TurfMeasurement#length method cannot handle empty lists

[Blafasel3]

The other day, I encountered what I regard as an issue in the following Code snippet:

mapbox-java/services-turf/src/main/java/com/mapbox/turf/TurfMeasurement.java

Line 227 in 4ae8b78

Point prevCoords = coords.get(0);

The scenario is the following: We have a list of GPS points of which some or all are invalid which is denoted by the coordinates being (0 , 0) - which IS bad Design, but our Team cannot change this... 🙄. Thus, we filter out those points before passing it to the length method. We just encountered an IndexOutOfBoundsException when the list is empty because there is no length check on the list. I guess the fix here is relatively easy, but the question ist - what should be returned in this case. We built in a check before hand returning 0 in this particular case. Maybe even a checked exception might be a feasible idea.