file-commons/src/utilities/File.test.ts

import * as fc from 'fast-check'
import File from './File'

jest.mock('./isBrowser', function IsBrowser() {
  return () => false
})

it('should exist', () => {
  expect(File).toBeDefined()
})

it('should be a callable', () => {
  expect(typeof File).toBe('function')
})

describe('instances', () => {
  it('should contain a name', () => {
    fc.assert(
      fc.property(
        fc.string().filter(s => /^[a-zA-Z0-9._-]+$/.test(s)),
        fileName => {
          const file = new File([], fileName, { type: 'application/octet-stream' })
          expect(file).toHaveProperty('name', fileName)
        }
      )
    )
  })

  it('should contain a last modified timestamp', () => {
    fc.assert(
      fc.property(
        fc.tuple(
          fc.string().filter(s => /^[a-zA-Z0-9._-]+$/.test(s)),
          fc.nat()
        ),
        ([fileName, lastModified]) => {
          const file = new File([], fileName, { type: 'application/octet-stream', lastModified })
          expect(file).toHaveProperty('lastModified', lastModified)
        }
      )
    )
  })

  it('should contain a type', () => {
    fc.assert(
      fc.property(
        fc.tuple(
          fc.oneof(
            fc.constant('application'),
            fc.constant('font'),
            fc.constant('audio'),
            fc.constant('model'),
            fc.constant('video'),
            fc.constant('text')
          ),
          fc.string().filter(s => /^[a-zA-Z0-9._-]+$/.test(s))
        ),
        mimeTypeFragments => {
          const file = new File([], 'foo', { type: mimeTypeFragments.join('/') })
          expect(file).toHaveProperty('type', mimeTypeFragments.join('/').toLowerCase())
        }
      )
    )
  })
})

describe('on cases for last modified date', () => {
  // We put lastModified as `any` because native DOM types classify
  // `lastModified` as number only under FilePropertyBag (but browser
  // accepts both Date and number objects equally.
  it('should be 0 given invalid date objects', () => {
    fc.assert(
      fc.property(
        fc.anything().filter(
          s =>
            // `new Date(Number.MAX_SAFE_INTEGER)` returns Invalid Date, but
            // is ok with File instances on browsers. Weird. This is why we
            // exclude numbers that will generate invalid dates (we already
            // covered numbers previously anyway).
            typeof s !== 'number' && isNaN(new Date(s as Date).getTime())
        ),
        v => {
          const lastModified = new Date(v as Date)
          const file = new File([], 'foo', { type: 'application/octet-stream', lastModified: lastModified as any })
          expect(file.lastModified).toBe(0)
        }
      )
    )
  })

  it('should be 0 given NaN', () => {
    const file = new File([], 'foo', { type: 'application/octet-stream', lastModified: NaN })
    expect(file.lastModified).toBe(0)
  })

  it('should be 0 given generic object values', () => {
    fc.assert(
      fc.property(fc.object(), o => {
        const file = new File([], 'foo', { type: 'application/octet-stream', lastModified: o as any })
        expect(file.lastModified).toBe(0)
      })
    )
  })

  it('should be a corresponding integer timestamp given valid date objects', () => {
    fc.assert(
      fc.property(fc.date(), lastModified => {
        const file = new File([], 'foo', { type: 'application/octet-stream', lastModified: lastModified as any })
        expect(file.lastModified).toBe(lastModified.getTime())
      })
    )
  })
})