build method

Implementation

@override
FutureOr<void> build(BuildStep buildStep) async {
  final YamlMap pubspec = loadYaml(File('pubspec.yaml').readAsStringSync());
  final outputId = AssetId(buildStep.inputId.package, 'lib/pubspec.g.dart');

  final StringBuffer buffer = StringBuffer(
    'class Pubspec {\n'
    '  static const String name = \'${pubspec['name']}\';\n'
    '  static const String version = \'${pubspec['version']}\';\n',
  );

  final ProcessResult git = await Process.run('git', [
    'describe',
    '--tags',
    '--abbrev=0',
    '--dirty',
    '--match',
    'v*',
  ]);
  final ProcessResult rev = await Process.run('git', [
    'rev-list',
    'HEAD',
    '--count',
  ]);

  if (git.exitCode == 0 && rev.exitCode == 0) {
    String ref = git.stdout.toString();
    String count = rev.stdout.toString();

    // Strip the first `v` of the tag.
    if (ref.startsWith('v')) {
      ref = ref.substring(1);
    }

    // Strip the trailing `\n`.
    if (ref.endsWith('\n')) {
      ref = ref.substring(0, ref.length - 1);
    }
    if (count.endsWith('\n')) {
      count = count.substring(0, count.length - 1);
    }

    buffer.write('  static const String ref = \'$ref+$count\';\n');

    // ignore: avoid_print
    print('[PubspecBuilder] `Pubspec.ref` field is set to be `$ref+$count`.');
  } else {
    throw Exception(
      '[PubspecBuilder] Unable to properly generate `pubspec.g.dart` summary: `git` executable exited with code ${git.exitCode}, \nstdout: ${git.stdout}\nstderr: ${git.stderr}',
    );
  }

  buffer.write('}\n');

  await buildStep.writeAsString(outputId, buffer.toString());
}