[Vl4dC]

Issue number: closes #8682

Summary

Changes

• Check whether the key exists before updating LRUDict recency. This preserves get defaults for missing keys and updates recency for cached falsey values.
• Add regression tests for both cases.
• Correct the cache docstring to describe least-recently-used eviction.

User experience

LRUDict.get("missing", "fallback") now returns "fallback" instead of raising KeyError. Reading a cached False, 0, None, or empty string now protects that entry from being evicted as the least recently used item. Existing callers using truthy cached values retain their behavior.

Verification

• uv run --locked --no-default-groups --with pytest --with ruff --python 3.12 pytest tests/unit/test_lru_cache.py -q — 11 passed, 1 pre-existing skip.
• Ruff lint and format checks passed for both changed files.

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[boring-cyborg]

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[leandrodamascena]

Thanks @Vl4dC, and welcome. Confirmed both halves on develop: a missing key with a truthy default raised KeyError, and a falsy cached value lost its recency and got evicted right after being read. key in self is the right check, and the docstring fix is welcome too. Our current callers don't hit either case, but the contract was wrong and your tests pin it. Approving, this goes out in 3.39.0, no rebase needed, and you'll be credited in the release notes.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.99%. Comparing base (486e484) to head (9b29655).
⚠️ Report is 1 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8683   +/-   ##
========================================
  Coverage    96.99%   96.99%           
========================================
  Files          321      321           
  Lines        16332    16332           
  Branches      1473     1473           
========================================
  Hits         15841    15841           
  Misses         350      350           
  Partials       141      141           

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[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!

[powertools-for-aws-oss-automation]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!