evaluate method

@override DVGateOutcome evaluate(DVReleaseGateContext context)

Implementation

@override
DVGateOutcome evaluate(DVReleaseGateContext context) {
  final int? locked = lock.current?.protocol;
  if (locked != context.candidate.protocolVersion) {
    return DVGateOutcome.hold(
      name,
      'the protocol lock is at ${locked ?? 'no version'} and release '
      '${context.candidate.id} records protocol '
      '${context.candidate.protocolVersion}; the window cannot be read for it',
      overridable: false,
    );
  }

  final DVReleaseRecord? previous = context.previous;
  final DVContractDecision decision = DVContractDecision.evaluate(
    windowed: window.served(lock, now: context.now),
    readsOldShape: (int protocol) => _readBy(protocol).isNotEmpty,
    replacing: previous == null
        ? null
        : (release: previous.id, builtFor: previous.schema[migration]),
  );
  final List<int> served = decision.windowed!;

  if (decision.readers.isNotEmpty) {
    const String code = 'DV-RELEASE-005';
    final List<String> readers = <String>[
      for (final int protocol in decision.readers)
        'protocol $protocol reads ${_readBy(protocol).join(', ')}',
    ];
    final String message =
        'contract of $migration refused: ${readers.join('; ')}, inside the '
        'window $served';
    _diagnose(code, message);
    return DVGateOutcome.hold(
      name,
      message,
      code: code,
      overridable: false,
      evidence: <String, Object?>{'served': served, 'readers': readers},
    );
  }

  if (decision.replacingReadsOldShape) {
    final DVContractReplacing replacing = decision.replacing!;
    return DVGateOutcome.hold(
      name,
      'contract of $migration refused: ${replacing.release}, the release '
      'being replaced, was built for '
      '${replacing.builtFor?.name ?? 'the shape before it'} and still reads '
      'what the contract drops',
      overridable: false,
    );
  }
  return DVGateOutcome.pass(
    name,
    evidence: <String, Object?>{'served': served},
  );
}