Bug: using "not in" operator in switch works as "in" instead

[hendricha]

switch
  when thing in arr
    console.log 'this'
  when thing not in arr
    console.log 'that'

Expected Behavior

The above should probably compile to something along the lines of this:

var indexOf = [].indexOf;

switch (false) {
  case indexOf.call(arr, thing) < 0:
    console.log('this');
    break;
  case indexOf.call(arr, thing) >= 0:
    console.log('that');
}

Current Behavior

It however compiles to this:

var indexOf = [].indexOf;

switch (false) {
  case indexOf.call(arr, thing) < 0:
    console.log('this');
    break;
  case indexOf.call(arr, thing) < 0:
    console.log('that');
}

Environment

• CoffeeScript version: 2.7.0
• Node.js version: some version of 14 for legacy reasons
  But the thing happens even on the "try coffeescript" page on the website too

Other context

This does not happen in coffee v1 nor in civet with coffee compat