lib/db: Fix prefixed walks (fixes #4925) (#4940)

lib/db/set_test.go

@@ -50,6 +50,15 @@ func globalList(s *db.FileSet) []protocol.FileInfo {
 	})
 	return fs
 }
+func globalListPrefixed(s *db.FileSet, prefix string) []db.FileInfoTruncated {
+	var fs []db.FileInfoTruncated
+	s.WithPrefixedGlobalTruncated(prefix, func(fi db.FileIntf) bool {
+		f := fi.(db.FileInfoTruncated)
+		fs = append(fs, f)
+		return true
+	})
+	return fs
+}
 
 func haveList(s *db.FileSet, n protocol.DeviceID) []protocol.FileInfo {
 	var fs []protocol.FileInfo
@@ -61,6 +70,16 @@ func haveList(s *db.FileSet, n protocol.DeviceID) []protocol.FileInfo {
 	return fs
 }
 
+func haveListPrefixed(s *db.FileSet, n protocol.DeviceID, prefix string) []db.FileInfoTruncated {
+	var fs []db.FileInfoTruncated
+	s.WithPrefixedHaveTruncated(n, prefix, func(fi db.FileIntf) bool {
+		f := fi.(db.FileInfoTruncated)
+		fs = append(fs, f)
+		return true
+	})
+	return fs
+}
+
 func needList(s *db.FileSet, n protocol.DeviceID) []protocol.FileInfo {
 	var fs []protocol.FileInfo
 	s.WithNeed(n, func(fi db.FileIntf) bool {
@@ -892,6 +911,32 @@ func TestWithHaveSequence(t *testing.T) {
 	})
 }
 
+func TestIssue4925(t *testing.T) {
+	ldb := db.OpenMemory()
+
+	folder := "test)"
+	s := db.NewFileSet(folder, fs.NewFilesystem(fs.FilesystemTypeBasic, "."), ldb)
+
+	localHave := fileList{
+		protocol.FileInfo{Name: "dir"},
+		protocol.FileInfo{Name: "dir.file"},
+		protocol.FileInfo{Name: "dir/file"},
+	}
+
+	replace(s, protocol.LocalDeviceID, localHave)
+
+	for _, prefix := range []string{"dir", "dir/"} {
+		pl := haveListPrefixed(s, protocol.LocalDeviceID, prefix)
+		if l := len(pl); l != 2 {
+			t.Errorf("Expected 2, got %v local items below %v", l, prefix)
+		}
+		pl = globalListPrefixed(s, prefix)
+		if l := len(pl); l != 2 {
+			t.Errorf("Expected 2, got %v global items below %v", l, prefix)
+		}
+	}
+}
+
 func replace(fs *db.FileSet, device protocol.DeviceID, files []protocol.FileInfo) {
 	fs.Drop(device)
 	fs.Update(device, files)