Candlestick chart won't render candlesticks while loading around 5000 - 10000 candles

Lightweight Charts Version: 3.1.5

Steps/code to reproduce: Easiest way to reproduce is to call candleStickSeries.setData([candles]) with 5000 - 10000 candles. I used the example from JSFiddle as base to reproduce this problem, making sure this isn’t a config problem on my end.

Actual behavior: Chart starts spamming "Value is null" errors in the developer console and won’t render the candlesticks.

Expected behavior: Longer wait time since the chart is loading a large amount of data, but render all the candlesticks.

Screenshots:

CodeSandbox/JSFiddle/etc link: https://jsfiddle.net/markverkiel/j3syf4dr/4/

[timocov]

Since this is currently breaking the chart, maybe it’s an idea to cancel the rendering and throw an error for duplicate time entries? Or throw a warning indicating that the data consist duplicate entries.

See #315

[matortheeternal]

I added some code to your fiddle to check if you had duplicate times in your data, and you do. The following times were duplicated:

["1593663300", "1593664200", "1593665100", "1593666000", "1593666900", "1593667800", "1593668700", "1593669600", "1593670500", "1593671400", "1593672300", "1593673200", "1593674100", "1593675000"]

Also your times aren’t integers, which is kind of weird, you should use Math.round to make them into whole numbers instead of floating point.

If you got your data via multiple requests you should make sure you don’t have overlap. You can sort, filter, and clean up your data for the time being if you don’t want to bother with re-fetching it. (if the data is sorted you only need to check if the previous item has the same time)