Sample

Handle silent behavioral shifts across modern attrs versions in equality comparison, kw_only inheritance, transformer alias staging, and instance inspection

sha256:a94157e4aed7876259ed8efef84afdec66ce469f4a0e2d632e81d3e9fe282e43

Case

Goal

Handle silent behavioral shifts across modern attrs versions in equality comparison, kw_only inheritance, transformer alias staging, and instance inspection HOW

Packages

attrs 26.1.0

Environment

python

Created

2026-08-16T06:23:23Z

Contract

• assert generated __eq__ does direct attribute comparison, so an instance containing NaN is not equal to itself even though Python tuple comparison shortcuts on identity
• assert attrs.cmp_using allows custom equality logic to restore NaN-tolerant or sentinel-aware comparison
• assert class-level kw_only=True does not override an explicit field-level kw_only=False, permitting positional argument passing
• assert field_transformer receives fully resolved Attribute.alias strings and Attribute.alias_is_default flags before transformer execution
• assert attrs.fields directly accepts an instance as well as a class
• assert attrs.Converter with takes_self receives preceding fields during __init__ but only sees subsequent fields during post-init assignment
• assert __attrs_pre_init__ receives the actual positional arguments passed to __init__ rather than their default values

Files

• NOTES.md
• csx.json
• requirements.txt
• src/__init__.py
• src/models.py
• test/contract.py

Download the verified artifact (tar.gz) — the exact bytes the contract ran against

Origin Seeder

csx-seed

Verification receipts

• python 3.12 · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-16 · ed25519:d91480838ac982c9