null values are being treated as zeros in LineChart

I am submitting a…

• Feature request
• Design defect
• Source code defect
• Demo/documentation defect
• Other

charts version:

0.16.25

Issue description

If I pass null values to a LineChart, instead of getting gaps in the data, the graph graphs the value as a 0 on the y-axis.

Steps to produce the issue

{
					date: new Date(2019, 0, 1),
					value: 10000
				},
				{
					date: new Date(2019, 0, 1),
					value: null
				},

Current behavior

Graphs as zeros

Expected behavior

I’m expecting something a little like this: https://www.carbondesignsystem.com/data-visualization/axes-and-labels/#gaps-in-data

Screenshot or recording

[anne-stevens]

Nulls should not be rendered as zeros. A zero is an actual value that a user, sensor or system acutally input. A null the absence of a value. It is conceptually very different than zero. In the line chart example, nulls should simply not be plotted.

[theiliad]

Closed by #464