d3.geoBounds is not working

[shrfarzk]

I stumbled upon an error while trying to use d3.geoBounds, and while trying to understand the cause of it I found something that is most likely a bug in area.js

Here's the part of the code I think is causing the error

export var areaRingSum;

var areaSum,
    lambda00,
    phi00,
    lambda0,
    cosPhi0,
    sinPhi0;

export var areaStream = {
  point: noop,
  lineStart: noop,
  lineEnd: noop,
  polygonStart: function() {
    areaRingSum.reset(); // <<< areaRingSum was never initialized
    areaStream.lineStart = areaRingStart;
    areaStream.lineEnd = areaRingEnd;
  },
  polygonEnd: function() {
    var areaRing = +areaRingSum;
    areaSum.add(areaRing < 0 ? tau + areaRing : areaRing);
    this.lineStart = this.lineEnd = this.point = noop;
  },
  sphere: function() {
    areaSum.add(tau);
  }
}

And here's the error

Cannot read property 'reset' of undefined
    at Object.areaStream.polygonStart (...\node_modules\d3-geo\build\d3-geo.js:169:18)
    at Object.boundsStream.polygonStart (...\node_modules\d3-geo\build\d3-geo.js:278:18)
    at streamPolygon (...\node_modules\d3-geo\build\d3-geo.js:143:12)
    at Object.streamGeometryType.MultiPolygon (...\node_modules\d3-geo\build\d3-geo.js:126:23)
    at streamGeometry (...\node_modules\d3-geo\build\d3-geo.js:88:40)
    at Object.streamObjectType.Feature (...node_modules\d3-geo\build\d3-geo.js:94:7)
    at geoStream (...\node_modules\d3-geo\build\d3-geo.js:150:36)
    at Object.bounds [as geoBounds] (...\node_modules\d3-geo\build\d3-geo.js:400:5)

I think it's worth noting that d3.geoCentroid and d3.geoLength all work on the same GeoJson object that causes the error when passed to d3.geoBounds

Also, d3.geoBounds returns [NaN, NaN] when a point is passed instead of a multipolygon, but I don't know the cause of this.

[mbostock]

Thanks for the report. I will look into it.

[mbostock]

Also, d3.geoBounds returns [NaN, NaN] when a point is passed instead of a multipolygon, but I don't know the cause of this.

Works fine for me:

d3.geoBounds({type: "Point", coordinates: [-123, 39]}) // [[-123, 39], [-123, 39]]

Please file a separate issue if you can demonstrate a bug in computing the bounds of points.