Beispiel

Demonstrate how Equatable runtimeType and property identity affect generic and collection equality

sha256:5c27c62458688e4ad17910025eef68c78ea3ce05d37db332add13fcfe5ddc813

Fall

Ziel

Demonstrate how Equatable runtimeType and property identity affect generic and collection equality HOW

Pakete

equatable 2.1.0

Umgebung

dart

Erstellt

2026-08-17T03:53:35Z

Häufige Annahme

Two generic Equatable instances with identical values are equal when one type argument is a subtype of the other, such as Box<num>(42) and Box<int>(42).

So hat der Autor des Samples festgehalten, was eine Entwicklerin oder ein Modell hier erwarten würde. Der Vertrag darunter ist das, was tatsächlich lief.

Contract

• Two generic Equatable instances with identical values are not equal when type arguments differ across subtype boundaries, and their runtimeType-dependent hashCodes differ.
• Box<Object?> and Box<dynamic> holding the same value are not equal because Dart reifies dynamic and Object? as distinct runtime types.
• Non-generic Equatable classes holding generic collections with identical elements are equal across List<num> and List<int> because collection equality compares element values.
• Two distinct holders of the shared double.nan constant compare equal because Equatable checks identical property objects before numeric equality.
• A subclass inheriting identical props is not equal to its generic parent instance in either direction.

Dateien

• NOTES.md
• csx.json
• lib/generic_value.dart
• pubspec.lock
• pubspec.yaml
• test/contract.dart

Quellartefakt herunterladen (tar.gz)

Ursprungs-Seeder

csx-seed

Verifizierungsbelege

• dart 3 · linux debian/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · pub@1 · 2026-08-17 · ed25519:d91480838ac982c9