Improve performance of select_children() and select_parents()

[peterallenwebb]

Problem

The select_children() and select_parents() functions have been identified as performance bottlenecks, particularly as they are used via semantic layer code.

We've received reports of projects spending over 15 minutes waiting for these operations.

Solution

The present changes are behavior-neutral, but they avoid the repeated application of networkx graph views, which are slow. We already have some unit tests covering these functions, but went further and tested that the new functions gave the same results as the old on a large set of real-world graphs, choosing sets of "selected" nodes at random at a variety of sizes. I observed a reliable speedup of 60-100x for select_children() and 20-30x for select_parents().

This should reduce the project time mentioned above from 15 minutes to less than 15 seconds.

Checklist

• I have read the contributing guide and understand what's expected of me.
• I have run this code in development, and it appears to resolve the stated issue.
• This PR includes tests, or tests are not required or relevant for this PR.
• This PR has no interface changes (e.g., macros, CLI, logs, JSON artifacts, config files, adapter interface, etc.) or this PR has already received feedback and approval from Product or DX.
• This PR includes type annotations for new and modified functions.

[github-actions]

Thank you for your pull request! We could not find a changelog entry for this change. For details on how to document a change, see the contributing guide.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.13%. Comparing base (ff6745c) to head (3a7c52d).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #11099      +/-   ##
==========================================
- Coverage   89.13%   89.13%   -0.01%     
==========================================
  Files         183      183              
  Lines       23784    23782       -2     
==========================================
- Hits        21200    21198       -2     
  Misses       2584     2584              

Flag	Coverage Δ
integration	86.41% <100.00%> (-0.04%)	⬇️
unit	62.20% <100.00%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
Unit Tests	62.20% <100.00%> (-0.01%)	⬇️
Integration Tests	86.41% <100.00%> (-0.04%)	⬇️