fix: detect any non-main thread, not just ThreadPoolExecutor by name

[selmanozleyen]

The fact that we check by string matching "ThreadPoolExecutor" seems brittle to me. Even if it's the only option we should've document it as an assumption because in cases like ThreadPoolExecutor(thread_name_prefix=...) this fails. And probably also in joblib it will fail.

Instead why don't we check if the caller is inside the main thread or not? I checked with jupyter and the executor there is in main thread as well.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.32%. Comparing base (4fa33a0) to head (5a1f5da).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #212      +/-   ##
==========================================
- Coverage   99.33%   99.32%   -0.01%     
==========================================
  Files          21       21              
  Lines         598      597       -1     
==========================================
- Hits          594      593       -1     
  Misses          4        4              

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[codspeed]

Merging this PR will improve performance by 11.23%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 2 improved benchmarks
✅ 230 untouched benchmarks

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	test_to_dense_benchmark[scipy.sparse.csc_array-float64-C]	83.1 ms	74.4 ms	+11.76%
⚡	test_to_dense_benchmark[scipy.sparse.csr_matrix-float32-F]	77.2 ms	69.7 ms	+10.7%

Tip

Curious why performance improved? Comment @codspeedbot explain why performance improved on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing selmanozleyen:refactor/no-thread-string-matching (5a1f5da) with main (4fa33a0)}

[flying-sheep]

Great, thank you!

I think the only reason we don’t do that is that I lifted that implementation from somewhere else and didn’t know that there’s a better way.