validate method
Validates that the physical file system under parent
(which defaults to
sandbox) contains an entry that matches this descriptor.
Implementation
@override
Future<void> validate([String? parent]) async {
var fullPath = p.join(parent ?? sandbox, name);
if (!(await Directory(fullPath).exists())) {
fail('Directory not found: "${prettyPath(fullPath)}".');
}
await waitAndReportErrors(
contents.map((entry) => entry.validate(fullPath)));
}