Style empty points in line charts via CSS

[gcmznt]

moved point color from fill to color to let the possibility to use the color for stroke via css like:

  .c3-circle {
    fill: white;
    stroke: currentColor;
    stroke-width: 2px;
  }

[codecov-io]

Codecov Report

Merging #1992 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1992   +/-   ##
=======================================
  Coverage   64.09%   64.09%           
=======================================
  Files           1        1           
  Lines        4406     4406           
=======================================
  Hits         2824     2824           
  Misses       1582     1582

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[stephencookdev]

+1, would really like to see this in the codebase

For anyone else landing here from Googling around, I'm currently doing the following hack to achieve a similar result to what this PR would provide:

import c3 from "c3";

const originalRedrawCircle = c3.chart.internal.fn.redrawCircle;
const originalUpdateCircle = c3.chart.internal.fn.updateCircle;
c3.chart.internal.fn.redrawCircle = function() {
  const response = originalRedrawCircle.apply(this, arguments);
  const mainCircle = response[0];
  mainCircle.style("color", this.color);
  return response;
};
c3.chart.internal.fn.updateCircle = function() {
  const response = originalUpdateCircle.apply(this, arguments);
  this.mainCircle.style("color", this.color);
  return response;
};

[panthony]

An up to date version exists here #2693