import * as Units from "..";
import { Measure } from "../../measure/numberMeasure";

describe("Predefined units", () => {
  const UnitNames = Object.keys(Units);
  const lowercaseFirstRegex = /^[a-z]/;

  function forEachUnit(fn: (unit: Measure<any>, name: string) => void): void {
    const wrappedCallback = (value: any, name: string) => {
      // Quantities start with a capital letter, exclude them
      if (Measure.isMeasure(value) && lowercaseFirstRegex.test(name)) {
        fn(value, name);
      }
    };

    UnitNames.forEach((name) => {
      const value = (Units as any)[name];
      if (Measure.isMeasure(value)) {
        wrappedCallback(value, name);
      } else {
        for (const subName in value) {
          if (value.hasOwnProperty(subName)) {
            const unit = value[subName];
            wrappedCallback(unit, subName);
          }
        }
      }
    });
  }

  it("all units should have a symbol", () => {
    forEachUnit((unit, name) => {
      try {
        expect(unit.symbol).not.toBeUndefined();
      } catch (e) {
        console.log(`Unit ${name} has no symbol defined.`);
        throw e;
      }
    });
  });
});