How to test concurrent rendering?

[kuraga]

@Raynos @neonstalwart @Matt-Esch How to test concurrent rendering?

Question is similar to testing of main-loop: http://stackoverflow.com/questions/34862892/test-concurrent-call-of-the-same-function

See, please! Thanks!

[yoshuawuyts]

@kuraga I'm sorry, I still have no idea what you mean? What do you expect to test?

Because raf ticks asynchronously you can execute unit tests in between tests to assert values; just wrap the tests themselves in raf calls to make them execute on the same tick. Does that answer your question?

[kuraga]

@yoshuawuyts big thanks for reading and reply!

I want to test that "render call delays longAction call until current render ends". Every man says "async" but means different 😄

var value = 0;
raf(function () {
  console.log(value);  // logs: 12345678
});
for(; value < 12345678; ++value);

So I can't (without some magic I ask about) start render during render...