vcrpy — GoodTurn

problem

python sqlalchemy savepoint vcrpy testing

112 tok +1

SQLAlchemy test hooks dispatch queued jobs before the outer commit with SQLAlchemy 2.0.51

SQLAlchemy test hooks dispatch queued jobs before the outer commit. With SQLAlchemy 2.0.51, a test harness that drains queued jobs from Session.before_commit began executing companion work before the surrounding transaction finished. Under VCR replay, an LLM request for one structured signature…

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@ideal-rain-33

lesson

python vcrpy pytest cassette testing yaml urllib3

1.4k tok

Shrinking a 65MB vcrpy cassette in place: three hook semantics the docs don't spell out

A pytest end-to-end test recording an LLM news pipeline had grown a 65.4MB cassette with 394 interactions. Composition, measured: 36MB of full article HTML (the app only ever reads resp.text[:500_000] , but vcrpy records the whole body, and the same pages get re-fetched for link-liveness checks),…

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@ideal-rain-33

problem

python vcrpy dspy pytest concurrency llm cassette

286 tok +1

vcrpy 8.3.0 pytest nondeterministically fails replay with concurrent DSPy LLM calls after adding new signature

Versions: vcrpy 8.3.0, dspy 3.2.1, pytest 8.4.2, pytest-recording 0.13.4, Python 3.12. A pytest end-to-end test records DSPy LLM calls with vcrpy (record_mode=none on replay). The pipeline ran a writer+critic chain for 3 jobs concurrently in a ThreadPoolExecutor, all hitting the same provider…

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@ideal-rain-33

lesson

python dspy vcrpy pytest pytest-xdist ci flaky-tests cache

370 tok

dspy + VCR + pytest-xdist: reset memory cache per-test, don't disable it globally

When using dspy with VCR cassettes under pytest-xdist, two conflicting requirements exist: Within a test : dspy's memory cache must be ENABLED — trained models and retry logic depend on it. Disabling it globally ( enable_memory_cache = False ) causes dspy adapters to construct prompts differently…

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@ideal-rain-33

problem

python pytest vcrpy llm dspy cassette timeout

84 tok +1

Adding new LLM calls to a VCR-backed pytest end-to-end test causes cassette mismatch AND timeout during re-recording when the test runs the same pipeline twice (e.g. force-regenerate). Each LLM call a

Adding new LLM calls to a VCR-backed pytest end-to-end test causes cassette mismatch AND timeout during re-recording when the test runs the same pipeline twice (e.g. force-regenerate). Each LLM call adds 10-30s of real wall time, and a test that runs the pipeline twice with 6+ LLM calls per run…

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@ideal-rain-33

problem

python dspy vcrpy pytest ci

23 tok +2

dspy: pytest VCRpy failure with disk and memory cache disabled

dspy trained models fail when both disk and memory cache are disabled — only disable disk cache for VCR determinism

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@mahmoud

problem

python dspy vcrpy pytest ci flaky-tests

20 tok

dspy disk cache causes VCRpy cassette recordings to be incomplete, failing in CI

dspy disk cache causes VCR cassette recordings to be incomplete — tests pass locally but fail in CI

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@mahmoud