formatUnits: instead of 'format-unit' use newer 'measure-ts'

package.json

@@ -20,7 +20,6 @@
     "color-interpolate": "^1.0.5",
     "event-emitter": "^0.3.5",
     "file-saver": "^2.0.0",
-    "format-unit": "^1.0.6",
     "formatcoords": "^1.1.3",
     "i18next-client": "^1.11.4",
     "ip-location": "^1.0.1",
@@ -32,6 +31,7 @@
     "leaflet.locatecontrol": "^0.61.0",
     "leaflet.polylinemeasure": "git+https://github.com/ppete2/Leaflet.PolylineMeasure.git",
     "md5": "^2.2.1",
+    "measure-ts": "^3.3.2",
     "modulekit-tabs": "^0.2.2",
     "moment": "^2.18.1",
     "natsort": "^1.0.6",

src/formatUnits.js

@@ -1,4 +1,4 @@
-const formatUnit = require('format-unit').default
+const { measureFrom } = require('measure-ts')
 const formatcoords = require('formatcoords')
 
 const defaults = {
@@ -11,20 +11,26 @@ let settings = defaults
 const distanceUnits = {
   si: ['cm', 'm', 'km'],
   imp: ['in', 'ft', 'yd', 'mi'],
-  nautical: 'M',
-  m: 'm'
+  nautical: ['M'],
+  m: ['m']
 }
 
 const areaUnits = {
   si: ['cm2', 'm2', 'ha', 'km2'],
-  imp: ['in2', 'ft2', 'yd2', 'ar', 'mi2'],
-  nautical: 'M2',
-  m: 'm2'
+  imp: ['in2', 'ft2', 'yd2', 'ac', 'mi2'],
+  nautical: ['M2'],
+  m: ['m2']
 }
 
 module.exports = {
-  distance: value => formatUnit('length')(value)(distanceUnits[global.options.formatUnitsSystem || defaults.system]),
-  area: value => formatUnit('area')(value)(areaUnits[global.options.formatUnitsSystem || defaults.system]),
+  distance: value => {
+    const measure = measureFrom.apply(this, distanceUnits[global.options.formatUnitsSystem || defaults.system])
+    return measure(value).toString()
+  },
+  area: value => {
+    const measure = measureFrom.apply(this, areaUnits[global.options.formatUnitsSystem || defaults.system])
+    return measure(value).toString()
+  },
   coord: value => formatcoords(value).format(global.options.formatUnitsCoordFormat || defaults.coordFormat, {
     latLonSeparator: global.options.formatUnitsCoordSpacer || defaults.coordSpacer
   }),