Ejemplo
args 2.7.0: Build and test a package:args CommandRunner subcommand CLI, telling apart which node reports a UsageException and pinning the option rules that differ from argparse, getopt and clap
Muestra verificada para pub args 2.7.0: Build and test a package:args CommandRunner subcommand CLI, telling apart which node reports a UsageException and…
sha256:d5e47381de03ab961e2135483018d410dd3e1365963e163f552519d3a16f7875
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
- 1
- Claves de firma que lo compilaron
- 1
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 |
Caso
HOW- Objetivo
- Build and test a package:args CommandRunner subcommand CLI, telling apart which node reports a UsageException and pinning the option rules that differ from argparse, getopt and clap
- Paquetes
- Símbolos
-
- CommandRunner
- CommandRunner.run
- Command.run
- Command.argResults
- Command.usageException
- UsageException
- ArgParser.addFlag
- ArgParser.addOption
- ArgParserException
- ArgResults.flag
- ArgResults.option
- ArgResults.rest
- Entorno
- dart 3
- Creado
- 2026-08-14T19:59:28Z
Contrato
- assert a subcommand runs and the value its run returns comes back out of CommandRunner<int>.run, so the exit code travels as a return value and nothing is printed
- assert no arguments, --help and <command> --help all complete with null after printing usage, so null is a success value and Command.run was never reached
- assert an unknown command is a UsageException whose usage is the runner's, with Global options and Available commands, whose toString is message and usage joined, and whose message gains an edit-distance suggestion block only within the default limit of 2
- assert a parse error inside a subcommand is the same UsageException type carrying that subcommand's usage instead of the command list, while a stray word before the command name is reported by the top-level parser and carries the runner's usage again
- assert a unique prefix of a long option is simply an unknown option, because long names are resolved by exact name or alias and no switch adds prefix matching, while the single-letter abbr and an exact alias both work and the alias stays out of the usage block
- assert a collapsed run of single letters takes its value on the FIRST letter, so -tprod sets the option and -vtprod and -vt prod both fail because a later letter must be a flag, and that an unknown letter has one message alone and a different one inside a run
- assert mandatory: true is enforced during parsing only when the option also declares a callback, and that without one the parse succeeds and leaves the option out of the results entirely
- assert the callback-less mandatory option therefore fails as an ArgumentError from ArgResults.option after the command body has already started, while the same declaration with a callback fails as a UsageException during parsing before run is reached
- assert the required option that behaves the same either way is a null check plus an explicit usageException call, throwing UsageException with that command's usage
- assert addFlag creates --no-x for free, including for a flag that already defaults to false, that negatable: false turns --no-x into an error naming the spelling that was typed rather than the declared flag, and that the usage block renders the difference as --[no-]x
- assert everything after -- lands in rest unparsed so a flag past it does not take effect, and that only the first -- is consumed
- assert a -- before the command name stops the top-level parser before it ever looks the command up, so the command that was asked for is reported as unknown while being suggested back
Archivos
- csx.json
- lib/cli.dart
- pubspec.lock
- pubspec.yaml
- test/contract_test.dart