Quelltest 0.6.9 is out. It is a focused bug-fix release with no new features — just three root-cause fixes that were responsible for the majority of verified=0 results on real codebases.

What changed

1. Async functions are now skipped

The rule engine was attempting to generate tests for async def functions. This caused two problems: the generated test called the coroutine synchronously (so it always failed phase 1), and the violation injection could leave the source in a bad state before the async event loop was set up correctly.

The fix: the scanner now identifies async def at the AST level before dispatching to any rule. Async functions are logged as skipped (async) in report.json and never sent to the generator.

This was the root cause of verified=0 results on FastAPI backends where most route handlers are async.

# Previously attempted — caused false failures
async def create_payment(request: PaymentRequest) -> PaymentResponse:
    """Returns: PaymentResponse with transaction_id."""
    ...

# 0.6.9: skipped cleanly, logged in report.json

2. Pydantic classmethod stub deduplication

When a Pydantic model had both a field_validator and a model_validator, the stub generator was injecting the same @classmethod stub twice into the test file — once for each validator. This produced a SyntaxError on the second injection, which caused the entire test class to be rejected.

The deduplication pass now runs before injection. If a @classmethod stub already exists in the target test class, it is not added again.

3. Enum kwarg name fix

Field(default=Status.ACTIVE) was being read as Field(Status.ACTIVE) because the stub parser was looking for positional args only. Enum field defaults passed as keyword arguments were silently dropped, producing an incomplete ENUM_VALID constraint with no values.

The fix checks both args and keywords in the AST Call node for enum-typed defaults.

Why these three bugs

All three stem from the same underlying assumption: that functions in the codebase are synchronous, standalone, and use only positional arguments. FastAPI and Pydantic v2 break all three assumptions systematically.

Upgrading

pip install --upgrade quelltest
quell --version  # should print 0.6.9

No configuration changes needed. The report.json schema is unchanged — skipped (async) entries appear under the existing skipped key.

What's next

The roadmap for 0.7.x includes:

Async test generation using pytest-asyncio (opt-in via --async)
TypeScript type reader for zod schemas
Stryker mutation result ingestion (the mutation_reader stub)

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