Axis order not correctly extracted from EPSG:4326

[SimonBin]

using this definition from gdalsrsinfo:

gdalsrsinfo -o wkt1 EPSG:4326

GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0,
        AUTHORITY["EPSG","8901"]],
    UNIT["degree",0.0174532925199433,
        AUTHORITY["EPSG","9122"]],
    AXIS["Latitude",NORTH],
    AXIS["Longitude",EAST],
    AUTHORITY["EPSG","4326"]]

we can see the axis order is NE (lat/long) however wkt-parser fails to extract it:

wkt(epsg4326)

{
  type: 'GEOGCS',
  name: 'WGS 84',
  DATUM: {
    name: 'WGS_1984',
    SPHEROID: {
      name: 'WGS 84',
      a: 6378137,
      rf: 298.257223563,
      AUTHORITY: [Object]
    },
    AUTHORITY: { EPSG: '6326' }
  },
  PRIMEM: { name: 'greenwich', convert: 0, AUTHORITY: { EPSG: '8901' } },
  UNIT: {
    name: 'degree',
    convert: 0.0174532925199433,
    AUTHORITY: { EPSG: '9122' }
  },
  AXIS: [ [ 'Latitude', 'NORTH' ], [ 'Longitude', 'EAST' ] ],
  AUTHORITY: { EPSG: '4326' },
  projName: 'longlat',
  units: 'degree',
  to_meter: 111319.4907932736,
  datumCode: 'wgs84',
  ellps: 'WGS 84',
  a: 6378137,
  rf: 298.257223563,
  srsCode: 'WGS 84'
}

the missing axis key then later on lets proj4js set axis: 'enu'

https://github.com/proj4js/proj4js/blob/a8bdc85b7c5804d0c05d99c95a8c165287c3c362/lib/Proj.js#L38

  json.axis = json.axis || 'enu';

resulting in a mess

[ahocevar]

proj4js does not really make use of the axis property, unless you use it like described here. Is that what you're doing? If so, would you be able to sumit a pull request to add support for axis in wkt-parser?

[SimonBin]

I can do it by relaxing the check like this:

diff --git a/index.js b/index.js
index 7cd2316..bc186b2 100644
--- a/index.js
+++ b/index.js
@@ -36,13 +36,13 @@ function cleanWKT(wkt) {
       var axisOrder = '';
     for (var i = 0, ii = wkt.AXIS.length; i < ii; ++i) {
        var axis = [wkt.AXIS[i][0].toLowerCase(), wkt.AXIS[i][1].toLowerCase()];
-      if (axis[0].indexOf('north') !== -1 || ((axis[0] === 'y' || axis[0] === 'lat') && axis[1] === 'north')) {
+       if (axis[0].indexOf('north') !== -1 || ((axis[0] === 'y' || axis[0].indexOf('lat') !== -1) && axis[1] === 'north')) {
           axisOrder += 'n';
-      } else if (axis[0].indexOf('south') !== -1 || ((axis[0] === 'y' || axis[0] === 'lat') && axis[1] === 'south')) {
+      } else if (axis[0].indexOf('south') !== -1 || ((axis[0] === 'y' || axis[0].indexOf('lat') !== -1) && axis[1] === 'south')) {
         axisOrder += 's';
-      } else if (axis[0].indexOf('east') !== -1 || ((axis[0] === 'x' || axis[0] === 'lon') && axis[1] === 'east')) {
+      } else if (axis[0].indexOf('east') !== -1 || ((axis[0] === 'x' || axis[0].indexOf('lon') !== -1) && axis[1] === 'east')) {
         axisOrder += 'e';
-      } else if (axis[0].indexOf('west') !== -1 || ((axis[0] === 'x' || axis[0] === 'lon') && axis[1] === 'west')) {
+      } else if (axis[0].indexOf('west') !== -1 || ((axis[0] === 'x' || axis[0].indexOf('lon') !== -1) && axis[1] === 'west')) {
         axisOrder += 'w';
       }
     }

or by entirely removing the ((axis[0] === '?' || axis[0] === '???') && check

but the question is why the code is done like it is now

[ahocevar]

I'd rather do axis[0].startsWith('lat') instead of axis[0].indexOf('lat') !== -1, but other than that the change makes sense.