Speed up IslandPruningModule with a cheaper edge-traversability check

[leonardehrenfried]

Summary

Speeds up IslandPruningModule (the graph-builder step that detects small disconnected "islands" of the street graph and prunes or no-thru's them) by replacing the per-edge StreetEdge.traverse() call in collectNeighbourVertices() with the existing, allocation-free StreetEdge.canTraverse(TraverseMode) permission check. Benchmarked on a full Norway OSM extract (3 runs on each side), this is a reproducible ~7-8% speedup for island pruning, with identical output (same edges removed/restricted/marked no-thru).

Also adds a standalone benchmark, IslandPruningBenchmark (in test-fixtures, not run by CI), that downloads a full-country OSM extract, builds the street graph, and times island pruning in isolation - the existing unit tests only exercise small fixtures, and this module is specifically CPU/memory sensitive at country scale.

Issue

No linked issue - this is a self-contained performance cleanup.

Motivation: IslandPruningModule.collectNeighbourVertices() calls e.traverse(s0) for every outgoing edge of every street vertex, once per travel mode (WALK/BICYCLE/CAR), purely to learn whether an edge is usable and which vertex it leads to - the resulting State's cost/weight is discarded. traverse() still allocates a StateEditor, computes walk/bike speed and slope-adjusted cost, and builds a State object for every edge, none of which this module needs.

How the code works / approach: StreetEdge already exposes canTraverse(TraverseMode), a permission + barrier-vertex check with no allocation. collectNeighbourVertices() now uses that directly for plain StreetEdge/AreaEdge instances (keeping the same "dismount and walk the bike" fallback StreetEdge.traverse() applies for BICYCLE mode), and only falls back to a real traverse() call for edge types that don't behave like a simple permission-gated street edge (escalators, pathways, vehicle rental/parking edges).

[codecov]

Codecov Report

❌ Patch coverage is 88.46154% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 74.62%. Comparing base (161c13d) to head (e2677ce).
⚠️ Report is 146 commits behind head on dev-2.x.

Files with missing lines	Patch %	Lines
...lder/module/islandpruning/IslandPruningModule.java	88.46%	1 Missing and 2 partials ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             dev-2.x    #8028      +/-   ##
=============================================
+ Coverage      74.57%   74.62%   +0.04%     
- Complexity     22708    22880     +172     
=============================================
  Files           2514     2533      +19     
  Lines          87945    88526     +581     
  Branches        8690     8752      +62     
=============================================
+ Hits           65589    66064     +475     
- Misses         19307    19394      +87     
- Partials        3049     3068      +19     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[habrahamsson-skanetrafiken]

It looks like you forgot to actually fetch the visibilityVertices?

[leonardehrenfried]

Okay, that was pretty embarrassing.

In order for this to not happen again I added a module test for this very feature and fixed the code.