import 'package:meta/meta.dart'; required in all source files.

[pauldemarco]

Since the generated file contains some annotations from the meta package, (@immutable, @required), this import statement is needed in all data class files:

import 'package:meta/meta.dart';
import 'package:auto_data/auto_data.dart';

Ideally there should only be the auto_data import statement:

import 'package:auto_data/auto_data.dart';