Question on coverage

[ralphtheninja]

So, given the current state we have the following results:

I want to write a test that covers the following line

codec/index.js

Line 97 in 63d29a5

return function () {}

So I add the following test:

  t.test('no keys and no values not decoding', function (t) {
    var decoder = codec.createStreamDecoder({})
    t.equal(decoder(null, Buffer.from('hey')), undefined)
    t.equal(decoder(Buffer.from('hey')), undefined)
    t.end()
  })

The test works (passes) and covers the line correctly. However, for some reason nyc reports new lines in the code that aren't covered, which seems a bit weird to me. How can adding an extra test remove coverage? At worst it it's a bad test that doesn't add coverage, but it should never remove coverage imo. See below:

What's going on here?

[vweevers]

Perhaps those lines are partially covered, and your test changes the balance of how many times certain code branches are hit.

nyc report --reporter=html could tell you more.

[ralphtheninja]

Also, there's seem to be a difference between red lines and yellow lines. Not sure what the color coding here means.

nyc report --reporter=html could tell you more.

Cool, will check it out.