Inital add of lg functions with column logic

lib/_lg-logic.js

@@ -0,0 +1,15 @@
module.exports = {

  columnLogic: function(columnFraction, gutter, rounder) {
    let widthValue = '';
    let gutterLogic = '';

    if (gutter !== 0) {
      gutterLogic = ` - (${gutter} - ${gutter} * ${columnFraction})`;
    }

    widthValue = `calc(${rounder}% * ${columnFraction}${gutterLogic})`;
    return widthValue
  }

};

test/lg-logic.js

@@ -0,0 +1,22 @@
'use strict'

const expect = require('chai').expect;
const lgLogic = require('../lib/_lg-logic.js');


describe('columnLogic works as it should', () => {
  it('gutter and rounder ✅', () => {
    const foo = lgLogic.columnLogic('1/3', 30, 100);

    const expectedResult = `calc(100% * 1/3 - (30 - 30 * 1/3))`;

    expect(foo).to.equal(expectedResult);
  });
  it('no gutter ✅', () => {
    const foo = lgLogic.columnLogic('1/3', 0, 99.9);

    const expectedResult = `calc(99.9% * 1/3)`;

    expect(foo).to.equal(expectedResult);
  });
});