Add test for function reliant on turf dependency

[cafca]

We are using turf only for this single piece of code and therefore are not tracking changes in turf releases. To guard against breaking api changes in future turf releases etc. we should add a test for this function.

fixmy.frontend/src/apps/Map/map-utils.js

Lines 176 to 190 in e9ed240

	export function getCenterFromGeom(geometry, defaultCenter = null) {
	if (geometry && geometry.coordinates) {
	if (geometry.type === 'MultiLineString') {
	geometry = turfLineString(
	geometry.coordinates.reduce((res, coord) => res.concat(coord)),
	[]
	);
	}
	const length = turfLength(geometry);
	return turfAlong(geometry, length * 0.5).geometry.coordinates;
	}
	return defaultCenter;
	}

This is a good issue for first contributors. Please leave a message here if you would like assistance.

[s-pic]

@tordans @cafca Can I tackle that?

[tordans]

@s-pic I will not be able to help much (not knowing this part of the code yet and not being "fluent" in unit tests, yet :)), but yes, feel free. CC @ohrie.
I see those places currently using turf:

package.json:
  42      "@material-ui/styles": "^4.11.4",
  43:     "@turf/along": "6.0.1",
  44:     "@turf/boolean-within": "^6.0.1",
  45:     "@turf/center": "^6.3.0",
  46:     "@turf/helpers": "^6.1.4",
  47:     "@turf/length": "^6.3.0",
  48      "abortcontroller-polyfill": "^1.7.3",

src/apps/Gastro/components/AreaMap.tsx:
   1: import turfCenter from '@turf/center';
   2  import MapboxGL, { LngLatLike } from 'mapbox-gl';

  43    if (showAreaPin) {
  44:     const center = turfCenter(area);
  45      new MapboxGL.Marker({ color: config.colors.interaction })

src/apps/Map/map-utils.ts:
    1: import turfAlong from '@turf/along';
    2: import { lineString as turfLineString } from '@turf/helpers';
    3: import turfLength from '@turf/length';
    4  import debug from 'debug';

  191      if (geometry.type === 'MultiLineString') {
  192:       lineString = turfLineString(
  193          geometry.coordinates.reduce((res, coord) => res.concat(coord)),

  197  
  198:     const length = turfLength(lineString);
  199:     return turfAlong(lineString, length * 0.5).geometry.coordinates;
  200    }

src/pages/Reports/state/SubmitReportState.js:
  1  /* eslint-disable  no-multi-spaces */
  2: import booleanWithin from '@turf/boolean-within';
  3  

[s-pic]

Nice. Will try to add proper types (get rid of the any annotation for the first function arg) as well.