private Stream<String> envVarNames(final OptionSpec spec) {
    return Arrays.stream(spec.names())
        .filter(name -> name.startsWith("--")) // Only long options are allowed
        .flatMap(
            name ->
                Stream.of(ENV_VAR_PREFIX, LEGACY_ENV_VAR_PREFIX)
                    .map(prefix -> prefix + nameToEnvVarSuffix(name)));
  }
Instantiates a new Environment variable default provider.

@param environment the environment
app/src/main/java/org/hyperledger/besu/cli/util/EnvironmentVariableDefaultProvider.java