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Ejemplo

collection 1.19.1: Compare two Dart Lists, Maps or Sets by their contents, and use one as a cache key, when == on a collection is identity

Muestra verificada para pub collection 1.19.1: Compare two Dart Lists, Maps or Sets by their contents, and use one as a cache key, when == on a collection is…

sha256:7227421d006842fac6a96b0d2190f4a93f7cbbd5a2ee8a34116cb7c2f7b20d1c

Esta red ofrece una sola cosa: una muestra que compila. La ejecutó en un sandbox y guardó el recibo firmado. No califica ni garantiza nada: si el mismo código compila donde estás no es algo que haya medido. Cuántas claves de firma distintas presentaron un recibo de contrato aprobado. Una es solo el autor; más de una significa que alguien más también lo compiló. Una clave se genera sola y no tiene identidad registrada detrás, así que cuenta claves, no personas. MIT-0

Evidencia de ejecución

El entorno declarado y las ejecuciones firmadas se muestran por separado, para que veas exactamente qué ejecutó esta muestra y dónde.

Base de evidencia
Contrato firmado aprobado
Recibos de verificación
2
Claves de firma que lo compilaron
2
Entorno declarado dart 3 linux x64 dart 3 dart pub

Entornos de las ejecuciones de verificación

Entorno Contrato Etapas Ejecución
dart 3 · linux alpine/x64 · docker ed25519:a2ec939a4c60e243 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · pub@1
2026-08-14
dart 3 · linux debian/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · pub@1
2026-08-18

Caso

HOW
Objetivo
Compare two Dart Lists, Maps or Sets by their contents, and use one as a cache key, when == on a collection is identity
Paquetes
Símbolos
  • ListEquality
  • MapEquality
  • SetEquality
  • IterableEquality
  • DeepCollectionEquality
  • DeepCollectionEquality.unordered
  • DeepCollectionEquality.hash
  • groupBy
  • firstWhereOrNull
  • whereNotNull
  • HashMap
Entorno
dart 3
Creado
2026-08-14T13:05:28Z

Contrato

  1. assert two Lists with the same contents are not ==, and neither are two Maps nor two Sets, while package:test's equals matcher deep-compares the same values, nested ones included, and passes
  2. assert a const collection is canonicalized, so const [1, 2] is identical to const [1, 2], that canonicalization is per type argument, and that copying the list loses the equality again
  3. assert ListEquality compares in order while MapEquality and SetEquality do not, their hashes agree where their equals does, and IterableEquality compares a List against a Set
  4. assert ListEquality and MapEquality go exactly one level deep, so nested collections are compared with == and only match when the inner values are const-canonicalized
  5. assert DeepCollectionEquality recurses through nested maps, lists and sets, is already order-insensitive for Sets but not for Lists, that unordered() extends that to Lists as a multiset, and that non-collections fall through to the base equality
  6. assert a Map used as a key in a plain Map only matches the instance it was stored under, so the cache grows and never hits, while a HashMap given DeepCollectionEquality's equals and hash matches a rebuilt key whatever order its literal was written in
  7. assert equal structures produce equal DeepCollectionEquality hashes, that the ordered and unordered hashes track their own equalities, and that a HashMap given equals without hashCode misses 2000 freshly built keys without calling the equals it was given even once
  8. assert groupBy returns exact groups keyed in first-occurrence order, firstWhereOrNull returns null where the SDK's firstWhere throws StateError, and whereNotNull yields the same List<int> as the SDK's nonNulls that deprecates it
  9. assert Dart records compare by value and work as Map keys, but a record holding a List is back to identity

Archivos

  • csx.json
  • lib/equality.dart
  • pubspec.lock
  • pubspec.yaml
  • test/contract_test.dart

Descargar el artefacto de código fuente (tar.gz)

Seeder de origen

anonymous