[tdamsma]

A caller-supplied NURBS control-point count can overflow the required knot count before the evaluator rejects malformed dimensions. The dimension predicate now checks both additions, preserving the existing unevaluable result for invalid inputs.

Fixes #2751. Refs #2490.

The allocation-free public-API reproducer panics before the fix. The regression exercises EvalSurface::nurbs and nurbs_closed, either parameter direction, and counts that overflow n + p or its following + 1. Valid surfaces use the same dimension checks and numerical operations.

Validation at 974e33f1a, with main a91e108c8 integrated:

• Optimized, overflow-checked kernel library suite: 3,523 passed, 4 ignored.
• Kernel wasm32 check: passed.
• Affected-crate clippy, all targets, warnings denied: passed.
• Workspace formatting: passed.

Only the basis-dimension predicate and the existing evaluator test file change. #2726's projection callbacks are outside this scope. This fixes an overflow-check build panic; no release-build memory-safety or application/import reproduction is claimed. No public interface or tolerance changes.

Summary by CodeRabbit

• Bug Fixes
  • NURBS evaluation now safely handles extreme control-point counts, returning an error or no derivatives instead of proceeding with an invalid knot vector.
• Tests
  • Added coverage for oversized control-point counts across standard and closed surface construction.

[coderabbitai]

Walkthrough

basis_check now uses checked additions to validate the required knot count. Regression tests cover overflowing NURBS control counts and verify that derivs returns None and eval returns an error.

Changes: NURBS overflow validation

Layer / File(s)	Summary
Basis validation and regression coverage crates/solidcore/src/eval/spline.rs, crates/solidcore/src/eval/tests.rs	basis_check rejects knot-count calculations that overflow. Tests cover extreme control counts in both directions for nurbs and nurbs_closed.

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Bug fix · Severity of issue fixed: Low

Possibly related PRs

• tangency-labs/solidcore#2629: Introduced the evaluator and its knot-vector dimension validation, which this PR updates.
• tangency-labs/solidcore#2745: Hardens a separate spline predicate against overflow in required knot-count arithmetic.

Suggested reviewers: jyviko

Merge Risk: Minimal · up to 974e3

No actionable merge-blocking risk was identified in the overflow validation change.

Pre-merge checks: 4 · 1

Failed checks: 1 warning

Check name	Status	Explanation	Resolution
Docstring Coverage		Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documenta…	Write docstrings for the functions missing them to satisfy the coverage threshold.

Passed checks: 4 passed

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Title check		The title clearly and concisely describes the main change: preventing the NURBS evaluator from accepting overflowing control counts.
Linked Issues check		The direct target is #2751. basis_check now uses checked additions for n + p and the following + 1, so overflow returns false instead of panicking. EvalSurface::nurbs_closed uses this predic…
Out of Scope Changes check		The diff changes only the NURBS basis-dimension predicate and adds a focused regression test in the existing evaluator test file. Both changes directly support #2751. The diff contains no unrelated pr…

Full details: Linked Issues check

Explanation

The direct target is #2751. basis_check now uses checked additions for n + p and the following + 1, so overflow returns false instead of panicking. EvalSurface::nurbs_closed uses this predicate before constructing the NURBS evaluator. The added regression test covers nurbs and nurbs_closed, both parameter directions, and counts that overflow either addition. It asserts derivs returns None and eval returns an error. Valid dimensions retain the existing predicate and evaluation path.

Full details: Out of Scope Changes check

Explanation

The diff changes only the NURBS basis-dimension predicate and adds a focused regression test in the existing evaluator test file. Both changes directly support #2751. The diff contains no unrelated projection callbacks, public-interface changes, tolerance changes, or unrelated behavior changes.

Full details: Docstring Coverage

Explanation

Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documentation-only edits and deletions within surviving functions are included; unchanged diff context and fully deleted functions are excluded. Analyzed 2 functions across 2 files.

Resolution

Write docstrings for the functions missing them to satisfy the coverage threshold.

Finishing Touches

Generate unit tests (beta)

• Create a new PR

• Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

[coderabbitai]

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only still-valid issues, skip the rest with a brief reason, keep changes
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Failed pre-merge checks:
- Docstring Coverage:
Write docstrings for the functions missing them to satisfy the coverage
threshold.

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Review info

Run configuration

• Source mode: Auto
• Repository: tangency-labs/solidcore
• Branch: main
• File: .coderabbit.yaml
• Commit: a91e108
• Layers: Repository YAML
• Review profile: CHILL
• Plan: Advanced
• Run ID: f78e0a7e-070e-4ba6-974e-06a0ad77ab71

Commits

Reviewing files that changed from the base of the PR and between a91e108 and 974e33f.

Files selected for processing: 2

• crates/solidcore/src/eval/spline.rs
• crates/solidcore/src/eval/tests.rs

Included review availability: This review used your included allowance. Your plan provides up to 10 included reviews per hour; 6 remain after this review.

[bherbruck]

Approved by the automated first-pass review: CI green, mergeable, no CI/build/dependency file changes, no red-flag patterns in added code (process/network/env/unsafe outside FFI/blobs/hidden unicode), 0 known-mismatch entries added. Logic is gated by CI and the difftest merge queue.