Transform without axis order in proj4

src/ol/proj/proj4.js

@@ -8,6 +8,7 @@ import {
   addProjection,
   get,
 } from '../proj.js';
+import {assign} from '../obj.js';
 import {get as getTransform} from './transforms.js';
 
 /**
@@ -46,10 +47,16 @@ export function register(proj4) {
       const code2 = projCodes[j];
       const proj2 = get(code2);
       if (!getTransform(code1, code2)) {
-        if (proj4.defs[code1] === proj4.defs[code2]) {
+        const def1 = proj4.defs(code1);
+        const def2 = proj4.defs(code2);
+        if (def1 === def2) {
           addEquivalentProjections([proj1, proj2]);
         } else {
-          const transform = proj4(code1, code2);
+          // Reset axis because OpenLayers always uses x, y axis order
+          const transform = proj4(
+            assign({}, def1, {axis: undefined}),
+            assign({}, def2, {axis: undefined})
+          );
           addCoordinateTransforms(
             proj1,
             proj2,

test/spec/ol/proj.test.js

@@ -728,6 +728,20 @@ describe('ol.proj', function () {
       clearAllProjections();
       addCommon();
     });
+
+    it('does not flip axis order', function () {
+      proj4.defs('enu', '+proj=longlat');
+      proj4.defs('neu', '+proj=longlat +axis=neu');
+      register(proj4);
+
+      const got = transform([1, 2], 'neu', 'enu');
+      expect(got).to.eql([1, 2]);
+
+      delete proj4.defs.enu;
+      delete proj4.defs.neu;
+      clearAllProjections();
+      addCommon();
+    });
   });
 
   describe('ol.proj.Projection.prototype.getMetersPerUnit()', function () {