Fix incorrect weight fallback for distance-based weights

Author: oxidase

features/car/weight.feature

@@ -62,3 +62,28 @@ Feature: Car - weights
             | from | to | route       | speed   | weight |
             | a    | d  | ab,bc,cd,cd | 65 km/h | 44.4   |
             | a    | e  | ab,be,be    | 14 km/h | 112    |
+
+    Scenario: Distance weights
+        Given the profile file "car" extended with
+        """
+        api_version = 1
+        properties.weight_name = 'distance'
+        """
+
+        Given the node map
+            """
+            a---b---c
+                |
+                d
+            """
+
+        And the ways
+            | nodes |
+            | abc   |
+            | bd    |
+
+        When I route I should get
+            | waypoints | bearings | route     | distance | weights   | times          |
+            | a,b       | 90 90    | abc,abc   | 200m     | 200,0     | 11.1s,0s       |
+            | b,c       | 90 90    | abc,abc   | 200m     | 200,0     | 11.1s,0s       |
+            | a,d       | 90 180   | abc,bd,bd | 399.9m   | 200,200,0 | 13.2s,11.1s,0s |

profiles/lib/handlers.lua

@@ -441,7 +441,7 @@ end
 
 function Handlers.handle_weights(way,result,data,profile)
   if properties.weight_name == 'distance' then
-    result.weight = 0
+    result.weight = -1
      -- set weight rates to 1 for the distance weight, edge weights are distance / rate
     if (result.forward_mode ~= mode.inaccessible and result.forward_speed > 0) then
        result.forward_rate = 1