internal/data: extract HardlinkIndex from restorer

The HardlinkIndex is also used by `cmd_stats`, thus place it in a shared
package.

cmd/restic/cmd_stats.go

@@ -13,7 +13,6 @@ import (
 	"github.com/restic/restic/internal/global"
 	"github.com/restic/restic/internal/repository"
 	"github.com/restic/restic/internal/restic"
-	"github.com/restic/restic/internal/restorer"
 	"github.com/restic/restic/internal/ui"
 	"github.com/restic/restic/internal/ui/progress"
 	statsui "github.com/restic/restic/internal/ui/stats"
@@ -228,7 +227,7 @@ func statsWalkSnapshot(ctx context.Context, snapshot *data.Snapshot, repo restic
 		return data.FindUsedBlobs(ctx, repo, restic.IDs{*snapshot.Tree}, stats.blobs, restic.NoopCounter)
 	}
 
-	hardLinkIndex := restorer.NewHardlinkIndex[struct{}]()
+	hardLinkIndex := data.NewHardlinkIndex[struct{}]()
 	err := walker.Walk(ctx, repo, *snapshot.Tree, walker.WalkVisitor{
 		ProcessNode: statsWalkTree(repo, opts, stats, hardLinkIndex, sp),
 	})
@@ -239,7 +238,7 @@ func statsWalkSnapshot(ctx context.Context, snapshot *data.Snapshot, repo restic
 	return nil
 }
 
-func statsWalkTree(repo restic.Loader, opts StatsOptions, stats *statsContainer, hardLinkIndex *restorer.HardlinkIndex[struct{}], progress *statsui.Progress) walker.WalkFunc {
+func statsWalkTree(repo restic.Loader, opts StatsOptions, stats *statsContainer, hardLinkIndex *data.HardlinkIndex[struct{}], progress *statsui.Progress) walker.WalkFunc {
 	return func(parentTreeID restic.ID, npath string, node *data.Node, nodeErr error) error {
 		if nodeErr != nil {
 			return nodeErr

internal/data/hardlinks_index.go

@@ -1,4 +1,4 @@
-package restorer
+package data
 
 import (
 	"sync"

internal/data/hardlinks_index_test.go

@@ -1,16 +1,16 @@
-package restorer_test
+package data_test
 
 import (
 	"testing"
 
-	"github.com/restic/restic/internal/restorer"
+	"github.com/restic/restic/internal/data"
 	rtest "github.com/restic/restic/internal/test"
 )
 
 // TestHardLinks contains various tests for HardlinkIndex.
 func TestHardLinks(t *testing.T) {
 
-	idx := restorer.NewHardlinkIndex[string]()
+	idx := data.NewHardlinkIndex[string]()
 
 	idx.Add(1, 2, "inode1-file1-on-device2")
 	idx.Add(2, 3, "inode2-file2-on-device3")

internal/restorer/restorer.go

@@ -360,7 +360,7 @@ func (res *Restorer) RestoreTo(ctx context.Context, dst string) (uint64, error)
 		}
 	}
 
-	idx := NewHardlinkIndex[string]()
+	idx := data.NewHardlinkIndex[string]()
 	filerestorer := newFileRestorer(dst, res.repo.LoadBlobsFromPack, res.repo.LookupBlob,
 		res.repo.Connections(), res.opts.Sparse, res.opts.Delete, res.repo.StartWarmup, res.opts.Progress)
 	filerestorer.Error = res.Error

internal/restorer/restorer_unix_test.go

@@ -4,7 +4,6 @@ package restorer
 
 import (
 	"context"
-	"github.com/restic/restic/internal/restic"
 	"io/fs"
 	"os"
 	"path/filepath"
@@ -13,8 +12,8 @@ import (
 	"time"
 
 	"github.com/restic/restic/internal/repository"
+	"github.com/restic/restic/internal/restic"
 	rtest "github.com/restic/restic/internal/test"
-	"github.com/restic/restic/internal/ui/progress"
 	restoreui "github.com/restic/restic/internal/ui/restore"
 )
 

internal/ui/restore/progress_test.go

@@ -1,13 +1,12 @@
 package restore
 
 import (
-	"github.com/restic/restic/internal/restic"
 	"testing"
 	"time"
 
 	"github.com/restic/restic/internal/errors"
+	"github.com/restic/restic/internal/restic"
 	"github.com/restic/restic/internal/test"
-	"github.com/restic/restic/internal/ui/progress"
 )
 
 type printerTraceEntry struct {