3

我在颤振项目中使用easy_localization。我需要编写一些小部件测试。

但是看起来当.json带有翻译的文件太大时,MaterialApp永远不会构建它child,因此我无法测试我的小部件。

这是我的小型可重现项目的架构:

my_project
 |- assets
 |   |- lang
 |   |   |- ru.json
 |   |   |- sv.json
 |- test
 |   |- test_test.dart

这是我的test_test.dart文件:

import 'package:easy_localization/easy_localization.dart';
import 'package:easy_logger/easy_logger.dart';
import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:shared_preferences/shared_preferences.dart';

void main() {
  testWidgets('', (tester) async {
    await tester.runAsync(() async {
      SharedPreferences.setMockInitialValues({});
      EasyLocalization.logger.enableLevels = <LevelMessages>[
        LevelMessages.error,
        LevelMessages.warning,
      ];
      await EasyLocalization.ensureInitialized();
      await tester.pumpWidget(
        EasyLocalization(
          supportedLocales: const [Locale('sv')],  // <- Change it to 'ru' and it doesn't work
          path: 'assets/lang',
          child: Builder(
            builder: (context) {
              print('builder1');
              return MaterialApp(
                locale: EasyLocalization.of(context).locale,
                supportedLocales: EasyLocalization.of(context).supportedLocales,
                localizationsDelegates: EasyLocalization.of(context).delegates,
                home: Builder(
                  builder: (context) {
                    print('builder2');
                    return const SizedBox.shrink();
                  },
                ),
              );
            },
          ),
        ),
      );
      await tester.pumpAndSettle();
    });
  });
}

sv.json(一个小文件):

{
  "0": "0"
}

ru.json(一个大文件):

{
  "0": "0 - xx ... xx",  // <- 1000 "x"
  "1": "1 - xx ... xx",  // <- 1000 "x"
  // ...
  "3998": "3998 - xx ... xx",  // <- 1000 "x"
  "3999": "3999 - xx ... xx"  // <- 1000 "x"
}

在我的测试中,我有 2 个print应该分别打印builder1builder2.

当我Locale('sv')在测试中使用时,这很有效:

00:02 +0:                                                                                                                                                                                                                                               
builder1
builder2
00:02 +1: All tests passed!

但是当我使用Locale('ru'),MaterialApp不会建立它的孩子并且我没有得到打印builder2

00:03 +0:                                                                                                                                                                                                                                               
builder1
00:03 +1: All tests passed!

我怎样才能解决这个问题?

4

3 回答 3

2

这是因为 json 语言文件的加载方式。
看看这个:

// from flutter/lib/src/services/asset_bundle.dart

Future<String> loadString(String key, { bool cache = true }) async {
    final ByteData data = await load(key);
    // Note: data has a non-nullable type, but might be null when running with
    // weak checking, so we need to null check it anyway (and ignore the warning
    // that the null-handling logic is dead code).
    if (data == null)
      throw FlutterError('Unable to load asset: $key'); // ignore: dead_code
    // 50 KB of data should take 2-3 ms to parse on a Moto G4, and about 400 μs
    // on a Pixel 4.
    if (data.lengthInBytes < 50 * 1024) {
      return utf8.decode(data.buffer.asUint8List());
    }
    // For strings larger than 50 KB, run the computation in an isolate to
    // avoid causing main thread jank.
    return compute(_utf8decode, data, debugLabel: 'UTF8 decode for "$key"');
}

如果文件大于一定大小,Flutter 会使用compute它来加载它并避免 UI 卡顿。

如果在您的测试中,您在 之前添加此行await tester.pumpAndSettle(),这将暂停主线程,给隔离完成并恢复执行一些时间。

await Future.delayed(const Duration(milliseconds: 150), () {}); // this line
await tester.pumpAndSettle()

在我的笔记本电脑上,150 毫秒是持续通过测试的最短时间。

于 2021-07-24T16:24:53.587 回答
1

最后,我通过添加一个文件来修复它test/flutter_test_config.dart。我从这个问题中得到了灵感。

import 'dart:async';
import 'dart:convert';
import 'dart:io';
import 'package:easy_localization/src/localization.dart';
import 'package:easy_localization/src/translations.dart';
import 'package:flutter/widgets.dart';

Future<void> testExecutable(FutureOr<void> Function() testMain) async {
  final content = await File('assets/lang/sv.json').readAsString(); // <- Or `ru.json`
  final data = jsonDecode(content) as Map<String, dynamic>;

  // easy_localization works with a singleton instance internally. We abuse
  // this fact in tests and just let it load the English translations.
  // Therefore we don't need to deal with any wrapper widgets and
  // waiting/pumping in our widget tests.
  Localization.load(
    const Locale('en'),
    translations: Translations(data),
  );


  await testMain();
}
于 2021-08-18T15:07:14.307 回答
0

当您使用 CodegenLoader 时,这是一个小方法,您可以使用它来设置简单的本地化单例,类似于 Valentin Vignal 的 json 示例,我还建议使用不带回调参数的小函数而不是嵌套设置函数,至少如果你不在回调本身上操作。通过这种方式,很明显(只有!)副作用正在发生。

void addLocalization() {
  Localization.load(
    const Locale('en'),
    translations: Translations(CodegenLoader.en),
  );
}
于 2022-01-03T16:43:13.820 回答