EllipseConverter, SplineConverter and GeometrySimplifier each carried an
identical private SumSignedAngles. Move the unchanged body to
ArcFit.SumSignedAngles and call it from all three, keeping the ordered
accumulation, strict half-turn comparisons and empty/single-point result.
ArcFitTests compares the shared method bit-for-bit with a separate
test-local accumulator across half turns, the atan2 seam, multiple
turns, translated centres and NaN inputs, and checks that inputs are not
mutated. The converter winding characterization from 8664656 still
passes unchanged.
Repo-wide sweep with the pinned CSharpier 1.3.0 tool. Whitespace and
line-wrapping only; OpenNest.Engine.Tests (109) and OpenNest.IO.Tests
pass after reformat, full solution builds 0 errors.
Added .csharpierignore so csproj/config XML keeps its existing layout
(CSharpier's XML wrapping churns attributes with zero benefit).
Formatting is now enforceable: dotnet csharpier check . passes.
Move identical FitWithStartTangent and MaxRadialDeviation methods
to a shared ArcFit class, eliminating 40-line duplicate.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>