fix: support optional params in Netlify split mode

[anurag6569201]

closes sveltejs#9825

This maps [[optional]] segments to URLPattern's native optional named-parameter syntax (:param?).

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Summary by CodeRabbit

• Bug Fixes

  • Fixed Netlify split-function routing for requests where optional URL parameters are omitted.
  • Improved generated function names and route matching for optional and rest parameters.

• Tests

  • Added coverage for routes with optional parameters both present and absent.
  • Verified that generated functions include all expected route paths.

Source merge-base: 3b688deb803e77ab39c2c7adf81c5c3c168f73d7
Source head: 1a9f6b8b3d34e9eb97d49c783e82b9d1fc057245

[shipwright-agent]

⛔ Shipwright · Blocked

Recommendation: do not merge PR #7 · Tier T1
Checks: 0 total · 0 needing attention

Next step: resolve the blocking findings before merge.

Findings (3)

• CRITICAL The function name generation uses 'parts.join('-')' where 'parts' now contains ':param1?'. · packages/adapter-netlify/index.js:163
  • Fix: Review the cited evidence, fix the risk if confirmed, and rerun Shipwright.
• CRITICAL The optional parameter detection uses a regex '/^[[.+]]$/' on 'segment.content'. · packages/adapter-netlify/index.js:152
  • Fix: Review the cited evidence, fix the risk if confirmed, and rerun Shipwright.
• HIGH The variable shadowing in 'patterns.forEach((pattern) => seen.add(pattern))' reuses the name 'pattern' for the loop parameter, shadowing the outer 'const pattern'. · packages/adapter-netlify/index.js:171
  • Fix: Review the cited evidence, fix the risk if confirmed, and rerun Shipwright.

Fireworks usage: 7,879 input · 546 output · 8,425 total tokens · $0.0021 · 12s · 0 fix iteration(s)

Open the Shipwright check for full evidence and the audit bundle. Use /shipwright rerun to verify again.

[shipwright-agent]

Shipwright · CRITICAL

The function name generation uses 'parts.join('-')' where 'parts' now contains ':param1?'.

Impact: The function name generation uses 'parts.join('-')' where 'parts' now contains ':param1?'. The '.replace(/[:.]/g, '_')' runs before '.replace(/?/g, '')', so the '?' is removed, but the test expects the file 'sveltekit-collection-_param1-article.mjs'. However, for a route with multiple optional params or a rest segment combined with optional params, the '?' removal can create name collisions. More critically, the 's…

Suggested fix: Review the cited evidence, fix the risk if confirmed, and rerun Shipwright.

[shipwright-agent]

Shipwright · HIGH

The variable shadowing in 'patterns.forEach((pattern) => seen.add(pattern))' reuses the name 'pattern' for the loop parameter, shadowing the outer 'const pattern'.

Impact: The variable shadowing in 'patterns.forEach((pattern) => seen.add(pattern))' reuses the name 'pattern' for the loop parameter, shadowing the outer 'const pattern'. This is confusing and error-prone; a future maintainer modifying the loop body may inadvertently reference the wrong 'pattern'. The original code used 'p' to avoid this. This change reduces clarity without functional benefit.

Suggested fix: Review the cited evidence, fix the risk if confirmed, and rerun Shipwright.