[XY] Percentiles with decimals do not work any more in visualize

[dej611]

Kibana version: 7.16.0

Describe the bug:

In Visualizes/Aggregation based visualizations percentile values do not work any more with decimals.

Percentile values like 1.5 or 99.5 used to work until 7.16.0, but now they are no longer: the current problem is probably relative no a missing column mapping in the final visualization code.

In percentiles column ids are matched with some string manipulation, which is probably going wrong this time.

As result the chart is removing the percentile column with decimals.

[elasticmachine]

Pinging @elastic/kibana-vis-editors @elastic/kibana-vis-editors-external (Team:VisEditors)

[flash1293]

Yep, seems like the logic here just splits by . which is not enough:

kibana/src/plugins/vis_types/xy/public/utils/accessors.tsx

Line 83 in 348bfb8

(columnId || '').toString().split('.')[0];

[flash1293]

@dej611 @stratoula While testing the fix, I noticed percentage mode on an axis doesn't work right as well for multi-value metrics - is this a known problem?

Like in this example:

Count metrics are respecting percentage mode, but percentiles don't. We don't have to fix it in the same PR necessarily, I can't think of a good use case to use percentage mode for percentile/percentile ranks, but still.

[stratoula]

@flash1293 yes this seems to be a bug of the normal mode. Stacked mode works correctly on my local branch. Do you want me to create an issue?