[Bug] Incorrect data for aria-label

[semla]

Version

5.5.0

Link to Minimal Reproduction

https://echarts.apache.org/examples/en/editor.html?c=candlestick-simple&code=PYBwLglsB2AEC8sDeAoWsCGAnCGBcSAptBgEYA2hAJnmFgK6EC-ANGrAB4CCHEAznmTt0VDGHywA2gHIATAAYAjAHYAtIvmrZAFmktYcpWo1aArHoMKV6zbIBsFw9ZOzl0gLrtW7AJ49-gkje6HyEOIQCUsJC6LGwYD4ghILSAMYY0FSUfJCpANZ60SJiEpJFsZIK-gDM2voaNQAc7mxxcZLa8jWmNV2wpvIt5eiS1YpNNdX62tpDbRXVjfU9_dOynvMbsUzsnkwA3EA

Steps to Reproduce

Look at the aria-label in the link.

Current Behavior

aria-label="This is a chart with type Candlestick.The data is as follows: the data for 2017-10-24 is 0, 20, 34, 10, 38, the data for 2017-10-25 is 1, 40, 35, 30, 50, the data for 2017-10-26 is 2, 31, 38, 33, 44, the data for 2017-10-27 is 3, 38, 15, 5, 42. "

an extra number is inserted before the correct data

Expected Behavior

aria-label="This is a chart with type Candlestick.The data is as follows: the data for 2017-10-24 is 20, 34, 10, 38, the data for 2017-10-25 is 40, 35, 30, 50, the data for 2017-10-26 is 31, 38, 33, 44, the data for 2017-10-27 is 38, 15, 5, 42. "

Environment

- OS:
- Browser:
- Framework:

Any additional comments?

Ran into it when working with 20038
Here is another example where the data for aria-label seems more confusing

[helgasoft]

Your code just enables aria without setting the label (?!)
Demo works.

<div id="chart-container" _echarts_instance_="ec_1719277587102" 
 aria-label="This is a chart with type Candlestick.The data is as follows: the data for 2017-10-24 is 0, 20, 34, 10, 38, the data for 2017-10-25 is 1, 40, 35, 30, 50, the data for 2017-10-26 is 2, 31, 38, 33, 44, the data for 2017-10-27 is 3, 38, 15, 5, 42. " 
 style="user-select: none; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);"><div style="position: relative; width: 501px; height: 575px; padding: 0px; margin: 0px; border-width: 0px; cursor: default;"><canvas data-zr-dom-id="zr_0" width="551" height="632" style="position: absolute; left: 0px; top: 0px; width: 501px; height: 575px; user-select: none; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); padding: 0px; margin: 0px; border-width: 0px;"></canvas></div>
</div>

📌 please close issue if problem solved.

[semla]

Your code just enables aria without setting the label (?!)

I am pretty sure the aria-label is generated if not set? What I was referring to was the data generated that seems incorrect.

[semla]

Seems like on some charts like bar, line, candlestick (not exhaustive list) each data item has an extra data point. It is the first one and seems like an index ("the data for Mon is 0, 1, the data for Tue is 1, -2,.. etc)

Here is a "naive" theory that maybe is useful?
I took a quick look at the code for the dataview in the toolbox, and it looks like there is a separation of chart-types:

echarts/src/component/toolbox/feature/DataView.ts

Lines 64 to 66 in a6d0463

	* Group series into two types
	* 1. on category axis, like line, bar
	* 2. others, like scatter, pie

In aria.ts it looks like it just returns the values from getData regardless of the type of chart:

echarts/src/visual/aria.ts

Line 207 in a6d0463

const data = seriesModel.getData();

[semla]

@Ovilia Are you sure it is not a bug?

[Ovilia]

Although I won't say this is the best thing we could do since the code in ARIA may be somewhat straightforward, I don't think this should be regarded as a bug. You may make a pull request to improve it.

#20038 tries to fix this by providing an option to let developers hide certain dimensions, while you could also change the default dimensions to display, like using the second instead of all in the case of candlestick series. Both plans solves the problem to some extent and it's either way works.

[semla]

Ok, yes #20038 should be usable to avoid the extra index data.

Here the data in aria-label is also repeated.

You may make a pull request to improve it.

Not sure I know enough but maybe I'll give it a shot. Is it a good idea to look at the code for the dataview ? iiuc that code deals differently with cartesian2D charts like lines, bar, candlestick - which seems to be the ones that are problematic