CoordinateSystem, almost good on first try

src/coordinatesystem.i

@@ -12,3 +12,7 @@
 %nn_shared_ptr(osgeo::proj::cs::DateTimeTemporalCS)
 %nn_shared_ptr(osgeo::proj::cs::TemporalCountCS)
 %nn_shared_ptr(osgeo::proj::cs::TemporalMeasureCS)
+
+// Meridian is nullable when not an nn pointer
+%typemap(ts) osgeo::proj::cs::MeridianPtr           "Meridian | null";
+%typemap(ts) const osgeo::proj::cs::MeridianPtr &   "Meridian | null";

src/optional.i

@@ -55,6 +55,11 @@
   }
 }
 // Return value, const reference, conversion by wrapping a constant object
+// This typemap is not entirely safe because we wrap an existing object
+// Normally, this object would be part of its parent object, but this
+// object can be garbage-collected and if the user decides to keep its
+// copy, this will be a dangling pointer
+// The only safe way to do it is to always copy each object
 %typemap(out)       const osgeo::proj::util::optional & {
   if ($1->has_value()) {
     $typemap(out, const $T0type &, 1=&(*$1), result=$result, argnum=$argnum);

test/shared/cs.test.ts

@@ -0,0 +1,75 @@
+import { assert } from 'chai';
+
+import qPROJ from 'proj.js';
+import type * as PROJ from 'proj.js';
+
+describe('CoordinateSystem with automatic import', () => {
+  let PROJ: Awaited<typeof qPROJ>;
+
+  let dbContext: PROJ.DatabaseContext;
+  let authFactory: PROJ.AuthorityFactory;
+  let authFactoryEPSG: PROJ.AuthorityFactory;
+  let crs: PROJ.CRS;
+  let geoCRS: PROJ.GeographicCRS;
+
+  before('init', async () => {
+    PROJ = await qPROJ;
+    dbContext = PROJ.DatabaseContext.create();
+    authFactory = PROJ.AuthorityFactory.create(dbContext, 'string');
+    authFactoryEPSG = PROJ.AuthorityFactory.create(dbContext, 'EPSG');
+    crs = authFactoryEPSG.createCoordinateReferenceSystem('3857');
+    geoCRS = crs.extractGeographicCRS();
+  });
+
+  it('class constructor inheritance', () => {
+    assert.instanceOf(PROJ.EllipsoidalCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.SphericalCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.CartesianCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.VerticalCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.AffineCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.OrdinalCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.ParametricCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.TemporalCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.DateTimeTemporalCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.TemporalCS, PROJ.CoordinateSystem.constructor);
+    assert.instanceOf(PROJ.TemporalMeasureCS, PROJ.CoordinateSystem.constructor);
+  });
+
+  it('static properties', () => {
+    assert.instanceOf(PROJ.AxisDirection.NORTH, PROJ.AxisDirection);
+    assert.instanceOf(PROJ.RangeMeaning.EXACT, PROJ.RangeMeaning);
+  });
+
+  it('extract CoordinateSystem', () => {
+    const cs = geoCRS.coordinateSystem();
+    assert.instanceOf(cs, PROJ.BaseObject);
+    assert.instanceOf(cs, PROJ.CoordinateSystem);
+    assert.instanceOf(cs, PROJ.EllipsoidalCS);
+  });
+
+  it('CoordinateSystemAxis', () => {
+    const cs = geoCRS.coordinateSystem();
+    const axis = cs.axisList();
+    assert.isArray(axis);
+    assert.isAbove(axis.length, 0);
+    axis.forEach((ax) => {
+      assert.instanceOf(ax, PROJ.CoordinateSystemAxis);
+      if (ax.meridian() !== null)
+        assert.instanceOf(ax.meridian(), PROJ.Meridian);
+      assert.instanceOf(ax.name(), PROJ.Identifier);
+      assert.instanceOf(ax.unit(), PROJ.UnitOfMeasure);
+    });
+  });
+
+  it('create w/ PropertyMap', () => {
+    // TODO: PropertyMap can be an automatic JS object
+    const pmap = new PROJ.PropertyMap();
+    pmap.set(PROJ.Identifier.CODE_KEY, '1337');
+    pmap.set(PROJ.Identifier.AUTHORITY_KEY, 'DeadCow');
+    pmap.set(PROJ.Identifier.EPSG, false);
+    const axis = PROJ.CoordinateSystemAxis.create(pmap, 'axis', PROJ.AxisDirection.NORTH_EAST, PROJ.UnitOfMeasure.METRE, null);
+    assert.instanceOf(axis, PROJ.CoordinateSystemAxis);
+    assert.isNull(axis.meridian());
+    assert.isTrue(axis.unit().equal(PROJ.UnitOfMeasure.METRE));
+  });
+});