Consider a way to support/add equalJSX method

[MoOx]

I am currently using tape and I am considering switching to AVA.
There is just one piece missing atm: https://github.com/atabel/tape-jsx-equals
As you can see tape-jsx-equals use extend-tape to extends tape.
Are you open to add support of equalJSX in the core? If not will it be possible to provide a way to easily extends AVA?

[MoOx]

Note: this is assertion is doable using https://github.com/algolia/react-element-to-jsx-string

[MoOx]

Also please note that another method is really handy when testing react component: includeJSX. This one ignore whitespace differences which can be very handy.

[jamestalmage]

@MoOx The ability to add custom assertions is on the roadmap.

[sindresorhus]

You can already use any custom assertion. The only minus is that assertion counting doesn't work. We plan to add support for adding custom assertions. See #49.

[MoOx]

FYI, here is how I do for now

import "babel-core/register"
import test from "ava"

import React, { Component } from "react"
import { createRenderer } from "react-addons-test-utils"
// import ReactDOMServer from "react-dom/server"
import expect from "expect"
import expectJSX from "expect-jsx"
expect.extend(expectJSX)

import MyComponent from ".."

test("MyComponent default render", (t) => {
  const renderer = createRenderer()

  renderer.render(
    <MyComponent />
  )
  expect(
    renderer.getRenderOutput()
  )
  .toEqualJSX(
    <div />
  )
})

Result

❯ npm run ava

> ~@ ava ~
> ava "web_modules/**/__tests__/*.js"


  ✖ MyComponent default render Expected '<div>\n  <div className="container-navigation-list" />\n</div>' to equal '<div />'

  1 test failed

  1. MyComponent default render
  Error: Expected '<div>\n  <div className="container-navigation-list" />\n</div>' to equal '<div />'
    at Object.assert [as default] (~/node_modules/expect/lib/assert.js:20:9)
    at Expectation.toEqual (~/node_modules/expect/lib/Expectation.js:69:26)
    at Expectation.toEqualJSX (~/node_modules/expect-jsx/index-dist.js:27:93)
    at Test.fn (~/web_modules/Portal/__tests__/index.js:40:56)
    at tryCatcher (~/node_modules/bluebird/js/release/util.js:11:23)
    at Object.gotValue (~/node_modules/bluebird/js/release/reduce.js:145:18)
    at Object.gotAccum (~/node_modules/bluebird/js/release/reduce.js:134:25)
    at Object.tryCatcher (~/node_modules/bluebird/js/release/util.js:11:23)
    at Promise._settlePromiseFromHandler (~/node_modules/bluebird/js/release/promise.js:489:31)
    at Promise._settlePromise (~/node_modules/bluebird/js/release/promise.js:546:18)
    at Promise._settlePromiseCtx (~/node_modules/bluebird/js/release/promise.js:583:10)
    at Async._drainQueue (~/node_modules/bluebird/js/release/async.js:134:12)
    at Async._drainQueues (~/node_modules/bluebird/js/release/async.js:139:10)
    at Immediate.Async.drainQueues [as _onImmediate] (~/node_modules/bluebird/js/release/async.js:16:14)

[novemberborn]

Let's continue discussion in #446. Any future improvements will benefit from our solution to #25.