Join(root, "scratch")
+				require.NoError(t, fs.MkdirAll(scratch, 0o755))
+				t.Setenv("TMPDIR", scratch)
 
-			stalling := newStallingBlobStorer(storer)
+				stalling := newStallingStorer(storer, stalls)
 
-			ctx, cancel := context.WithCancel(context.Background())
-			defer cancel()
+				ctx, cancel := context.WithCancel(context.Background())
+				defer cancel()
 
-			v := newRestoreVaultik(ctx, cfg, stalling, fs)
-			v.cancel = cancel
+				v := newRestoreVaultik(ctx, cfg, stalling, fs)
+				v.cancel = cancel
 
-			var opErr error
+				var opErr error
 
-			stop := v.StartOperation(func() {
-				opErr = op(v, snapshotID, filepath.Join(root, "restored"))
+				stop := v.StartOperation(func() {
+					opErr = op(v, snapshotID, filepath.Join(root, "restored"))
+				})
+
+				select {
+				case <-stalling.stalled:
+				case <-time.After(30 * time.Second):
+					t.Fatal("the operation never reached the stalled read")
+				}
+
+				// The snapshot database's temp directory is created just
+				// after its read starts, so it can appear after the stall.
+				require.Eventually(t, func() bool {
+					return len(scratchEntries(t, scratch)) > 0
+				}, 10*time.Second, 10*time.Millisecond,
+					"expected decrypted scratch files to exist mid-read")
+
+				stopCtx, stopCancel := context.WithTimeout(
+					context.Background(), 10*time.Second)
+				defer stopCancel()
+
+				require.True(t, stop(stopCtx),
+					"stop timed out; the stalled read was not interrupted")
+				require.ErrorIs(t, opErr, context.Canceled)
+				require.Empty(t, scratchEntries(t, scratch),
+					"decrypted scratch files remained after the interrupt")
 			})
-
-			select {
-			case <-stalling.stalled:
-			case <-time.After(30 * time.Second):
-				t.Fatal("the operation never reached a blob read")
-			}
-
-			require.NotEmpty(t, scratchEntries(t, scratch),
-				"expected decrypted scratch files to exist mid-read")
-
-			stopCtx, stopCancel := context.WithTimeout(
-				context.Background(), 10*time.Second)
-			defer stopCancel()
-
-			require.True(t, stop(stopCtx),
-				"stop timed out; the stalled blob read was not interrupted")
-			require.ErrorIs(t, opErr, context.Canceled)
-			require.Empty(t, scratchEntries(t, scratch),
-				"decrypted scratch files remained after the interrupt")
-		})
+		}
 	}
 }

internal/vaultik/restore_skip_errors_test.go

@@ -4,7 +4,9 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/spf13/afero"
@@ -104,6 +106,130 @@ func assertRestoreSkipsLostFiles(
 	}
 }
 
+// TestRestoreSkipErrorsVerifyChecksOnlyRestoredFiles restores with
+// SkipErrors and Verify after one blob of a two-blob snapshot was
+// deleted. Verification must check only the files that were written, so
+// a file of the deleted blob is reported as failed to restore and not
+// also as failing verification, and Restore must still return an error.
+func TestRestoreSkipErrorsVerifyChecksOnlyRestoredFiles(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	ctx := context.Background()
+	backup := backupThenDeleteOneBlob(ctx, t)
+
+	var out bytes.Buffer
+
+	v := newReaderVaultik(ctx, backup.cfg, backup.storer, nil, backup.fs)
+	v.UI = ui.NewWithColor(&out, false)
+
+	err := v.Restore(&vaultik.RestoreOptions{
+		SnapshotID: backup.snapshotID,
+		TargetDir:  backup.restoreDir,
+		Verify:     true,
+		SkipErrors: true,
+	})
+
+	require.Error(t, err, "restore must fail when files were skipped")
+	assert.Contains(t, err.Error(),
+		fmt.Sprintf("%d file(s) failed to restore", len(backup.lost)))
+
+	written := len(backup.files) - len(backup.lost)
+
+	assert.Contains(t, out.String(), fmt.Sprintf("Verifying %d files", written))
+	assert.Contains(t, out.String(), fmt.Sprintf("Verified %d files", written))
+	assert.NotContains(t, out.String(), "Verification failed")
+}
+
+// TestRestoreSkipErrorsVerifyReportsFailuresApart restores with
+// SkipErrors and Verify after one blob of a two-blob snapshot was
+// deleted, while one file that does restore is written one byte too long.
+// The restore warning must list only the files of the deleted blob, the
+// verification summary only the long file, each path once, and Restore
+// must return an error.
+func TestRestoreSkipErrorsVerifyReportsFailuresApart(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	ctx := context.Background()
+	backup := backupThenDeleteOneBlob(ctx, t)
+
+	var long string
+
+	for path := range backup.files {
+		if !backup.lost[path] {
+			long = path
+
+			break
+		}
+	}
+
+	var out bytes.Buffer
+
+	fs := trailingByteFs{Fs: backup.fs, suffix: long}
+	v := newReaderVaultik(ctx, backup.cfg, backup.storer, nil, fs)
+	v.UI = ui.NewWithColor(&out, false)
+
+	err := v.Restore(&vaultik.RestoreOptions{
+		SnapshotID: backup.snapshotID,
+		TargetDir:  backup.restoreDir,
+		Verify:     true,
+		SkipErrors: true,
+	})
+	require.Error(t, err, "restore must fail when files failed")
+
+	_, afterWarning, found := strings.Cut(out.String(),
+		fmt.Sprintf("%d file(s) failed to restore:", len(backup.lost)))
+	require.Truef(t, found, "no restore warning in:\n%s", out.String())
+
+	warning, summary, found := strings.Cut(afterWarning,
+		"Verification failed: 1 files did not match")
+	require.Truef(t, found, "no verification summary in:\n%s", out.String())
+
+	for path := range backup.lost {
+		assert.Equalf(t, 1, strings.Count(warning, path),
+			"%s must be listed once as failed to restore", path)
+		assert.NotContainsf(t, summary, path,
+			"%s was not restored and must not fail verification", path)
+	}
+
+	assert.NotContainsf(t, warning, long,
+		"%s was restored and must not be listed as failed to restore", long)
+	assert.Equalf(t, 1, strings.Count(summary, long),
+		"%s must be listed once as failing verification", long)
+}
+
+// trailingByteFs appends one byte, on close, to the file it opens whose
+// path ends in suffix, so that file is restored one byte too long and
+// fails verification.
+type trailingByteFs struct {
+	afero.Fs
+
+	suffix string
+}
+
+//nolint:ireturn // afero.Fs.OpenFile is defined to return the interface
+func (fs trailingByteFs) OpenFile(
+	name string, flag int, perm os.FileMode,
+) (afero.File, error) {
+	f, err := fs.Fs.OpenFile(name, flag, perm)
+	if err != nil || !strings.HasSuffix(name, fs.suffix) {
+		return f, err
+	}
+
+	return trailingByteFile{File: f}, nil
+}
+
+type trailingByteFile struct {
+	afero.File
+}
+
+func (f trailingByteFile) Close() error {
+	_, _ = f.Write([]byte{'x'})
+
+	return f.File.Close()
+}
+
 // TestRestoreMissingBlobAbortsWithoutSkipErrors checks that a deleted blob
 // still ends the restore with an error when SkipErrors is not set.
 func TestRestoreMissingBlobAbortsWithoutSkipErrors(t *testing.T) {

internal/vaultik/reused_blob_verify_test.go

@@ -0,0 +1,83 @@
+package vaultik_test
+
+import (
+	"context"
+	"io"
+	"path/filepath"
+	"testing"
+
+	"filippo.io/age"
+	"github.com/spf13/afero"
+	"github.com/stretchr/testify/require"
+	"sneak.berlin/go/vaultik/internal/log"
+	"sneak.berlin/go/vaultik/internal/ui"
+	"sneak.berlin/go/vaultik/internal/vaultik"
+)
+
+// TestVerifyPassesWhenBackupReusesStoredBlob backs up a file, then backs it
+// up again from an empty local index, as after `database delete`, with an
+// extra age recipient. The second backup builds the same blob, finds it
+// already stored and skips the upload, but its own copy is larger, because
+// age writes a header entry for each recipient. The second snapshot must
+// record the size of the stored object, so shallow and deep verify pass.
+func TestVerifyPassesWhenBackupReusesStoredBlob(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	fs := afero.NewOsFs()
+	tempDir := t.TempDir()
+
+	dataDir := filepath.Join(tempDir, "source")
+	storeDir := filepath.Join(tempDir, "remote")
+	secondDBPath := filepath.Join(tempDir, "second.sqlite")
+
+	chunkSize := int64(64 * 1024)
+	maxBlobSize := int64(512 * 1024)
+
+	require.NoError(t, fs.MkdirAll(dataDir, 0o755))
+	require.NoError(t, afero.WriteFile(fs,
+		filepath.Join(dataDir, "data.bin"),
+		bytesPattern("reuse-", int(chunkSize*3)), 0o644))
+
+	ctx := context.Background()
+
+	runFileStorageBackup(ctx, t, fs, dataDir, storeDir,
+		filepath.Join(tempDir, "first.sqlite"), chunkSize, maxBlobSize)
+
+	env := setupDedupBackupEnv(
+		ctx, t, fs, storeDir, secondDBPath, chunkSize, maxBlobSize)
+
+	defer func() { _ = env.db.Close() }()
+
+	extra, err := age.GenerateX25519Identity()
+	require.NoError(t, err)
+
+	env.cfg.AgeRecipients = append(env.cfg.AgeRecipients,
+		extra.Recipient().String())
+
+	snapshotID, result := runDedupSnapshot(ctx, t, env.sm, env.makeScanner(),
+		env.cfg.Hostname, "second", dataDir, secondDBPath)
+	require.Positive(t, result.BlobsCreated)
+	require.Zero(t, result.BlobsUploaded,
+		"the second backup should find every blob already stored")
+
+	require.NoError(t, env.db.Close())
+
+	verifier := &vaultik.Vaultik{
+		Config:  env.cfg,
+		Storage: env.storer,
+		Fs:      fs,
+		Stdout:  io.Discard,
+		Stderr:  io.Discard,
+		UI:      ui.NewWithColor(io.Discard, false),
+	}
+	verifier.SetContext(ctx)
+
+	require.NoError(t,
+		verifier.VerifySnapshotWithOptions(snapshotID, &vaultik.VerifyOptions{}),
+		"shallow verify should pass")
+	require.NoError(t,
+		verifier.VerifySnapshotWithOptions(snapshotID,
+			&vaultik.VerifyOptions{Deep: true}),
+		"deep verify should pass")
+}

internal/vaultik/snapshot.go

@@ -25,6 +25,7 @@ var (
 	errSnapshotVerifyFailed = errors.New("verification failed")
 	errRemoveAllNeedsForce  = errors.New("--all requires --force")
 	errSnapshotNotFound     = errors.New("snapshot not found")
+	errSnapshotRemoveFailed = errors.New("snapshot(s) could not be removed")
 	errInvalidTableName     = errors.New("invalid table name")
 	errNoAgeRecipients      = errors.New(
 		"creating a snapshot needs at least one public key in " +
@@ -242,12 +243,18 @@ func (v *Vaultik) createNamedSnapshot(
 		return err
 	}
 
+	previousSnapshotID, err := v.previousSnapshotID(snapName)
+	if err != nil {
+		return err
+	}
+
 	scanner := v.ScannerFactory(snapshot.ScannerParams{
-		EnableProgress: !opts.Cron,
-		UI:             v.UI,
-		Fs:             v.Fs,
-		Exclude:        v.Config.GetExcludes(snapName),
-		SkipErrors:     opts.SkipErrors,
+		EnableProgress:     !opts.Cron,
+		UI:                 v.UI,
+		Fs:                 v.Fs,
+		Exclude:            v.Config.GetExcludes(snapName),
+		SkipErrors:         opts.SkipErrors,
+		PreviousSnapshotID: previousSnapshotID,
 	})
 
 	snapshotID, err := v.SnapshotManager.CreateSnapshotWithName(
@@ -282,6 +289,24 @@ func (v *Vaultik) createNamedSnapshot(
 	return nil
 }
 
+// previousSnapshotID returns the ID of the most recent completed snapshot
+// named snapName in the local index, or "" when there is none.
+func (v *Vaultik) previousSnapshotID(snapName string) (string, error) {
+	snapshots, err := v.Repositories.Snapshots.ListRecent(v.ctx, listRecentLimit)
+	if err != nil {
+		return "", fmt.Errorf("listing snapshots: %w", err)
+	}
+
+	for _, s := range snapshots {
+		if s.CompletedAt != nil &&
+			parseSnapshotName(s.ID.String(), s.Hostname.String()) == snapName {
+			return s.ID.String(), nil
+		}
+	}
+
+	return "", nil
+}
+
 // resolveSnapshotPaths resolves source directories to absolute paths
 // with symlink resolution.
 func (v *Vaultik) resolveSnapshotPaths(snapName string) ([]string, error) {
@@ -1591,8 +1616,8 @@ func (v *Vaultik) handleRemoveAllDryRun(
 
 // executeRemoveAll deletes every local snapshot and, unless LocalOnly
 // is set, every corresponding remote metadata directory plus any
-// orphan remote keys. Blobs are not touched; the printed prune-command
-// hint is the next step.
+// orphan remote keys. Blobs are not touched. It returns an error when
+// any snapshot could not be removed.
 func (v *Vaultik) executeRemoveAll(
 	localSnaps, orphanRemoteKeys []string, opts *RemoveOptions,
 ) (*RemoveResult, error) {
@@ -1606,18 +1631,11 @@ func (v *Vaultik) executeRemoveAll(
 
 	result := &RemoveResult{}
 
-	remoteErrors := v.removeAllLocalSnapshots(localSnaps, opts, result)
+	failures := v.removeAllLocalSnapshots(localSnaps, opts, result)
 
 	if !opts.LocalOnly {
-		remoteErrors += v.removeAllOrphanRemotes(orphanRemoteKeys, result)
-
-		if remoteErrors == 0 {
-			result.RemoteRemoved = true
-		} else if v.UI != nil {
-			v.UI.Warningf("Some remote metadata deletions failed. Run '%s' "+
-				"once the remote is healthy to clean up unreferenced blobs.",
-				pruneCommandHint)
-		}
+		failures += v.removeAllOrphanRemotes(orphanRemoteKeys, result)
+		result.RemoteRemoved = failures == 0
 	}
 
 	if v.SnapshotManager != nil {
@@ -1627,6 +1645,10 @@ func (v *Vaultik) executeRemoveAll(
 		}
 	}
 
+	if failures > 0 {
+		return result, fmt.Errorf("%d %w", failures, errSnapshotRemoveFailed)
+	}
+
 	if opts.JSON {
 		return result, v.outputRemoveJSON(result)
 	}
@@ -1635,9 +1657,6 @@ func (v *Vaultik) executeRemoveAll(
 
 	if !opts.LocalOnly && result.RemoteRemoved {
 		v.printlnStdout("Removed snapshot metadata from remote storage")
-		v.stdoutf("\nNote: Removed snapshots' blobs remain on the remote. "+
-			"Run '%s' to delete any blobs no longer referenced by any "+
-			"remaining remote snapshot.\n", pruneCommandHint)
 	}
 
 	return result, nil
@@ -1680,12 +1699,13 @@ func (v *Vaultik) deleteIncompleteSnapshot(snapshotIDStr string, id any) bool {
 }
 
 // removeAllLocalSnapshots removes each known local snapshot (and, unless
-// --local-only, its remote metadata), returning the number of remote
-// deletion failures.
+// --local-only, its remote metadata), returning the number of snapshots
+// it could not remove. A snapshot left in the local index keeps its
+// remote metadata too, since it is not an orphan remote key.
 func (v *Vaultik) removeAllLocalSnapshots(
 	localSnaps []string, opts *RemoveOptions, result *RemoveResult,
 ) int {
-	remoteErrors := 0
+	failures := 0
 
 	for _, snapshotID := range localSnaps {
 		log.Info("Removing snapshot", "snapshot_id", snapshotID)
@@ -1695,6 +1715,8 @@ func (v *Vaultik) removeAllLocalSnapshots(
 			log.Error("Failed to remove from local database",
 				"snapshot_id", snapshotID, "error", err)
 
+			failures++
+
 			continue
 		}
 
@@ -1705,14 +1727,14 @@ func (v *Vaultik) removeAllLocalSnapshots(
 				log.Warn("Failed to remove snapshot metadata from remote",
 					"snapshot_id", snapshotID, "error", err)
 
-				remoteErrors++
+				failures++
 			}
 		}
 
 		result.SnapshotsRemoved = append(result.SnapshotsRemoved, snapshotID)
 	}
 
-	return remoteErrors
+	return failures
 }
 
 // removeAllOrphanRemotes deletes remote snapshot metadata that has no

internal/vaultik/snapshot_deleted_count_test.go

@@ -0,0 +1,196 @@
+package vaultik_test
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/spf13/afero"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"sneak.berlin/go/vaultik/internal/config"
+	"sneak.berlin/go/vaultik/internal/database"
+	"sneak.berlin/go/vaultik/internal/log"
+	"sneak.berlin/go/vaultik/internal/storage"
+	"sneak.berlin/go/vaultik/internal/ui"
+	"sneak.berlin/go/vaultik/internal/vaultik"
+)
+
+// These tests cover https://git.eeqj.de/sneak/vaultik/issues/304: a
+// backup counts a file as deleted only when the previous snapshot of
+// the same name had it and it is gone, and never counts an excluded
+// file.
+
+// deletedCountEnv is a backup setup over the source directory src whose
+// user-facing output is kept in out. Each test configures its snapshots
+// with setSnapshot.
+type deletedCountEnv struct {
+	v   *vaultik.Vaultik
+	out *bytes.Buffer
+	src string
+}
+
+// newDeletedCountEnv writes files, keyed by path relative to src.
+func newDeletedCountEnv(t *testing.T, files map[string][]byte) *deletedCountEnv {
+	t.Helper()
+
+	ctx := context.Background()
+	fs := afero.NewOsFs()
+	tempDir := t.TempDir()
+	srcDir := filepath.Join(tempDir, "src")
+
+	for rel, content := range files {
+		path := filepath.Join(srcDir, rel)
+		require.NoError(t, fs.MkdirAll(filepath.Dir(path), 0o755))
+		require.NoError(t, afero.WriteFile(fs, path, content, 0o644))
+	}
+
+	cfg := faultTestConfig()
+	cfg.IndexPath = filepath.Join(tempDir, "index.sqlite")
+	cfg.Snapshots = map[string]config.SnapshotConfig{}
+
+	store, err := storage.NewFileStorer(filepath.Join(tempDir, "remote"))
+	require.NoError(t, err)
+
+	db, err := database.New(ctx, cfg.IndexPath)
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = db.Close() })
+
+	repos := database.NewRepositories(db)
+	out := &bytes.Buffer{}
+	v := newBackupVaultik(ctx, cfg, store, repos, db, fs)
+	v.UI = ui.NewWithColor(out, false)
+
+	return &deletedCountEnv{v: v, out: out, src: srcDir}
+}
+
+// setSnapshot configures the snapshot name to back up the path rel
+// beneath src, with the given excludes.
+func (e *deletedCountEnv) setSnapshot(name, rel string, exclude ...string) {
+	e.v.Config.Snapshots[name] = config.SnapshotConfig{
+		Paths:   []string{filepath.Join(e.src, rel)},
+		Exclude: exclude,
+	}
+}
+
+// backUp runs a backup of the named snapshot and returns its output.
+func (e *deletedCountEnv) backUp(t *testing.T, name string) string {
+	t.Helper()
+
+	e.out.Reset()
+	require.NoError(t, e.v.CreateSnapshot(&vaultik.SnapshotCreateOptions{
+		Snapshots: []string{name},
+	}))
+
+	return e.out.String()
+}
+
+// A file this snapshot excludes is not counted as deleted: neither one
+// that another snapshot backs up, nor one that the previous snapshot of
+// this name had before the exclude was added.
+func TestBackupDoesNotCountExcludedFileAsDeleted(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	env := newDeletedCountEnv(t, map[string][]byte{
+		"top.txt":       []byte("top"),
+		"cache/tmp.bin": []byte("cache"),
+		"photos/a.jpg":  []byte("photo a"),
+		"photos/b.jpg":  []byte("photo b"),
+		"photos/c.jpg":  []byte("photo c"),
+	})
+	env.setSnapshot("photos", "photos")
+	env.setSnapshot("home", "", "/photos")
+
+	env.backUp(t, "photos")
+	assert.Contains(t, env.backUp(t, "home"), filesLine(2, 2, 0))
+
+	env.setSnapshot("home", "", "/photos", "/cache")
+	assert.Contains(t, env.backUp(t, "home"), filesLine(1, 0, 1))
+}
+
+// A file inside a directory that an exclude added after a backup
+// matches is not counted as deleted, though the pattern matches only the
+// directory.
+func TestBackupDoesNotCountFileInExcludedDirectoryAsDeleted(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	env := newDeletedCountEnv(t, map[string][]byte{
+		"top.txt":                         []byte("top"),
+		"user/.local/share/Trash/old.txt": []byte("old"),
+	})
+	env.setSnapshot("home", "")
+
+	assert.Contains(t, env.backUp(t, "home"), filesLine(2, 2, 0))
+
+	env.setSnapshot("home", "", "*/.local/share/Trash")
+	assert.Contains(t, env.backUp(t, "home"), filesLine(1, 0, 1))
+}
+
+// A backup counts only files that the previous snapshot of its own name
+// had, not one that a later snapshot of another name over the same path
+// had and that is since removed.
+func TestBackupIgnoresSnapshotOfAnotherName(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	env := newDeletedCountEnv(t, map[string][]byte{
+		"kept.txt": []byte("kept"),
+	})
+	env.setSnapshot("home", "")
+	env.setSnapshot("other", "")
+
+	env.backUp(t, "home")
+
+	// Snapshot start times are kept in whole seconds: wait so that other's
+	// snapshot is strictly the most recent.
+	time.Sleep(time.Second)
+
+	extra := filepath.Join(env.src, "extra.txt")
+	require.NoError(t, os.WriteFile(extra, []byte("extra"), 0o600))
+	env.backUp(t, "other")
+	require.NoError(t, os.Remove(extra))
+
+	assert.Contains(t, env.backUp(t, "home"), filesLine(1, 0, 1))
+}
+
+// A file removed from disk is counted as deleted by the next backup of
+// the snapshot that had it, and not by any later backup of that
+// snapshot, nor by the first backup of another name over the same path.
+func TestBackupCountsDeletedFileOnce(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	aContent := bytes.Repeat([]byte("a"), 1000)
+	bContent := bytes.Repeat([]byte("b"), 2000)
+	keptContent := bytes.Repeat([]byte("k"), 500)
+
+	env := newDeletedCountEnv(t, map[string][]byte{
+		"a.txt":    aContent,
+		"b.txt":    bContent,
+		"kept.txt": keptContent,
+	})
+	env.setSnapshot("home", "")
+	env.setSnapshot("other", "")
+
+	assert.Contains(t, env.backUp(t, "home"), filesLine(3, 3, 0))
+
+	require.NoError(t, os.Remove(filepath.Join(env.src, "a.txt")))
+	require.NoError(t, os.Remove(filepath.Join(env.src, "b.txt")))
+
+	summary := env.backUp(t, "home")
+	assert.Contains(t, summary,
+		"Files: 1 examined, 0 backed up, 1 unchanged, 2 deleted.")
+	assert.Contains(t, summary,
+		fmt.Sprintf("Data: %s total (%s backed up), %s deleted.",
+			env.v.UI.Size(int64(len(keptContent))), env.v.UI.Size(0),
+			env.v.UI.Size(int64(len(aContent)+len(bContent)))))
+
+	assert.Contains(t, env.backUp(t, "home"), filesLine(1, 0, 1))
+	assert.Contains(t, env.backUp(t, "other"), filesLine(1, 0, 1))
+}

internal/vaultik/verify.go

@@ -260,6 +260,8 @@ func (v *Vaultik) downloadVerifiedSnapshotDB(
 			fmt.Errorf("failed to download database: %w", err))
 	}
 
+	dbReader = newCloseOnCancelReader(v.ctx, dbReader)
+
 	defer func() { _ = dbReader.Close() }()
 
 	tdb, err := v.decryptAndLoadDatabase(dbReader, identities)