How to prevent ava displaying long objects when a test fails

Question

Given: Express app, AVA, supertest

When: I test generated html in response and the test case fails

Then: AVA displays the whole response object in the console which slows down analysis of the issue

Example of the test:

test('Positive case: book is found in /api/v1/books/1', async (t) => {
  t.plan(2)
  const response = await request(app).get('/api/v1/books/1')
  t.is(response.status, 200)
  const expectedBook = '<h3>Book 1</h3>'
  t.truthy(response.res.text.match(expectedBook), 'Book title is not found')
})

Example of the output in the console

/express-project/src/books/index.test.js:22

   21:   const text = response.res.text
   22:   t.truthy(response.res.text.match(expectedBook), 'Book t…
   23:   })

  Book title is not found

  Value is not truthy:

  null

  response.res.text.match(expectedBook)
  => null

  expectedBook
  => '<h3>Book 2</h3>'

  response.res.text
  => '<!DOCTYPE html><html><head><title>BOOK</title><link rel="stylesheet" href="/stylesheets/style.css"></head><body><h1>BOOK</h1>
<h3>Book 1</h3><h4></h4></body></html>'

  response.res
  => IncomingMessage {
    _consuming: false,
    _dumped: false,
    _events: {
      close: Function bound emit {},
      data: [
        Function {},
        Function {},
        Function bound emit {},
      ],
      end: [
        Function responseOnEnd {},
        Function {},
        Function bound emit {},
      ],
      error: [
        Function bound onceWrapper { … },
        Function bound emit {},
      ],
    },
    _eventsCount: 4,
    _maxListeners: undefined,
    _readableState: ReadableState [
      awaitDrain: 0,

    ..........  VERY LONG LIST WITH HUNDREDS OF LINES
    SO HAVE TO SCROLL UP AND UP AND UP BEFORE YOU GET TO THE POINT

score 1 · Answer 1 · answered May 13 '18 at 10:16

Ava is trying to be helpful in debugging the failed test so Ava puts in the console respectively

response.res.text
response.res
response

and it generates hundreds of even thousands of lines in the console

So the solution is pretty simple - use an intermediate variable for the assertion

Instead of

t.truthy(response.res.text.match(expectedBook), 'Book title is not found')

use

const text = response.res.text
t.truthy(text.match(expectedBook), 'Book title is not found')

How to prevent ava displaying long objects when a test fails

1 Answers1