Steps to reproduce:
1. Create new Unity project using Universal 2D Template
2. Install Splines package via Package Manager window
3. In Hierarchy select Draw Splines Tool (Splines > Draw Splines Tool)
4. In Scene View draw a Square using Splines Tool
5. Select any Knot in the Scene
6. In Scene view > Element Inspector Overlay > Knot Rotation enter “NaN” or “Infinity” value in X value field
7. Observe the Console window
Actual results: Errors are spammed in the Console window “Assertion failed on expression: 'CompareApproximately(SqrMagnitude(result), 1.0F)’”,
“Quaternion To Matrix conversion failed because input Quaternion is invalid
{nan, nan, nan, nan}
l=nan”,
“QuaternionToEuler: Input quaternion was not normalized”
Expected results: “NaN” and “Infinity” values area rejected and reverted back to previous valid value, no errors are thrown in the Console window
Reproducible with versions: 6000.0.74f1, 6000.3.14f1, 6000.4.6f1, 6000.5.0b7, 6000.6.0a4
Tested on (OS): macOS Silicon Tahoe 26.4.1