Fix world envelope builder when crossing Greenwich meridian

src/main/java/org/opentripplanner/service/worldenvelope/model/WorldEnvelopeBuilder.java

@@ -86,7 +86,9 @@ public WorldEnvelope build() {
     // A small gap between the east and west longitude at 0 degrees implies that the Envelope
     // should include the 0 degrees longitude(meridian), and be split at 180 degrees.
     if (dist0 < dist180) {
-      return new WorldEnvelope(minLat, maxLonWest, maxLat, maxLonEast, transitMedianCenter);
+      // here we need to use the minLonWest as we want to go the furthest west we can and further
+      // west means smaller (negative) numbers of longitude
+      return new WorldEnvelope(minLat, minLonWest, maxLat, maxLonEast, transitMedianCenter);
     } else {
       return new WorldEnvelope(minLat, minLonEast, maxLat, minLonWest, transitMedianCenter);
     }

src/test/java/org/opentripplanner/service/worldenvelope/model/WorldEnvelopeTest.java

@@ -52,6 +52,27 @@ void testEast() {
     assertTrue(EAST.transitMedianCenter().isEmpty());
   }
 
+  @Test
+  void crossingGreenwich() {
+    // Colchester, east of London
+    WgsCoordinate COLCHESTER = new WgsCoordinate(51.8926, 0.8981);
+    // Swindon, west of London
+    WgsCoordinate SWINDON = new WgsCoordinate(51.5711, -1.7880);
+    // Cutty Sark, very slightly west of Greenwich
+    WgsCoordinate CUTTY_SARK = new WgsCoordinate(51.4819,-0.0106);
+    var env = WorldEnvelope
+      .of()
+      .expandToIncludeStreetEntities(COLCHESTER.latitude(), COLCHESTER.longitude())
+      .expandToIncludeStreetEntities(SWINDON.latitude(), SWINDON.longitude())
+      .expandToIncludeStreetEntities(CUTTY_SARK.latitude(), CUTTY_SARK.longitude())
+      .build();
+    assertEquals(CUTTY_SARK.latitude(), env.lowerLeft().latitude());
+    assertEquals(SWINDON.longitude(), env.lowerLeft().longitude());
+
+    assertEquals(COLCHESTER.longitude(), env.upperRight().longitude());
+    assertEquals(COLCHESTER.latitude(), env.upperRight().latitude());
+  }
+
   @Test
   void transitMedianCenter() {
     var expectedCenter = new WgsCoordinate(S10, E50);