code coverage (nyc - Istanbul's cli) fail with rewire and mocha version >3

[GalNoga]

when upgrading to mocha >3 rewire ruins the code coverge generate by nyc. all works well without using rewire..
node version: 10.15.2
rewire: 4.0.1
nyc: 13.3.0
mocha: works with '3.5.3', fail with ^4,^5,^6
OS: windows, Darwin
command: "nyc --reporter=html --reporter=text ./node_modules/.bin/mocha "./*.spec.js" --timeout=3000"

works with mocha '3.5.3':

fail with mocha ^4,^5,^6:

[jhnns]

Can you provide a minimal test case? I'm using nyc + mocha in my tests and there doesn't seem to be an issue.