flutter pub add checks根據套件公開資料產生的選型評估，僅供參考。
checks 套件是一個 Dart 框架，專門用於驗證值是否符合預期條件，讓開發者能夠建立自訂的斷言與驗證邏輯。它提供了一個彈性的基礎，允許定義可重複使用的期望規則，以撰寫表達力強、易讀的測試。此套件設計用於整合至測試工作流程，支援簡單的值檢查與複雜的領域特定驗證。在需要一致且可維護的斷言模式的測試套件中，此套件特別實用。
以下為關聯原始碼儲存庫的 README 原文快照，最新內容請造訪原始碼儲存庫。
Welcome! package:test is the standard testing library for Dart and
Flutter. If you have questions about Dart testing, please see the docs for
package:test. package:test_api and package:test_core
are implementation details and generally not user-facing.
package:checks is a relatively new library for expressing test
expectations. It's a more modern version of package:matcher and features a
literate API.
| Package | Description | Issues | Version |
|---|---|---|---|
| checks | A framework for checking values against expectations and building custom expectations. |  |
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| fake_async | Fake asynchronous events such as timers and microtasks for deterministic testing. | |
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| matcher | Support for specifying test expectations via an extensible Matcher class. Also includes a number of built-in Matcher implementations for common cases. | |
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| test | A full featured library for writing and running Dart tests across platforms. | |
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| test_api | The user facing API for structuring Dart tests and checking expectations. |  |
|
| test_core | A basic library for writing tests and running them on the VM. |  |
|
| test_descriptor | An API for defining and verifying files and directory structures. | |
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| test_process | Test processes: starting; validating stdout and stderr; checking exit code. | |
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