@turf/boolean-point-in-polygon fails to check for points on edges, loads wrong version of library

[jsnoble]

Downloading from scratch @turf/boolean-point-in-polygon currently is not able to check for edge points. Below is a code example to replicate the issue

package.json

{
  "name": "geo-test",
  "version": "1.0.0",
  "type": "module",
  "main": "index.js",
  "license": "MIT",

  "dependencies": {
    "@turf/boolean-point-in-polygon": "~7.1.0",
    "@turf/helpers": "~7.1.0"
  }
}

code

import { point, polygon } from '@turf/helpers';
import { booleanPointInPolygon } from '@turf/boolean-point-in-polygon';

const polyCoordinates = [
    [
        [140.43, 70.43],
        [154.4, 89.3],
        [123.4, 81.3],
        [140.43, 70.43]
    ]
]

const pt = point([ 140.43, 70.43 ]);
const poly = polygon(polyCoordinates)

const bool = booleanPointInPolygon(pt, poly);
bool === false // should be true

After diving deeper into the issue, it seems to come from a library used internally that is returning a wrong value (false instead of 0). The library in question is point-in-polygon-hao and I just recently made a ticket herehttps://github.com/rowanwins/point-in-polygon-hao/issues/23.

You have listed in your package.json to set that library to "^1.1.0". I verified that that version does in fact work, however a fresh install will give you 1.2.3 which breaks.

This is due to how semver works with the ^ symbol, "^1.1.0" will give you anything between anything >= 1.1 AND < 2. If you adjust your install to use ~, it will give you >= 1.1 AND < 1.2, or just locking it down completely to an exact version. Its unfortunate that package installs usually default to ^

I can lucky fix this by setting up resolutions in my personal package.json (for others to see, im using yarn)

{
  "name": "geo-test",
  "version": "1.0.0",
  "type": "module",
  "main": "index.js",
  "license": "MIT",
  "resolutions": {
    "point-in-polygon-hao": "~1.1.0"
  },
  "dependencies": {
    "@turf/boolean-point-in-polygon": "~7.1.0",
    "@turf/helpers": "~7.1.0"
  }
}

However I still recommend to lock down the 1.1.0 or use ~ instead of the ^ as that is far to loose and you rely a bit to much on others not breaking code in minor semver updates. This exact issue has bitten me a few times over the past few months for other libraries

[xThrodx]

This should be fixed with the latest release of point-in-polygon-hao.

I had a similar problem with a point in the middle of a polygon that was wrongly determined to be outside of the polygon.

It might be a good idea to lock the dependencies, however for this particular problem neither the tests of Turf.js nor those of point-in-polygon-hao caught this regression.

Edit: My bad, Turf would have caught that in its tests.

[smallsaucepan]

Hi @jsnoble and @xThrodx thanks for your help with this one. Will mark as resolved given it's been fixed upstream

You've raised a good point though. We'll discuss it amongst the maintainers and see if it's something we should adopt 👍