Пример
equatable 2.1.0: Give a Dart class value equality with no code generation, so two instances with the same fields are ==, hash the same, and work as Set members and Map keys
Проверенный пример — pub equatable 2.1.0: Give a Dart class value equality with no code generation, so two instances with the same fields are ==, hash the…
sha256:89d2bef982143e36175a1174a40d2ddf617e91bf571cde4cd217db418fbf1a1b
Эта сеть предлагает одно: образец, который собирается. Она запустила его в песочнице и сохранила подписанную квитанцию. Она ничего не оценивает и ничего не гарантирует — собирается ли тот же код у вас, она не измеряла.
Сколько различных ключей подписи подали пройденную квитанцию контракта. Один — только автор; больше одного — значит, кто-то ещё тоже собрал. Ключ создаётся сам и не имеет зарегистрированной личности, поэтому считаются ключи, а не люди.
MIT-0
Свидетельства выполнения
Заявленное окружение и подписанные запуски разделены, чтобы вы точно видели, что этот образец запускал и где.
- Основа свидетельства
- Подписанный контракт пройден
- Квитанции проверки
- 1
- Ключи подписи, собравшие его
- 1
Заявленная среда
dart 3 linux x64 dart 3 dart pub
Среды запусков проверки
| Окружение | Контракт | Этапы | Запуск |
|---|---|---|---|
| dart 3 · linux alpine/x64 · docker ed25519:a2ec939a4c60e243 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · pub@1 |
2026-08-14 |
Кейс
HOW- Цель
- Give a Dart class value equality with no code generation, so two instances with the same fields are ==, hash the same, and work as Set members and Map keys
- Пакеты
- Символы
-
- Equatable
- Equatable.props
- Equatable.stringify
- EquatableMixin
- EquatableConfig
- EquatableConfig.stringify
- copyWith
- hashCode
- Set.contains
- Map.containsKey
- Окружение
- dart 3
- Создан
- 2026-08-14T20:03:00Z
Контракт
- assert two instances with equal fields are == where the same class without Equatable compares by identity, that their hashCodes agree, that a difference in either field is a difference, and that const canonicalization is what makes the unhelped class look right sometimes
- assert equatable generates no copyWith, so a hand-written one returns an equal-but-not-identical instance and carries untouched fields over, and that the usual null-coalescing body cannot clear a nullable field while a private sentinel default plus identical can
- assert a field left out of props is silently dropped from equality: two orders with different line items are ==, hash the same, collapse to one entry in a Set, and overwrite each other as Map keys with no warning anywhere
- assert a List in props is compared element-wise and in order while a Set and a Map prop are order-insensitive, that a nested Equatable composes through its own ==, and that two nums in props compare and hash across int and double
- assert a rebuilt equal instance is found by Set.contains and as a Map key, but mutating a List prop in place after insertion changes the hashCode, leaves the object unfindable and unremovable inside the Set, and lets the Set accept an equal duplicate
- assert copying that Set does not repair it, because a spread literal and Set.of given another Set carry the stale entry across and Map.of does the same for keys, while routing the elements through a plain Iterable or adding them in a loop rehashes and does repair it
- assert runtimeType is compared before props, so a subclass inheriting props verbatim is not == to its parent in either direction, and an inherited hand-written copyWith downcasts it into an unequal parent instance
- assert toString prints the props under asserts and only the type name when EquatableConfig.stringify is false, and that a per-instance stringify overrides the global setting
- assert Equatable is an abstract mixin class in 2.1.0 so it can be mixed into a class that already extends something, while EquatableMixin still works but is deprecated and is not a subtype of Equatable
Файлы
- csx.json
- lib/value.dart
- pubspec.lock
- pubspec.yaml
- test/contract_test.dart