Add OSM destination check (#1024)

Project.toml

@@ -1,7 +1,7 @@
 name = "Agents"
 uuid = "46ada45e-f475-11e8-01d0-f70cc89e6671"
 authors = ["George Datseris", "Tim DuBois", "Aayush Sabharwal", "Ali Vahdati", "Adriano Meligrana"]
-version = "6.0.8"
+version = "6.0.9"
 
 [deps]
 CSV = "336ed68f-0bac-5ca0-87d4-7b16caf5d00b"

src/spaces/openstreetmap.jl

@@ -230,8 +230,12 @@ keywords are passed to
 [`LightOSM.shortest_path`](https://deloittedigitalapac.github.io/LightOSM.jl/docs/shortest_path/#LightOSM.shortest_path).
 
 Return `true` if a path to `dest` exists, and hence the route planning was successful.
-Otherwise return `false`. Specifying `return_trip = true` also requires the existence
-of a return path for a route to be planned.
+Otherwise return `false`. When `dest` is an invalid position, i.e. if it contains node
+indices that are not in the graph, or if the distance along the road is not between zero and
+the length of the road, return `false` as well. 
+
+Specifying `return_trip = true` also requires the existence of a return path for a route to
+be planned.
 """
 function Agents.plan_route!(
         agent::AbstractAgent,
@@ -241,6 +245,7 @@ function Agents.plan_route!(
         kwargs...
     )
 
+    isa_valid_position(dest, model) || return false
     delete!(abmspace(model).routes, agent.id) # clear old route
     same_position(agent.pos, dest, model) && return true
 
@@ -368,6 +373,12 @@ function Agents.plan_route!(
     return true
 end
 
+function isa_valid_position(pos::Tuple{Int,Int,Float64}, model::ABM{<:OpenStreetMapSpace})
+    index_to_node = abmspace(model).map.index_to_node
+    return haskey(index_to_node, pos[1]) && haskey(index_to_node, pos[2]) &&
+        0.0 ≤ pos[3] ≤ road_length(pos, model)
+end
+
 # Allows passing destination as a node number
 Agents.plan_route!(agent::AbstractAgent, dest::Int, model; kwargs...) =
     plan_route!(agent, (dest, dest, 0.0), model; kwargs...)

test/osm_tests.jl

@@ -65,6 +65,18 @@ end
 
         @test OSM.road_length(model[1].pos, model) ≈ 0.0002591692620559716
         @test OSM.road_length(finish_road[1], finish_road[2], model) ≈ 0.00030269737299400725
+
+        # Test that if the destination is invalid, route planning fails (returns `false`)
+        @testset "test invalid destination: $dest" for dest in (
+            # Distance along road is greater than the length of the road:
+            (finish_road[1], finish_road[2], 1.2 * OSM.road_length(finish_road, model)),
+            # Distance along road is negative:
+            (finish_road[1], finish_road[2], -1.0),
+            # Road does not exist:
+            (finish_road[1], Graphs.nv(abmspace(model).map.graph) + 1, 0.5)
+        )
+            @test !plan_route!(model[1], dest, model)
+        end
     end
 
     @testset "Moving along routes" begin