Time Axis: tooltipFormat does not work

[robske110]

Expected Behavior

tooltipFormat property of options.xAxes[0].time should change the tooltip title correctly.

Current Behavior

When tooltipFormat is specified, tooltips are not displayed and the following error is displayed in console:
Error: fromMillis requires a numerical input, but received a object with value null

Possible Solution

correctly use content of labels array

Steps to Reproduce

Create a chart with a time axis and try to use tooltipFormat.
https://jsfiddle.net/0yhmsrwf/

Context

Trying to use tooltipFormat to display a detailed timestamp at the top of the tooltip

Environment

• Chart.js version: 2.9.4
• Browser name and version: Safari 14.0.3 (14610.4.3.1.6)

[kurkle]

Works with {x, y} or {t, y} data: https://jsfiddle.net/o2p4et87/

[robske110]

Has anyone found out why this is happening? Since the workaround by @kurkle works, I assume this is because the labels array contents are not correctly correlated to the ticks.

[gusbemacbe]

@robske110, @kurkle and @etimberg.

The tooltimpForm does not work yet even in the latest version. Remember I do not Node/NPM, I use the CSV and date-fns.

I used tooltipFormat to hide the unnecessary hour. Check my JSFiddle: https://jsfiddle.net/gusbemacbe/dezy7cow/4/

Try to touch one bar of the first graph due to tooltipFormat.

Observe that adapters: { locale: "pt" } inside options does not work either.

[kurkle]

@gusbemacbe you are loading data from CSV, but it is transformed to a JS array, so that part is external and does not concern Chart.js in any way.

In your first chart, the tooltipFormat is incorrect for date-fns:

Uncaught RangeError: Use yyyy instead of YYYY (in dd/MM/YYYY) for formatting years to the input 1613606400000; see: https://git.io/fxCyr

After fixing that:

I'm not sure why you think adapters: { locale: "pt" } should work. There is an proper example on the chartjs-adapter-date-fns README:
https://github.com/chartjs/chartjs-adapter-date-fns#locale-support-via-scale-options

[gusbemacbe]

'm not sure why you think adapters: { locale: "pt" } should work. There is an proper example on the chartjs-adapter-date-fns README:
https://github.com/chartjs/chartjs-adapter-date-fns#locale-support-via-scale-options

I do not use Node or Reactjs. My JavaScript file is not a module. I also tried adapters: {date: { locale: "pt" }} inside options.

I want to translate the months names into another language.