compute method

@override Future<void> compute(ChangeBuilder builder)

Computes the changes for this producer using builder.

This method should not modify fixKind.

Implementation

@override
Future<void> compute(ChangeBuilder builder) async {
  final ClassDeclaration? classDecl = node
      .thisOrAncestorOfType<ClassDeclaration>();
  if (classDecl == null) return;

  final ClassElement? classEl = classDecl.declaredFragment?.element;
  if (classEl == null) return;

  // если dispose уже есть — не предлагаем
  final bool hasDispose = classDecl.getMethod('dispose') != null;
  if (hasDispose) return;

  final List<String> fields = _fieldsNeedingDispose(
    classEl,
    classDecl,
  ).toList()..sort();
  if (fields.isEmpty) return;

  // куда вставлять: перед build(), иначе перед закрывающей скобкой класса
  final MethodDeclaration? buildMethod = classDecl.getMethod('build');

  final int insertOffset =
      buildMethod?.offset ?? classDecl.classRightBracket.offset;

  final StringBuffer buffer = StringBuffer()
    ..writeln()
    ..writeln('  @override')
    ..writeln('  void dispose() {');
  for (final String f in fields) {
    buffer.writeln('    $f.dispose();');
  }
  buffer
    ..writeln('    super.dispose();')
    ..writeln('  }')
    ..writeln();

  await builder.addDartFileEdit(file, (DartFileEditBuilder edit) {
    edit.addSimpleInsertion(insertOffset, buffer.toString());
    try {
      edit.format(classDecl.sourceRange);
    } catch (_) {}
  });
}