in lib/src/file_descriptor.dart [63:72]
Future<void> create([String? parent]) async {
// Create the stream before we call [File.openWrite] because it may fail
// fast (e.g. if this is a matcher file).
var file = File(p.join(parent ?? sandbox, name)).openWrite();
try {
await readAsBytes().listen(file.add).asFuture();
} finally {
await file.close();
}
}