intersects bug Bezier to Bezier

[RGBWang]

new Bezier(50, 25, 50, 25, 122, 185, 111, 185);
var curve2 = new Bezier(9, 111, 8, 99, 136,78, 142, 58 );
var draw = function() {
  this.drawSkeleton(curve);
  this.drawCurve(curve);
  this.setColor("red");
  this.drawCurve(curve2);
  this.setColor("black");
  curve.intersects(curve2).forEach(pair => {
    var t = pair.split("/").map(v => parseFloat(v));
    this.drawPoint(curve.get(t[0]));
  });
}

[Pomax]

Don't just text-dump: please explain what's wrong, and how this code shows that off.

[RGBWang]

when copy the code in /docs/index.html ,

<script type="text/beziercode"> ,you can see the bug .two clearly intersecting lines, but not detected

[Pomax]

It looks like you've turned the black curve into a degenerate curve by overlapping its control point with its start point, which will indeed cause problems. The current solution is to make sure to work with "real" curves rather than degenerate ones, which in this case is simply moving the control point in the direction of the second control point by a small amount.