Cleaning up test work and changing the get_degree_stats signature.

[JordanMaples]

This is a quick cleanup PR for some of the changes that went in the other day.

In test/cases/index.rs there were a bunch of paged_search tests that on the whole are lower signal than the baseline-related paged_search tests added in a different PR, so those are being removed.

tests for the QueryLabelProvider were moved to the trait defn location for additional documentation purposes on how we intend the trait to be used.

In the initial test authoring, I added an IntoIterator trait implementation to the test provider in the goals of testing get_degree_stats. After syncing with Mark, we agreed that the better approach was to change the way that get_degree_stats behaves, now it accepts an iterator to the ids that you want the degree stats for rather than forcing the provider to implement IntoIterator.

There are still some areas that I'm cleaning up. In particular: helpers.rs, while it does help to set up some tests, naming is not the best and there are still some layers of boilerplate that can be eliminated by spending a bit more time handcrafting a solution.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 88.39286% with 13 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.47%. Comparing base (d2ec7d0) to head (0e1bdf6).
⚠️ Report is 6 commits behind head on main.

Files with missing lines	Patch %	Lines
diskann/src/graph/index.rs	76.00%	6 Missing ⚠️
diskann-providers/src/index/wrapped_async.rs	0.00%	4 Missing ⚠️
diskann/src/graph/test/provider.rs	87.50%	3 Missing ⚠️

❌ Your patch status has failed because the patch coverage (88.39%) is below the target coverage (90.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #998      +/-   ##
==========================================
- Coverage   90.69%   89.47%   -1.22%     
==========================================
  Files         459      460       +1     
  Lines       85030    85327     +297     
==========================================
- Hits        77115    76344     -771     
- Misses       7915     8983    +1068     

Flag	Coverage Δ
miri	89.47% <88.39%> (-1.22%)	⬇️
unittests	89.31% <88.39%> (-1.34%)	⬇️

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

Files with missing lines	Coverage Δ
diskann-providers/src/index/diskann_async.rs	96.01% <100.00%> (+0.02%)	⬆️
diskann/src/graph/test/cases/consolidate.rs	97.65% <100.00%> (ø)
diskann/src/graph/test/cases/helpers.rs	97.64% <100.00%> (-0.09%)	⬇️
diskann/src/graph/test/cases/index.rs	98.03% <100.00%> (-0.69%)	⬇️
diskann/src/graph/test/cases/inplace_delete.rs	95.76% <100.00%> (ø)
diskann/src/graph/test/provider.rs	94.16% <87.50%> (-0.25%)	⬇️
diskann-providers/src/index/wrapped_async.rs	45.88% <0.00%> (-0.14%)	⬇️
diskann/src/graph/index.rs	95.45% <76.00%> (-0.83%)	⬇️

... and 65 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Cleans up and reorganizes test utilities while changing get_degree_stats to accept an explicit iterator of IDs (instead of requiring providers to implement IntoIterator).

Changes:

• Updated get_degree_stats (and sync wrapper) to take an IntoIterator of IDs to compute degree stats for.
• Removed/relocated lower-signal tests and improved test assertions for DegreeStats.
• Simplified 2D-square test setup helpers and refactored neighbor access in the test provider.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
diskann/src/graph/test/provider.rs	Adds ID iterators + refactors neighbor retrieval; removes IntoIterator impl.
diskann/src/graph/test/cases/inplace_delete.rs	Adapts tests to new setup_2d_square helper signature.
diskann/src/graph/test/cases/index.rs	Removes paged-search tests; updates degree-stats tests for new API.
diskann/src/graph/test/cases/helpers.rs	Simplifies helper by internalizing vector generation (removes Matrix param).
diskann/src/graph/test/cases/consolidate.rs	Adapts consolidation tests to new helper signature.
diskann/src/graph/index.rs	Changes get_degree_stats signature; moves QueryLabelProvider test here; adds verbose-eq for DegreeStats.
diskann-providers/src/index/wrapped_async.rs	Updates sync wrapper to pass ID iterator through to async API.
diskann-providers/src/index/diskann_async.rs	Updates provider-side tests to pass iterators into get_degree_stats.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[hildebrandmw]

Just a small couple requests - otherwise looks good. Thanks!