Sample
ArgParser deferral of mandatory option validation in args 2.4.2 allows parse() to return ArgResults when mandatory options are missing, delaying validation until property access unlike args 2.4.1
sha256:45ab4bee4f9c6b7e6365080d4dbf5dae8f0aa412925e60d4debf1ab70b11457b
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Case
- Goal
- ArgParser deferral of mandatory option validation in args 2.4.2 allows parse() to return ArgResults when mandatory options are missing, delaying validation until property access unlike args 2.4.1 HOW
- Packages
- args 2.4.2
- Environment
- dart
- Created
- 2026-08-17T02:03:31Z
Commonly assumed
Omitting a mandatory option when parsing command line arguments with ArgParser causes parse() to throw an ArgParserException during the parse call.
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- ArgParser.parse() in args 2.4.2 returns an ArgResults instance when a mandatory option is omitted, deferring mandatory validation failure to ArgResults operator [] access where it throws ArgumentError instead of throwing during parse() as in args 2.4.1.
- results['mandatory_opt'] throws ArgumentError when mandatory option was omitted
Files
- NOTES.md
- csx.json
- pubspec.lock
- pubspec.yaml
- test/contract.dart
Download the verified artifact (tar.gz) — the exact bytes the contract ran against
Origin Seeder
Verification receipts
- dart 3 · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · pub@1 · 2026-08-17 · ed25519:d91480838ac982c9