Fixes weight being Double.MAX_VALUE when from=to for edge-based algos.

Signed-off-by: easbar <[email protected]>

Author: easbar

core/src/main/java/com/graphhopper/routing/AbstractBidirAlgo.java

@@ -128,8 +128,12 @@ protected void postInit(int from, int to) {
             }
         } else if (from == to) {
             // special case of identical start and end
+            if (currFrom.weight != 0 || currTo.weight != 0) {
+                throw new IllegalStateException("If from=to, the starting weight must be zero for from and to");
+            }
             bestPath.sptEntry = currFrom;
             bestPath.edgeTo = currTo;
+            bestPath.setWeight(0);
             finishedFrom = true;
             finishedTo = true;
         }

core/src/main/java/com/graphhopper/routing/Path.java

@@ -379,10 +379,10 @@ public InstructionList calcInstructions(BooleanEncodedValue roundaboutEnc, final
      */
     public Map<String, List<PathDetail>> calcDetails(List<String> requestedPathDetails, PathDetailsBuilderFactory pathBuilderFactory, int previousIndex) {
         if (!isFound() || requestedPathDetails.isEmpty())
-            return Collections.EMPTY_MAP;
+            return Collections.emptyMap();
         List<PathDetailsBuilder> pathBuilders = pathBuilderFactory.createPathDetailsBuilders(requestedPathDetails, encoder, weighting);
         if (pathBuilders.isEmpty())
-            return Collections.EMPTY_MAP;
+            return Collections.emptyMap();
 
         forEveryEdge(new PathDetailsFromEdges(pathBuilders, previousIndex));
 
@@ -399,7 +399,7 @@ public Map<String, List<PathDetail>> calcDetails(List<String> requestedPathDetai
 
     @Override
     public String toString() {
-        return "distance:" + getDistance() + ", edges:" + edgeIds.size();
+        return "found: " + found + ", weight: " + weight + ", time: " + time + ", distance: " + distance + ", edges: " + edgeIds.size();
     }
 
     public String toDetailsString() {

core/src/test/java/com/graphhopper/routing/AbstractRoutingAlgorithmTester.java

@@ -201,8 +201,7 @@ public void testCalcShortestPath_sourceEqualsTarget() {
 
         RoutingAlgorithm algo = createAlgo(graph);
         Path p = algo.calcPath(0, 0);
-        assertEquals(p.toString(), IntArrayList.from(new int[]{0}), p.calcNodes());
-        assertEquals(p.toString(), 0, p.getDistance(), 1.e-6);
+        assertPathFromEqualsTo(p, 0);
     }
 
     @Test
@@ -633,26 +632,19 @@ public void testWithCoordinates() {
     @Test
     public void testCalcIfEmptyWay() {
         Path p = createAlgo(createTestStorage()).calcPath(0, 0);
-        assertEquals(p.calcNodes().toString(), 1, p.calcNodes().size());
-        assertEquals(p.toString(), 0, p.getDistance(), 1e-4);
+        assertPathFromEqualsTo(p, 0);
     }
 
     @Test
     public void testViaEdges_FromEqualsTo() {
         GraphHopperStorage ghStorage = createTestStorage();
         // identical tower nodes
         Path p = calcPathViaQuery(ghStorage, 0.001, 0.000, 0.001, 0.000);
-        assertTrue(p.isFound());
-        assertEquals(IntArrayList.from(0), p.calcNodes());
-        // assertEquals(1, p.calcPoints().size());
-        assertEquals(p.toString(), 0, p.getDistance(), 1e-4);
+        assertPathFromEqualsTo(p, 0);
 
         // identical query points on edge
         p = calcPath(ghStorage, 0, 1, 0, 1);
-        assertTrue(p.isFound());
-        assertEquals(IntArrayList.from(8), p.calcNodes());
-        // assertEquals(1, p.calcPoints().size());
-        assertEquals(p.toString(), 0, p.getDistance(), 1e-4);
+        assertPathFromEqualsTo(p, 8);
 
         // very close
         p = calcPathViaQuery(ghStorage, 0.00092, 0, 0.00091, 0);
@@ -967,4 +959,14 @@ Graph initEleGraph(Graph g) {
     protected GraphHopperStorage createMatrixGraph() {
         return createMatrixAlikeGraph(createGHStorage(false));
     }
+
+    private void assertPathFromEqualsTo(Path p, int node) {
+        assertTrue(p.isFound());
+        assertEquals(p.toString(), IntArrayList.from(node), p.calcNodes());
+        assertEquals(p.toString(), 1, p.calcPoints().size());
+        assertEquals(p.toString(), 0, p.calcEdges().size());
+        assertEquals(p.toString(), 0, p.getWeight(), 1e-4);
+        assertEquals(p.toString(), 0, p.getDistance(), 1e-4);
+        assertEquals(p.toString(), 0, p.getTime(), 1e-4);
+    }
 }