Improve test-local phase reporting and stabilize MongoDB CI

[shaypal5]

Closes #362.

Summary

• Capture the main pytest phase exit code immediately after it runs.
• Capture the optional serial local pytest phase exit code separately.
• Aggregate the final script exit code explicitly and report which phase passed, failed, or was skipped.
• Keep running the serial local phase when it is requested, even if the main phase fails.
• Stabilize MongoDB CI by avoiding Dockerized MongoDB on GitHub-hosted Windows runners, where the Docker daemon is not reliably available.
• Keep live Dockerized MongoDB coverage on non-Windows runners while using the existing pymongo_inmemory path for Windows MongoDB matrix jobs.
• Split MongoDB CI test steps into explicit Docker and in-memory paths instead of using an inline boolean expression.
• Scope the pymongo_inmemory tarfile deprecation warning filter to in-memory Mongo client startup, preserving the repo's -W error posture without mutating global tarfile behavior.

Validation

• bash -n scripts/test-local.sh
• Stubbed pytest to verify main phase failure exits non-zero, still runs serial local tests, and reports the main phase failure.
• Stubbed pytest to verify serial local failure exits non-zero and reports the serial phase failure.
• Stubbed pytest to verify both phases passing exits zero.
• ./scripts/test-local.sh pickle
• CACHIER_TEST_VS_DOCKERIZED_MONGO=false pytest -m mongo --cov=cachier --cov-report=term
• Parsed .github/workflows/ci-test.yml with PyYAML.
• ruff check tests/mongo_tests/helpers.py
• git diff --check

CI scope note

The PR now intentionally changes CI behavior: Windows MongoDB matrix jobs no longer attempt to start a Linux MongoDB container through Docker. Non-Windows MongoDB matrix jobs still run against a live Dockerized MongoDB service and remain the live-Mongo compatibility signal. Windows MongoDB matrix jobs remain useful compatibility coverage over the Mongo backend API using pymongo_inmemory.

Milestone

No open repository milestones are currently available, so none was assigned.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.95%. Comparing base (92fce34) to head (52d5492).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #389   +/-   ##
=======================================
  Coverage   99.95%   99.95%           
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  Files          16       16           
  Lines        2109     2109           
  Branches      251      251           
=======================================
  Hits         2108     2108           
  Partials        1        1           

Flag	Coverage Δ
local	66.57% <ø> (ø)
mongodb	40.01% <ø> (ø)
postgres	42.05% <ø> (ø)
redis	44.57% <ø> (ø)
s3	41.29% <ø> (ø)

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[Copilot]

Pull request overview

Improves local test script phase reporting/exit-code aggregation and stabilizes MongoDB CI by avoiding Dockerized MongoDB on GitHub-hosted Windows runners while keeping live MongoDB coverage on Linux. Also updates the Mongo test helper to opt into Python’s safe tar extraction behavior for the in-memory Mongo path under stricter warning settings.

Changes:

• Refactors scripts/test-local.sh to capture and report separate exit codes/statuses for the main pytest phase and optional serial-local phase, then aggregates a final exit code.
• Updates GitHub Actions MongoDB matrix behavior to skip Dockerized MongoDB startup on Windows and select in-memory Mongo there, while keeping Dockerized Mongo on Linux.
• Adds a tarfile extraction filter configuration hook before instantiating pymongo_inmemory’s Mongo client, and updates README wording to match the new CI behavior.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
tests/mongo_tests/helpers.py	Configures tarfile extraction filter before creating an in-memory MongoDB client.
scripts/test-local.sh	Adds a helper for phase execution/reporting and explicitly aggregates per-phase exit codes.
README.rst	Updates documentation to reflect Linux live-Mongo vs Windows in-memory CI behavior.
.github/workflows/ci-test.yml	Skips Dockerized Mongo on Windows and sets CACHIER_TEST_VS_DOCKERIZED_MONGO per Mongo test step.