Fix transition for bs-collapse

[simonihmig]

Fixes #629, introduced by #746.

@jelhan fyi. I tried to add some tests, asserting that the height increases/decreases during the transition. Which kinda worked, but were quite flaky, so skipped them for now.

[jelhan]

Oh missed that one. Sorry.

I tried to add some tests, asserting that the height increases/decreases during the transition. Which kinda worked, but were quite flaky, so skipped them for now.

I guess related to hard-coded duration of 0ms in testing? https://github.com/kaliber5/ember-bootstrap/blob/v2.5.0/addon/utils/transition-end.js#L11-L13 That makes asserting interim states difficult, isn't it?

[simonihmig]

I guess related to hard-coded duration of 0ms in testing? https://github.com/kaliber5/ember-bootstrap/blob/v2.5.0/addon/utils/transition-end.js#L11-L13 That makes asserting interim states difficult, isn't it?

Yeah, with that 0ms it obviously didn't work at all. But I played with a function to override this duration in tests, but even when setting this to the original 350ms, it wasn't working reliably. And it wasn't debuggable, as setting any breakpoint during the transition didn't allow to inspect what was going on, as the CSS transition wasn't stopped obviously. It was working like in 80% of the test runs, but failing without an obvious reason in the other ones... 🙄

[simonihmig]

Oh missed that one. Sorry.

No problem at all! 🙂