openfoodnetwork/spec/javascripts/services/variant_unit_manager_test.js

/**
 * @jest-environment jsdom
 */

import VariantUnitManager from "../../../app/webpacker/js/services/variant_unit_manager";

describe("VariantUnitManager", function() {
  let subject;

  describe("with default units", function() {
    beforeAll(() => {
      // Requires global var from page
      global.ofn_available_units_sorted = {
        "weight":{
          "1.0":{"name":"g","system":"metric"},"28.35":{"name":"oz","system":"imperial"},"453.6":{"name":"lb","system":"imperial"},"1000.0":{"name":"kg","system":"metric"},"1000000.0":{"name":"T","system":"metric"}
        },
        "volume":{
          "0.001":{"name":"mL","system":"metric"},"1.0":{"name":"L","system":"metric"},"1000.0":{"name":"kL","system":"metric"}
        },
      };
    })
    beforeEach(() => {
      subject = new VariantUnitManager();
    })

    describe("getUnitName", function() {
      it("returns the unit name based on the scale and unit type (weight/volume) provided", function() {
        expect(subject.getUnitName(1, "weight")).toEqual("g");
        expect(subject.getUnitName(1000, "weight")).toEqual("kg");
        expect(subject.getUnitName(1000000, "weight")).toEqual("T");
        expect(subject.getUnitName(0.001, "volume")).toEqual("mL");
        expect(subject.getUnitName(1, "volume")).toEqual("L");
        expect(subject.getUnitName(1000, "volume")).toEqual("kL");
        expect(subject.getUnitName(453.6, "weight")).toEqual("lb");
        expect(subject.getUnitName(28.35, "weight")).toEqual("oz");
      });
    });

    describe("compatibleUnitScales", function() {
      it("returns a sorted set of compatible scales based on the scale and unit type provided", function() {
        expect(subject.compatibleUnitScales(1, "weight")).toEqual([1.0, 1000.0, 1000000.0]);
        expect(subject.compatibleUnitScales(453.6, "weight")).toEqual([28.35, 453.6]);
        expect(subject.compatibleUnitScales(0.001, "volume")).toEqual([0.001, 1.0, 1000.0]);
      });
    });
  });

  describe("should only load available units", function() {
    beforeAll(() => {
      // Available units: "g,T,mL,L,kL,lb"
      global.ofn_available_units_sorted = {
        "weight":{
          "1.0":{"name":"g","system":"metric"},"453.6":{"name":"lb","system":"imperial"},"1000000.0":{"name":"T","system":"metric"}
        },
        "volume":{
          "0.001":{"name":"mL","system":"metric"},"1.0":{"name":"L","system":"metric"},"1000.0":{"name":"kL","system":"metric"}
        },
      };
    })
    beforeEach(() => {
      subject = new VariantUnitManager();
    })

    describe("compatibleUnitScales", function() {
      it("returns a sorted set of compatible scales based on the scale and unit type provided", function() {
        expect(subject.compatibleUnitScales(1, "weight")).toEqual([1.0, 1000000.0]);
        expect(subject.compatibleUnitScales(453.6, "weight")).toEqual([453.6]);
      });
    });
  });
});