Fix bugs in lookup and add test case (#820)

fluffy/network/state/portal_protocol.nim

@@ -252,6 +252,7 @@ proc lookupDistances(target, dest: NodeId): seq[uint16] =
     if td - i > 0'u16:
       distances.add(td - i)
     inc i
+  distances
 
 proc lookupWorker(p: PortalProtocol, destNode: Node, target: NodeId):
     Future[seq[Node]] {.async.} =
@@ -261,7 +262,7 @@ proc lookupWorker(p: PortalProtocol, destNode: Node, target: NodeId):
   let nodesMessage = await p.findNode(destNode,  List[uint16, 256](distances))
   if nodesMessage.isOk():
     let records = recordsFromBytes(nodesMessage.get().enrs)
-    let verifiedNodes = verifyNodesRecords(records, destNode, @[0'u16])
+    let verifiedNodes = verifyNodesRecords(records, destNode, distances)
     nodes.add(verifiedNodes)
 
     # Attempt to add all nodes discovered

fluffy/tests/test_portal.nim

@@ -130,6 +130,36 @@ procSuite "Portal Tests":
     
     await test.stopTest()
 
+  asyncTest "Portal lookup nodes":
+      let
+        node1 = initDiscoveryNode(
+          rng, PrivateKey.random(rng[]), localAddress(20302))
+        node2 = initDiscoveryNode(
+          rng, PrivateKey.random(rng[]), localAddress(20303))
+        node3 = initDiscoveryNode(
+          rng, PrivateKey.random(rng[]), localAddress(20304))
+
+        proto1 = PortalProtocol.new(node1, testHandler)
+        proto2 = PortalProtocol.new(node2, testHandler)
+        proto3 = PortalProtocol.new(node3, testHandler)
+
+      # Node1 knows about Node2, and Node2 knows about Node3 which hold all content
+      check proto1.addNode(node2.localNode) == Added
+      check proto2.addNode(node3.localNode) == Added
+
+      check (await proto2.ping(node3.localNode)).isOk()
+
+      let lookuResult = await proto1.lookup(node3.localNode.id)
+
+      check:
+        # returned result should contain node3 as it is in node2 routing table
+        lookuResult.contains(node3.localNode)
+
+      await node1.closeWait()
+      await node2.closeWait()
+      await node3.closeWait()
+
+
   asyncTest "Portal FindContent/FoundContent - send enrs":
     let test = defaultTestCase(rng)