test.js

require('jsdom-global')()
const assert = require('assert')
const viewport = require('./')

const notNaN = v => !isNaN(v)

describe('Bianco viewport', function() {
  it('export default contains all the module methods', function() {
    assert.deepEqual(Object.keys(viewport.default), [
      'scrollbarWidth',
      'documentHeight',
      'documentWidth',
      'scrollTop',
      'scrollLeft',
      'elementOffsetTop',
      'elementOffsetLeft'
    ])
  })

  it('scrollbarWidth is a number', function() {
    assert.equal(typeof viewport.scrollbarWidth(), 'number')
    assert.ok(notNaN(viewport.scrollbarWidth()))
  })

  it('documentHeight is a number', function() {
    assert.equal(typeof viewport.documentHeight(), 'number')
    assert.ok(notNaN(viewport.documentHeight()))
  })

  it('documentWidth is a number', function() {
    assert.equal(typeof viewport.documentWidth(), 'number')
    assert.ok(notNaN(viewport.documentWidth()))
  })

  it('scrollTop is a number', function() {
    assert.equal(typeof viewport.scrollTop(), 'number')
    assert.ok(notNaN(viewport.scrollTop()))
  })

  it('scrollLeft is a number', function() {
    assert.equal(typeof viewport.scrollLeft(), 'number')
    assert.ok(notNaN(viewport.scrollLeft()))
  })

  it('elementOffsetTop is a number', function() {
    const div = document.createElement('div')
    assert.equal(typeof viewport.elementOffsetTop(div), 'number')
    assert.ok(notNaN(viewport.elementOffsetTop(div)))
  })

  it('elementOffsetLeft is a number', function() {
    const div = document.createElement('div')
    assert.equal(typeof viewport.elementOffsetLeft(div), 'number')
    assert.ok(notNaN(viewport.elementOffsetLeft(div)))
  })
})