Pydantic Drop support for pytest 7.4 (Fix)

The Fix

pip install pydantic==2.8.0

Based on closed pydantic/pydantic issue #9597 · PR/commit linked

Production note: Most teams hit this during upgrades or environment changes. Roll out with a canary and smoke critical endpoints (health, OpenAPI/docs) before 100%.

Open PR/Commit

@@ -5,7 +5,7 @@
 strategy = ["cross_platform"]
 lock_version = "4.4.1"
-content_hash = "sha256:43a40942d360a02d57d70536878cc45241924c0e8f7a08b429407b5b386b7ac5"
+content_hash = "sha256:a4bdad8895ac9a5f5d2b73bffdff1c66055ae99d72de6576fe9ad9dc20caf423"

fix.md

Option A — Upgrade to fixed release\npip install pydantic==2.8.0\nWhen NOT to use: Do not use if it changes public behavior or if the failure cannot be reproduced.\n\n

Why This Fix Works in Production

Trigger: - [ ] [Compatibility between releases](https://docs.pydantic.dev/changelog/)
Mechanism: The required version of pytest was not updated, causing compatibility issues
Why the fix works: Updates the required version of pytest to 8.x and asserts that all warnings emitted by pytest.warns() are expected, addressing compatibility issues. (first fixed release: 2.8.0).

Production impact:

If left unfixed, the same config can fail only in production (env differences), causing startup failures or partial feature outages.

Why This Breaks in Prod

The required version of pytest was not updated, causing compatibility issues
Production symptom (often without a traceback): - [ ] [Compatibility between releases](https://docs.pydantic.dev/changelog/)

Proof / Evidence

GitHub issue: #9597
Fix PR: https://github.com/pydantic/pydantic/pull/9702
First fixed release: 2.8.0
Reproduced locally: No (not executed)
Last verified: 2026-02-09
Confidence: 0.85
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.72

Discussion

High-signal excerpts from the issue thread (symptoms, repros, edge-cases).

Jump to Sources Open on GitHub

“@s-t-e-v-e-n-k, Would you be willing to open a PR bumping the version and updating the tests that you modified in terms of warnings? As long…”

@sydney-runkle · 2024-06-07 · source

“@s-t-e-v-e-n-k, Yep, agreed! We should probably check out download numbers for the different pytest versions.”

@sydney-runkle · 2024-06-07 · source

“@s-t-e-v-e-n-k, Going to work on getting v2.8 out soon - any chance you can pick this up in the next week or so?”

@sydney-runkle · 2024-06-19 · source

“@sydney-runkle I have been working on it as I can, I hope to finish it up this week.”

@s-t-e-v-e-n-k · 2024-06-20 · source

Failure Signature (Search String)

- [ ] [Compatibility between releases](https://docs.pydantic.dev/changelog/)
- [ ] [Data validation/parsing](https://docs.pydantic.dev/concepts/models/#basic-model-usage)

Copy-friendly signature

signature.txt

Failure Signature
-----------------
- [ ] [Compatibility between releases](https://docs.pydantic.dev/changelog/)
- [ ] [Data validation/parsing](https://docs.pydantic.dev/concepts/models/#basic-model-usage)

Error Message

Signature-only (no traceback captured)

error.txt

Error Message
-------------
- [ ] [Compatibility between releases](https://docs.pydantic.dev/changelog/)
- [ ] [Data validation/parsing](https://docs.pydantic.dev/concepts/models/#basic-model-usage)

What Broke

Users experienced warnings and compatibility issues when using pytest 7.4.

Why It Broke

The required version of pytest was not updated, causing compatibility issues

Fix Options (Details)

Option A — Upgrade to fixed release Safe default (recommended)

pip install pydantic==2.8.0

When NOT to use: Do not use if it changes public behavior or if the failure cannot be reproduced.

Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.

Fix reference: https://github.com/pydantic/pydantic/pull/9702

First fixed release: 2.8.0

Last verified: 2026-02-09. Validate in your environment.

When NOT to Use This Fix

Do not use if it changes public behavior or if the failure cannot be reproduced.

Did This Fix Work in Your Case?

Quick signal helps us prioritize which fixes to verify and improve.

Prevention

Add a CI check that diffs key outputs after upgrades (OpenAPI schema snapshots, JSON payload shapes, CLI output).
Upgrade behind a canary and run integration tests against the canary before 100% rollout.

Version Compatibility Table

Version	Status
2.8.0	Fixed

Related Issues

No related fixes found.

Cluster: pydantic:configuration-error Pydantic hub Pydantic best practices All hubs All clusters

Related clusters: Data consistency OpenAPI schema Serialization

Sources

We don’t republish the full GitHub discussion text. Use the links above for context.