fix(geocoder): update implementation and adjust replace script

scripts/replace.js

@@ -35,7 +35,7 @@ function applyReplacements(content, env) {
     // Leaflet uses LatLng
     else options = options.replace('38.8995,-77.0269', latlng)
   }
-  if (NOMINATIM_ENDPOINT) options = options.replace('https://nominatim.openstreetmap.org/', NOMINATIM_ENDPOINT)
+  if (NOMINATIM_ENDPOINT) options = options.replace(/https?:\/\/nominatim\.openstreetmap\.org\/?/g, function() { return NOMINATIM_ENDPOINT; })
 
   return options
 }

src/geocoder.js

@@ -52,7 +52,13 @@ function parseCoords(query) {
 // Also bridges leaflet-control-geocoder's Promise API to the callback-based API
 // that leaflet-routing-machine's autocomplete expects.
 geocoder.coordPreserving = function(nominatimUrl) {
-  var nominatim = L.Control.Geocoder.nominatim({serviceUrl: nominatimUrl});
+  var nominatim;
+  if (typeof nominatimUrl === 'string' && nominatimUrl.trim().length > 0) {
+    nominatim = L.Control.Geocoder.nominatim({serviceUrl: nominatimUrl});
+  } else {
+    // Preserve Leaflet-Control-Geocoder's default behavior when no URL provided
+    nominatim = L.Control.Geocoder.nominatim();
+  }
 
   function withCallback(promise, cb, context) {
     return promise.then(function(results) {

test/geocoder.test.js

@@ -29,4 +29,25 @@ describe('geocoder.coordPreserving', () => {
     expect(results[0].center.lng).toBeCloseTo(-118.141254);
     expect(reverseMock).toHaveBeenCalled();
   });
+
+  test('invokes L.Control.Geocoder.nominatim() with no args when nominatimUrl omitted', () => {
+    const reverseMock = jest.fn(() => Promise.resolve([]));
+    const geocodeMock = jest.fn(() => Promise.resolve([]));
+    const nominatimFactory = jest.fn(() => ({ reverse: reverseMock, geocode: geocodeMock }));
+
+    jest.doMock('leaflet', () => ({
+      Control: { Geocoder: { nominatim: nominatimFactory } },
+      CRS: { EPSG3857: { scale: () => 1 } },
+      latLng: (lat, lng) => ({ lat: +lat, lng: +lng, toBounds: () => ({}) }),
+      extend: Object.assign
+    }));
+
+    const geocoder = require('../src/geocoder');
+    const L = require('leaflet');
+
+    // Call without argument to ensure default nominatim factory is used
+    geocoder.coordPreserving();
+    expect(L.Control.Geocoder.nominatim).toHaveBeenCalled();
+    expect(L.Control.Geocoder.nominatim.mock.calls[0].length).toBe(0);
+  });
 });