Merge pull request #205 from barbeau/simplifyInputChange

Fix #204 - Don't change reference for last point in PolyUtil.simplify()

Author: broady

library/src/com/google/maps/android/PolyUtil.java

@@ -313,12 +313,13 @@ public static List<LatLng> simplify(List<LatLng> poly, double tolerance) {
         }
 
         boolean closedPolygon = isClosedPolygon(poly);
+        LatLng lastPoint = null;
 
         // Check if the provided poly is a closed polygon
         if (closedPolygon) {
             // Add a small offset to the last point for Douglas-Peucker on polygons (see #201)
             final double OFFSET = 0.00000000001;
-            LatLng lastPoint = poly.get(poly.size() - 1);
+            lastPoint = poly.get(poly.size() - 1);
             // LatLng.latitude and .longitude are immutable, so replace the last point
             poly.remove(poly.size() - 1);
             poly.add(new LatLng(lastPoint.latitude + OFFSET, lastPoint.longitude + OFFSET));
@@ -359,9 +360,9 @@ public static List<LatLng> simplify(List<LatLng> poly, double tolerance) {
         }
 
         if (closedPolygon) {
-            // Replace last point of input (w/ offset) with a copy of first to re-close the polygon
+            // Replace last point w/ offset with the original last point to re-close the polygon
             poly.remove(poly.size() - 1);
-            poly.add(new LatLng(poly.get(0).latitude, poly.get(0).longitude));
+            poly.add(lastPoint);
         }
 
         // Generate the simplified line

library/tests/src/com/google/maps/android/PolyUtilTest.java

@@ -368,7 +368,13 @@ private List<LatLng> copyList(List<LatLng> original) {
      * @param beforeInput a copy of the list before it is passed into PolyUtil.simplify()
      */
     private void assertInputUnchanged(List<LatLng> afterInput, List<LatLng> beforeInput) {
+        // Check values
         assertEquals(beforeInput, afterInput);
+
+        // Check references
+        for (int i = 0; i < beforeInput.size(); i++) {
+            assertTrue(afterInput.get(i) == beforeInput.get(i));
+        }
     }
 
     public void testIsClosedPolygon() {