[polskibus]

I have really bad experience using controls that didn't have a large test suite. They don't have to be "unit" , I just care about the ratio of the number of state transitions it tests to possible state transitions. If that library was written in typescript (or some other strongly typed language), I'd been slightly less worried about the lack of tests, and possibly slightly more convinced to try it out in its early stage.

[rinchik]

I agree, unit tests wouldn't be very useful here, i was thing that visual regression tests with constant data, that capture graph image and compare with older version for regressions would have been really nice here.

[polskibus]

As a side note: I find these kind of tests flaky, because the antialiasing doesn't seem stable at constant resolution on the same machine & browsers when you repeat tests. When you do a fuzzy compare (ie. allow for X pixels difference), then you are always chasing the golden middle. A test I would like to see for a control is trigger multiple state transitions (for example change 5 properties of a chart), do assertions on the generated DOM.

Unless maybe some HNer knows how to do such SVG/picture testing non flaky?