[Jens Hedegaard Nielsen (jenshnielsen)]

Replace the Literal["NOT_PASSED"] string marker with a typing_extensions Sentinel, compare by identity, and require typing_extensions>=4.16.0 for the test extra.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.05%. Comparing base (7d4c4fa) to head (78c9505).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8706   +/-   ##
=======================================
  Coverage   75.05%   75.05%           
=======================================
  Files         307      307           
  Lines       32545    32545           
=======================================
  Hits        24426    24426           
  Misses       8119     8119           

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[Copilot]

🟡 Changes recommended

The PR is missing the required newsfragment describing the sentinel migration and updated test dependency.

1 open issue

• Add a newsfragment for the sentinel migration · New

What changed in this PR

This PR replaces the string-based NOT_PASSED marker with a typing_extensions.Sentinel in QCoDeS parameter tests, preserving the distinction between omitted arguments and explicit values.

Changes:

• Define a shared sentinel and update fixture and test annotations.
• Use identity comparisons when checking for omitted arguments.
• Require typing_extensions>=4.16.0 in the test extra.

File	Description
tests/​parameter/​test_snapshot.py	Update snapshot test annotations and sentinel comparisons.
tests/​parameter/​test_parameter_cache.py	Update cache test annotations and sentinel comparisons.
tests/​parameter/​conftest.py	Define the sentinel and update fixture return types.
pyproject.toml	Add the minimum test dependency for sentinel support.

_{Review effort: Balanced}