Turf.js多边形合并（union）报non-noded intersection between错误的解决方案

问题

turf.js 是由Mapbox提供的一个控件分析库，非常适合WebGIS开发者使用，里面有丰富的空间分析与计算函数、数据转换函数。

最近在使用turf.js 进行多边形合并时，遇到一个问题如下，意思时多边形的两条线之间没有交点，但是后面跟的坐标全是在同一个多边形里面，自己怎么会跟自己没有交点呢？Polygon的数据格式肯定是没有问题的。

found non-noded intersection between LINESTRING ( 121.54630780220032 49.532520238303505, 121.54630780220032 49.53251675670836 ) and LINESTRING ( 121.54638290405273 49.532485  message: 'found non-noded intersection between LINESTRING ( 121.54630780220032 49.532520238303505, 121.54630780220032 49.53251675670836 ) and LINESTRING ( 121.54638290405273 49.532485
42234107, 121.54629707336426 49.532523719898364 )

解决方案

最后偶然发现，这个是turf.js版本的问题，出问题的版本是5.1.6 ，后台改为6.4.0 正常运行代码，没有任何问题

测试数据

[{"geometry": {"type": "Polygon","coordinates": 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"Feature","properties": {"zwdm": "54","zwmc": "旱地小麦"},"tile": {"z": 14,"x": 13723,"y": 5589}},{"geometry": {"type": "Polygon","coordinates": [[[121.54676377773285,49.53230437893674],[121.54676914215088,49.53230437893674],[121.54662430286407,49.53213377973054],[121.54662430286407,49.53213029810789],[121.5463238954544,49.531893547185746],[121.5463238954544,49.53189006554595],[121.54620587825775,49.53098134908848],[121.5463238954544,49.531893547185746],[121.54661893844604,49.53213726135294],[121.54676377773285,49.53230437893674]]]},"type": "Feature","properties": {"zwdm": "54","zwmc": "旱地小麦"},"tile": {"z": 14,"x": 13723,"y": 5589}}
]

测试代码

let fs = require('fs');
let  turf =require ('@turf/turf');let rawData = fs.readFileSync('data.json');
let polygons = JSON.parse(rawData);
let polygon=polygons[0]
for (let i = 1; i < polygons.length; i++) {console.log("循环"+i)polygon=turf.union(polygon,polygons[i])
}
console.log(polygon)