Sample
Verify pytest.approx tolerance scaling around zero, boolean strictness, and structure restrictions
sha256:3cf69ad82bb42e948a1be82b3117d63fd8dd8997142061e59df15860347c883a
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Execution evidence
Declared environment and signed verification runs are separated so you can see exactly what this sample proves.
Evidence basisSigned contract pass
Verification receipts1
Verification levelL3_CONTRACT_PASS
Declared environment
- Execution context
- python
- Operating system
- linux
- Architecture
- x64
- Runtime
- python
- Language
- python
- Package manager
- pip
Verification-run environments
- Execution context
- python 3.12
- Operating system
- linux alpine · musl
- Architecture
- x64
- Runtime
- python 3.12
- Language
- python
- Package manager
- pip
- Execution
- container · docker
CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-17
Case
- Goal
- Verify pytest.approx tolerance scaling around zero, boolean strictness, and structure restrictions HOW
- Packages
-
pytest 9.0.3
- Environment
- python
- Created
- 2026-08-17T20:35:25Z
Commonly assumed
pytest.approx(0.0) matches small floating point numbers like 1e-7 using the default 1e-6 relative tolerance
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- pytest.approx(0.0) compares against zero using exclusively the absolute tolerance (defaulting to 1e-12) because relative tolerance scales to zero, causing 1e-7 == approx(0.0) to evaluate to False unless abs is explicitly set
- assert setting rel on approx(0.0) has no effect on zero comparisons while abs adjusts the allowable delta
- assert approx comparison against non-zero values uses relative tolerance scaled by the expected value
- assert approx rejects boolean-to-integer equality coercion returning False for 1 == approx(True)
- assert approx supports element-wise comparison between tuples and lists but rejects nested dictionaries and nested sequences with TypeError
- assert approx requires nan_ok=True to match float nan values
Files
- NOTES.md
- csx.json
- requirements.txt
- src/__init__.py
- src/comparator.py
- test/contract.py
Download the source artifact (tar.gz)
Origin Seeder
csx-seed
Verification receipts
- python 3.12 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-17 · ed25519:d91480838ac982c9