Increase the capability of the Sparkline

[hiromon0125]

Problem

Considering how small Sparkline is and not very meaningful in terms of holding information, this may not be very significant to many devs, but I was trying to use Sparkline to visually display workloads based on percentage value where there is an absolute range of values where the data range is static from 0 to 100.

However with the way that Sparkline is currently implemented, the range is dynamically determined based on the data list where the minimum and maximum bucket value is being used to display the range of values. Which only work for my case if there is always a bucket with the absolute minimum and maximum value in the data list, so I wanted to add a slight extension to the Sparkline component where I can set data range argument of two float tuple.

The reason I wanted this feature is that my data does not vary greatly to really make it meaningful to visualize using Sparkline because it will just flat line for majority of the time which is not very useful.

Solution

The logic for determining the minimum and maximum value can be found in renderable/sparkline.py line 92.

        # renderable/sparkline.py - line: 89-98
        bar_line_segments = len(self.BARS)
        bar_segments = bar_line_segments * height - 1

        minimum, maximum = min(self.data), max(self.data)
        extent = maximum - minimum or 1

        summary_function = self.summary_function
        min_color, max_color = self.min_color.color, self.max_color.color
        assert min_color is not None
        assert max_color is not None

I wanted to change this logic to contain the following:

        # renderable/sparkline.py - line: 89-98
        bar_line_segments = len(self.BARS)
        bar_segments = bar_line_segments * height - 1

        minimum, maximum = self.get_range()
        extent = maximum - minimum or 1

        summary_function = self.summary_function
        min_color, max_color = self.min_color.color, self.max_color.color
        assert min_color is not None
        assert max_color is not None

where the get_range method is the following:

        def get_range(self) -> tuple[T, T]:
            if self.range is not None:
                return self.range
            return min(self.data), max(self.data)

This retains the original behavior, if the range is None or not passed in, and allow me to statically set a range during initialization.
I can make a PR for this change if this is something I can add to the package and update the documentation around the Sparkline component.