Have an actual assertion against `true` and discourage the use of `truthy`

[jkrems]

truthy is a very dangerous convenience. There's a lot of values that are truthy but not true and a truthy test basically just checks that it's anything. It's way too easy to write tests that "pass by accident" when using truthy.

[EndangeredMassa]

I agree. The "pass by accident" issue is real.

Did you intend to say to use "equal" over "truthy"?

[jkrems]

If possible equal is better than either, yes. But for things like x > 10 or just a precalculated x, expect would still be better than truthy. The following code is inspired by a testium issue: groupon/testium#144

truthy 'is visible', @browser.evaluate ->
  throw new Error 'Something goes terribly wrong'
  $('.missing-element').is(':visible') # actually returns false

The above passes because the result of a failing evaluate happens to be "truthy" - but not true. expect would have properly caught it.

Aaaactually I just saw that expect does not check for equality with true but also only for "truthy". I'm going to change the title of this issue to "assertive should have a way to actually assert with a hard test against true".

[jkrems]

I'd love if expect would change to mean "argument is exactly true". Might require a major bump but I think it'd be worth it.

[johan]

I love this idea. It also neatly addresses the somewhat embarrassing expect function whose use I have been discouraging, while keeping it for some kind of assert library easy porting compat, despite disliking how its fast-and-loose-ness made it impossible to use with the docstring arg all other assertive calls take.

Forcing it to take boolean true alone solves everything. :-) Totally worth doing with a major bump.