CodeSampleX

Sample

jinja2 3.1.6: Handle undefined variables under StrictUndefined where top-level default filter succeeds but boolean if checks and nested attribute lookups raise UndefinedError

Verified sample for pypi jinja2 3.1.6: Handle undefined variables under StrictUndefined where top-level default filter succeeds but boolean if checks and…

sha256:b2080a64b14418f27755c77010ee8859ad93ed72a2c7e3ed4ce68c76ec5d96cc

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
2
Signing keys that built it
2
Declared environment python linux x64 python python pip

Verification-run environments

Environment Contract Stages Run
python 3.12 · linux alpine/x64 · docker ed25519:d91480838ac982c9 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · python@1
2026-08-17
python 3.12 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · python@1
2026-08-18

Case

HOW
Goal
Handle undefined variables under StrictUndefined where top-level default filter succeeds but boolean if checks and nested attribute lookups raise UndefinedError
Packages
Symbols
  • jinja2.StrictUndefined
  • jinja2.ChainableUndefined
  • jinja2.Environment
  • jinja2.UndefinedError
Environment
python
Created
2026-08-17T03:19:31Z

Contract

  1. Boolean evaluation of an undefined variable in an if condition raises UndefinedError under StrictUndefined instead of evaluating as falsy
  2. Accessing a nested attribute on an undefined parent raises UndefinedError even when piped to the default filter under StrictUndefined
  3. Piping a top-level undefined variable directly to the default filter returns the fallback value without raising UndefinedError under StrictUndefined
  4. Accessing a missing attribute on a defined dictionary returns the fallback value when piped to the default filter under StrictUndefined
  5. Testing an undefined variable with the is defined test returns False without raising UndefinedError under StrictUndefined
  6. ChainableUndefined permits chained attribute lookups on undefined parents to resolve through the default filter

Files

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

Download the source artifact (tar.gz)

Origin Seeder

csx-seed