示例

Configure JsonSerializable options and enum decoding fallbacks in json_annotation, proving snake_case key enforcement, unknownEnumValue null bypass, and readValue error attribution

sha256:eabf9843a09e0a2fac2d9fe9f0df3eebd2f3eef2bf42bdd99120e6754d499267

案例

目标

Configure JsonSerializable options and enum decoding fallbacks in json_annotation, proving snake_case key enforcement, unknownEnumValue null bypass, and readValue error attribution HOW

包

json_annotation 4.9.0

环境

dart

创建时间

2026-08-17T14:38:30Z

常见的想当然

A model expects JsonSerializable.fromJson to accept camelCase Dart option names, unknownEnumValue to serve as a fallback when an enum field is null, and disallowNullValues to reject missing keys.

这是本样本作者记下的、开发者或模型在此处通常会有的预期。下面的契约才是真正运行过的东西。

契约

• JsonSerializable.fromJson enforces snake_case option keys and disallowUnrecognizedKeys, throwing a CheckedFromJsonException with badKey true on camelCase Dart property names
• field_rename configuration parses exact enum string identifiers and throws an ArgumentError wrapped in CheckedFromJsonException on non-matching strings like screaming_snake
• $enumDecodeNullable returns the unknownValue fallback for unrecognized wire strings but returns null when the input is null, while non-nullable $enumDecode throws ArgumentError on null inputs even when unknownValue is provided
• JsonKey.nullForUndefinedEnumValue causes $enumDecodeNullable to map unrecognized wire strings to null, but passing an incompatible enum type throws an ArgumentError
• readValue custom extractors allow retrieving values from nested paths or aliases, and type mismatch exceptions are re-attributed to the target model field key in CheckedFromJsonException
• $checkKeys evaluates allowedKeys first, requiredKeys second, and disallowNullValues last, where disallowNullValues ignores completely absent keys unless combined with requiredKeys
• $checkedNew attaches the failing key name to CheckedFromJsonException for missing and disallowed-null keys, but leaves key as null for UnrecognizedKeysException

文件

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

下载源代码构件 (tar.gz)

原始种子者

csx-seed

验证回执

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