Add US imperial

app/static/app/js/classes/Units.js

@@ -2,15 +2,25 @@ import { _ } from './gettext';
 
 const units = {
     acres: {
-      factor: 1 / 4046.85642,
-      abbr: 'ac',
+        factor: (1 / (0.3048 * 0.3048)) / 43560,
+        abbr: 'ac',
+        round: 5
+    },
+    acres_us: {
+      factor: Math.pow(3937 / 1200, 2) / 43560,
+      abbr: 'ac (US)',
       round: 5
     },
     feet: {
-      factor: 3.28084,
+      factor: 1 / 0.3048,
       abbr: 'ft',
       round: 4
     },
+    feet_us:{
+      factor: 3937 / 1200,
+      abbr: 'ft (US)',
+      round: 4
+    },
     hectares: {
       factor: 0.0001,
       abbr: 'ha',
@@ -32,15 +42,25 @@ const units = {
       round: 1
     },
     miles: {
-      factor: 3.28084 / 5280,
-      abbr: 'mi',
-      round: 5
+        factor: (1 / 0.3048) / 5280,
+        abbr: 'mi',
+        round: 5
+      },
+    miles_us: {
+        factor: (3937 / 1200) / 5280,
+        abbr: 'mi (US)',
+        round: 5
     },
     sqfeet: {
-      factor: 1 / 0.09290304,
+      factor: 1 / (0.3048 * 0.3048),
       abbr: 'ft²',
       round: 2
     },
+    sqfeet_us: {
+        factor: Math.pow(3937 / 1200, 2),
+        abbr: 'ft² (US)',
+        round: 2
+    },
     sqmeters: {
       factor: 1,
       abbr: 'm²',
@@ -52,9 +72,14 @@ const units = {
         round: 5
     },
     sqmiles: {
-      factor: 0.000000386102,
+      factor: Math.pow((1 / 0.3048) / 5280, 2),
       abbr: 'mi²',
       round: 5
+    },
+    sqmiles_us: {
+        factor: Math.pow((3937 / 1200) / 5280, 2),
+        abbr: 'mi² (US)',
+        round: 5
     }
 };
 
@@ -117,24 +142,71 @@ class ImperialSystem extends UnitSystem{
     getName(){
         return _("Imperial");
     }
+
+    feet(){
+        return units.feet;
+    }
+
+    sqfeet(){
+        return units.sqfeet;
+    }
+
+    miles(){
+        return units.miles;
+    }
+
+    sqmiles(){
+        return units.sqmiles;
+    }
+
+    acres(){
+        return units.acres;
+    }
     
     lengthUnit(meters){
-        const feet = units.feet.factor * meters;
-        if (feet >= 5280) return units.miles;
-        else return units.feet;
+        const feet = this.feet().factor * meters;
+        if (feet >= 5280) return this.miles();
+        else return this.feet();
     }
 
     areaUnit(sqmeters){
-        const sqfeet = units.sqfeet.factor * sqmeters;
-        if (sqfeet >= 43560 && sqfeet < 27878400) return units.acres;
-        else if (sqfeet >= 27878400) return units.sqmiles;
-        else return units.sqfeet;
+        const sqfeet = this.sqfeet().factor * sqmeters;
+        if (sqfeet >= 43560 && sqfeet < 27878400) return this.acres();
+        else if (sqfeet >= 27878400) return this.sqmiles();
+        else return this.sqfeet();
+    }
+}
+
+class ImperialUSSystem extends ImperialSystem{
+    getName(){
+        return _("Imperial (US)");
+    }
+
+    feet(){
+        return units.feet_us;
+    }
+
+    sqfeet(){
+        return units.sqfeet_us;
+    }
+
+    miles(){
+        return units.miles_us;
+    }
+
+    sqmiles(){
+        return units.sqmiles_us;
+    }
+
+    acres(){
+        return units.acres_us;
     }
 }
 
 const systems = {
     metric: new MetricSystem(),
-    imperial: new ImperialSystem()
+    imperial: new ImperialSystem(),
+    imperialUS: new ImperialUSSystem()
 }
 
 // Expose to allow every part of the app to access this information

app/static/app/js/components/tests/Units.test.jsx

@@ -41,34 +41,38 @@ describe('Metric system', () => {
   })
 });
 
-describe('Imperial system', () => {
+describe('Imperial systems', () => {
   it('it should display units properly', () => {
 
-    const { imperial } = systems;
+    const { imperial, imperialUS } = systems;
 
     const lengths = [
-        [1, "3.2808 ft"],
-        [0.01, "0.0328 ft"],
-        [0.0154, "0.0505 ft"],
-        [1609, "5,278.8716 ft"],
-        [1609.344, "1 mi"],
-        [3218.69, "2 mi"]
+        [1, "3.2808 ft", "3.2808 ft (US)"],
+        [0.01, "0.0328 ft", "0.0328 ft (US)"],
+        [0.0154, "0.0505 ft", "0.0505 ft (US)"],
+        [1609, "5,278.8714 ft", "5,278.8608 ft (US)"],
+        [1609.344, "1 mi", "5,279.9894 ft (US)"],
+        [1609.3472187, "1 mi", "1 mi (US)"],
+        [3218.69, "2 mi", "2 mi (US)"]
     ];
     
     lengths.forEach(l => {
-        expect(imperial.length(l[0]).toString()).toBe(l[1]);
+      expect(imperial.length(l[0]).toString()).toBe(l[1]);
+      expect(imperialUS.length(l[0]).toString()).toBe(l[2]);
     });
 
     const areas = [
-        [1, "10.76 ft²"],
-        [9999, "2.47081 ac"],
-        [4046.86, "1 ac"],
-        [2587398.1, "639.35999 ac"],
-        [2.59e+6, "1 mi²"]
+        [1, "10.76 ft²", "10.76 ft² (US)"],
+        [9999, "2.47081 ac", "2.4708 ac (US)"],
+        [4046.86, "1 ac", "43,559.86 ft² (US)"],
+        [4046.87261, "1 ac", "1 ac (US)"],
+        [2587398.1, "639.35999 ac", "639.35744 ac (US)"],
+        [2.59e+6, "1 mi²", "1 mi² (US)"]
     ];
 
     areas.forEach(a => {
-        expect(imperial.area(a[0]).toString()).toBe(a[1]);
+      expect(imperial.area(a[0]).toString()).toBe(a[1]);
+      expect(imperialUS.area(a[0]).toString()).toBe(a[2]);
     });
   })
 });