Error when passing zero area polygon to h3.polygonToCells about h3-js

[kbajori50]

const h3 = require('h3-js');
const turf = require('@turf/turf');
const zeroAreaPolygon = [
[0, 0],
[0, 90],
[0, 90],
[0, 0],
];
const geojson = turf.polygon([zeroAreaPolygon]);
const area = turf.area(geojson);
if (area === 0) {
console.log('Zero area polygon, skipping');
// This is a weird case, why would you have a zero area polygon?
} else {
// Pass the polygon to h3.polygonToCells
const cells = h3.polygonToCells(zeroAreaPolygon, 1);
console.log(cells);
// This should give you an array of hexagonal cells that cover the polygon
}

[nrabinowitz]

Technically this is expected behavior for h3-js - we are simply proxying the errors from the underlying C library. For this particular issue, the error is expected - the first step of the polygonToCells algorithm is to take the bounding box of the input polygon and estimate the number of cells it will contain. If the bounding box is zero-width or zero-height, we throw this error.

I do think it would make more sense to have the option to have h3-js throw fewer errors, however, and I plan to update the binding to offer a less strict option. It's been the subject of some debate whether it would be better to throw errors, which are generally clear and explicit, or return fallbacks like null and [] on failure, which are easier and more efficient for JS applications to handle.