sha256 method
Lowercase hex SHA-256 of the file at path.
Implementation
@override
Future<String> sha256(String path) async {
hashed.add(path);
final fixed = hashes?[path];
if (fixed != null) return fixed;
final hashOf = this.hashOf;
if (hashOf != null) return hashOf(path);
return dartSha256(path);
}