next.js/test/unit/htmlescape.test.ts

/* eslint-env jest */
// These tests are based on https://github.com/zertosh/htmlescape/blob/3e6cf0614dd0f778fd0131e69070b77282150c15/test/htmlescape-test.js
// License: https://github.com/zertosh/htmlescape/blob/0527ca7156a524d256101bb310a9f970f63078ad/LICENSE
import { htmlEscapeJsonString } from 'next/dist/server/htmlescape'
import vm from 'vm'

describe('htmlescape', () => {
  test('with angle brackets should escape', () => {
    const evilObj = { evil: '<script></script>' }
    expect(htmlEscapeJsonString(JSON.stringify(evilObj))).toBe(
      '{"evil":"\\u003cscript\\u003e\\u003c/script\\u003e"}'
    )
  })

  test('with angle brackets should parse back', () => {
    const evilObj = { evil: '<script></script>' }
    expect(
      JSON.parse(htmlEscapeJsonString(JSON.stringify(evilObj)))
    ).toMatchObject(evilObj)
  })

  test('with ampersands should escape', () => {
    const evilObj = { evil: '&' }
    expect(htmlEscapeJsonString(JSON.stringify(evilObj))).toBe(
      '{"evil":"\\u0026"}'
    )
  })

  test('with ampersands should parse back', () => {
    const evilObj = { evil: '&' }
    expect(
      JSON.parse(htmlEscapeJsonString(JSON.stringify(evilObj)))
    ).toMatchObject(evilObj)
  })

  test('with "LINE SEPARATOR" and "PARAGRAPH SEPARATOR" should escape', () => {
    const evilObj = { evil: '\u2028\u2029' }
    expect(htmlEscapeJsonString(JSON.stringify(evilObj))).toBe(
      '{"evil":"\\u2028\\u2029"}'
    )
  })

  test('with "LINE SEPARATOR" and "PARAGRAPH SEPARATOR" should parse back', () => {
    const evilObj = { evil: '\u2028\u2029' }
    expect(
      JSON.parse(htmlEscapeJsonString(JSON.stringify(evilObj)))
    ).toMatchObject(evilObj)
  })

  test('escaped line terminators should work', () => {
    expect(() => {
      vm.runInNewContext(
        '(' +
          htmlEscapeJsonString(JSON.stringify({ evil: '\u2028\u2029' })) +
          ')'
      )
    }).not.toThrow()
  })
})