Inconsistency when setting `tickvals` and omitting `ticktext` in date axes

[stakemura]

Please see https://jsfiddle.net/0cjprqgy/10/
All ticks of date axis display as "hh:mm:ss aN".

[etpinard]

That's probably because your tickvals aren't valid date timestamps.

How did you get those values?

[stakemura]

In real use case, I used programmaticaly-generated date timestamps.
However, all cases seemed to be failed.
OK. the following new sample use apparently valid timestamps.
How about https://jsfiddle.net/0cjprqgy/11/ ?

[etpinard]

Looks like those weird tick labels are caused by you not providing a ticktext setting to accompany tickvals. Setting a proper ticktext makes your problem go away http://codepen.io/etpinard/pen/YWEdJX .

But, those weird labels do showcase an inconsistency between linear and date axis types. See http://codepen.io/etpinard/pen/rLYoqK here omitting to provide ticktext falls back to stringnified tickvals values - making this issue a very low priority bug.

Maybe a better question to ask ourselves: should we allow tickmode: 'array' when tickvals isn't provided? I'm changing the issue title to reflect this. Thanks.

[stakemura]

Thank you for your consideration.
I tried tickvals with ticktext actually but I found the different problem.
Like http://codepen.io/etpinard/pen/YWEdJX , hover text won't be able to show date.
I guess hover text on date axis show date and time fundamentally.
What makes this difference?

[etpinard]

hover text won't be able to show date.

You mean it only shows the hour? Interesting. Thanks for pointing this out. This is probably related to the inconsistency mentioned in #738 (comment)

[stakemura]

Without tickvals date axis shows date and time apparently.
Please check https://jsfiddle.net/0cjprqgy/12/ .

[etpinard]

Without tickvals date axis shows date and time apparently

Yeah I noticed that too. This should be resolved in the same patch as for #738 (comment)

Thanks.