Support for a user projection

test/spec/ol/proj.test.js

@@ -1,4 +1,12 @@
 import {
+  useGeographic,
+  getUserProjection,
+  setUserProjection,
+  clearUserProjection,
+  toUserCoordinate,
+  fromUserCoordinate,
+  toUserExtent,
+  fromUserExtent,
   addCommon,
   clearAllProjections,
   equivalent,
@@ -22,9 +30,114 @@ describe('ol.proj', function() {
 
   afterEach(function() {
     clearAllProjections();
+    clearUserProjection();
     addCommon();
   });
 
+  describe('useGeographic()', function() {
+    it('sets the user projection to Geographic/WGS-84', function() {
+      useGeographic();
+      const projection = getUserProjection();
+      expect(projection).to.be(getProjection('EPSG:4326'));
+    });
+  });
+
+  describe('getUserProjection()', function() {
+    it('returns null by default', function() {
+      expect(getUserProjection()).to.be(null);
+    });
+
+    it('returns the user projection if set', function() {
+      const projection = getProjection('EPSG:4326');
+      setUserProjection(projection);
+      expect(getUserProjection()).to.be(projection);
+    });
+  });
+
+  describe('setUserProjection()', function() {
+    it('accepts a string identifier', function() {
+      const projection = getProjection('EPSG:4326');
+      setUserProjection('EPSG:4326');
+      expect(getUserProjection()).to.be(projection);
+    });
+  });
+
+  describe('clearUserProjection()', function() {
+    it('clears the user projection', function() {
+      useGeographic();
+      clearUserProjection();
+      expect(getUserProjection()).to.be(null);
+    });
+  });
+
+  describe('toUserCoordinate()', function() {
+    it('transforms a point to the user projection', function() {
+      useGeographic();
+      const coordinate = fromLonLat([-110, 45]);
+      const user = toUserCoordinate(coordinate, 'EPSG:3857');
+      const transformed = transform(coordinate, 'EPSG:3857', 'EPSG:4326');
+      expect(user).to.eql(transformed);
+      expect(user).not.to.eql(coordinate);
+    });
+
+    it('returns the original if no user projection is set', function() {
+      const coordinate = fromLonLat([-110, 45]);
+      const user = toUserCoordinate(coordinate, 'EPSG:3857');
+      expect(user).to.be(coordinate);
+    });
+  });
+
+  describe('fromUserCoordinate()', function() {
+    it('transforms a point from the user projection', function() {
+      useGeographic();
+      const user = [-110, 45];
+      const coordinate = fromUserCoordinate(user, 'EPSG:3857');
+      const transformed = transform(user, 'EPSG:4326', 'EPSG:3857');
+      expect(coordinate).to.eql(transformed);
+      expect(user).not.to.eql(coordinate);
+    });
+
+    it('returns the original if no user projection is set', function() {
+      const user = fromLonLat([-110, 45]);
+      const coordinate = fromUserCoordinate(user, 'EPSG:3857');
+      expect(coordinate).to.be(user);
+    });
+  });
+
+  describe('toUserExtent()', function() {
+    it('transforms an extent to the user projection', function() {
+      useGeographic();
+      const extent = transformExtent([-110, 45, -100, 50], 'EPSG:4326', 'EPSG:3857');
+      const user = toUserExtent(extent, 'EPSG:3857');
+      const transformed = transformExtent(extent, 'EPSG:3857', 'EPSG:4326');
+      expect(user).to.eql(transformed);
+      expect(user).not.to.eql(extent);
+    });
+
+    it('returns the original if no user projection is set', function() {
+      const extent = transformExtent([-110, 45, -100, 50], 'EPSG:4326', 'EPSG:3857');
+      const user = toUserExtent(extent, 'EPSG:3857');
+      expect(user).to.be(extent);
+    });
+  });
+
+  describe('fromUserExtent()', function() {
+    it('transforms an extent from the user projection', function() {
+      useGeographic();
+      const user = [-110, 45, -100, 50];
+      const extent = fromUserExtent(user, 'EPSG:3857');
+      const transformed = transformExtent(user, 'EPSG:4326', 'EPSG:3857');
+      expect(extent).to.eql(transformed);
+      expect(extent).not.to.eql(user);
+    });
+
+    it('returns the original if no user projection is set', function() {
+      const user = transformExtent([-110, 45, -100, 50], 'EPSG:4326', 'EPSG:3857');
+      const extent = fromUserExtent(user, 'EPSG:3857');
+      expect(extent).to.be(user);
+    });
+  });
+
   describe('toLonLat()', function() {
     const cases = [{
       from: [0, 0],