Fix NaN handling in LinearLocation/EdgeIntersection compareTo - #1229
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compareTo() used raw </> comparisons on segmentFraction/dist, which are always false for NaN and made compareTo (and thus equals(), added in locationtech#1201) fall through to 0 whenever NaN was compared to any other value on the same segment/index. This broke transitivity of equals() and its consistency with hashCode(). Use Double.compare() instead, matching Double's NaN ordering semantics already used by hashCode().
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Fixes #1228
LinearLocation.compareTo()andEdgeIntersection.compare()compared the floating-point fields (segmentFraction/dist) with raw</>, which are alwaysfalseforNaN. This madecompareTofall through toreturn 0("equal") whenever aNaNwas compared against any other value on the same segment/index, not just against anotherNaN.Since
equals()for both classes (added in #1201) is defined ascompareTo(o) == 0, this madeequals()non-transitive and inconsistent withhashCode()wheneverNaNwas involved (e.g.segmentFractionisNaNfor zero-length line segments).Fix
Replace the manual
</>comparisons withDouble.compare(), which givesNaNa well-defined, transitive ordering consistent withDouble.hashCode()/Objects.hash()(already used by both classes'hashCode()). No behavior change for non-NaNvalues.Tests
Added regression tests reproducing the transitivity/hashCode issue from the report:
LinearLocationTest.testEqualsHashCodeConsistentWithNaNEdgeIntersectionTest.testEqualsHashCodeConsistentWithNaN