# 重置 TestTextInput 状态

> 测试之间，TestTextInput 的状态将重置。




:::important
These breaking change docs are accurate, as of the release
under which they are published. Over time, the
workarounds described here might become inaccurate.
We don't, in general, keep these breaking change docs up
to date as of each release.

这些破坏性改动文档的准确性仅限于其发布时对应的版本。
随着时间的推移，文档中描述的方案可能会逐渐失效。
通常情况下，我们不会在每次发布新版本时都对这些文档进行同步更新。

The [breaking change index file](/release/breaking-changes)
lists the docs created for each release.

[破坏性改动列表](/release/breaking-changes) 
列出了每个版本的文档。

:::


## Summary

## 概述

The state of a `TestTextInput` instance,
a stub for the system's onscreen keyboard,
is now reset between tests.

现在 `TestTextInput` 实例（系统屏幕键盘的存根）的状态会在测试之间重置。

## Context

## 上下文

The Flutter test framework uses a class called `TestTextInput`
to track and manipulate editing state in a widgets test.
Individual tests can make calls that modify the internal
state of this object, sometimes indirectly (such as
by setting their own handlers on `SystemChannels.textInput`).
Subsequent tests might then check the state of
`WidgetTester.testTextInput` and get unexpected values.

Flutter 测试框架中使用一个名为 `TestTextInput` 的类来跟踪和操作 widgets 测试中的编辑状态。
个别测试可以通过方法调用来修改此对象的内部状态，
有时是间接的（例如通过 `SystemChannels.textInput` 设置自己的处理程序）。
在其之后的的测试可能会检查 `WidgetTester.testTextInput` 的状态，拿到不符合预期的值。

## Description of change

## 更改描述

The state of `WidgetTester.testTextInput`
is now reset before running a `testWidgets` test.

现在 `WidgetTester.testTextInput` 的状态会在运行 `testWidgets` 测试之前重置。

## Migration guide

## 迁移指南

Tests that relied on dirty state from a previously run
test must be updated. For example, the following test,
from `packages/flutter/test/material/text_field_test.dart`
in the `'Controller can update server'` test,
previously passed because of a combination of dirty state
from previous tests and a failure to actually set state
in cases where it should have been set.

之前依赖于 `WidgetTester.testTextInput` 运行时脏状态的测试必须更新。
例如 `packages/flutter/test/material/text_field_test.dart`
文件中的 `'Controller can update server'` 测试。
在这之前，其它测试使得 `WidgetTester.testTextInput` 处于脏状态，
并且在应该设置状态的时候设置状态失败，所以它通过了测试。

Code before migration:

迁移前的代码：

In a `widgetsTest`, before actually changing text on a
text editing widget, this call might have succeeded:

`widgetsTest` 里，在实际更改文本编辑 widget 上的文本之前，
此调用可能已成功：

```dart
    expect(tester.testTextInput.editingState['text'], isEmpty);
```

Code after migration:

迁移后的代码：

Either remove the call entirely, or consider using the
following to assert that the state hasn't been modified yet:

要么完全删除该调用，要么考虑使用以下声明来确认状态尚未被修改：

```dart
    expect(tester.testTextInput.editingState, isNull);
```

## Timeline

## 时间轴

Landed in version: 1.16.3<br>
In stable release: 1.17

发布于版本：1.16.3<br>
发布于稳定版本：1.17

## References

## 参考文献

API documentation:

API 文档：

* [`TestTextInput`][]
* [`WidgetTester`][]

Relevant issue:

相关 issues：

* [Randomize test order to avoid global state][]

Relevant PR:

相关 PR：

* [Reset state between tests][]


[Randomize test order to avoid global state]: https://github.com/flutter/flutter/issues/47233
[Reset state between tests]: https://github.com/flutter/flutter/pull/47464
[`TestTextInput`]: https://api.flutter-io.cn/flutter/flutter_test/TestTextInput-class.html
[`WidgetTester`]: https://api.flutter-io.cn/flutter/flutter_test/WidgetTester-class.html