Add discovery v5.1 implementation

eth.nimble

@@ -53,12 +53,20 @@ proc runP2pTests() =
       "test_lru",
       "test_discoveryv5",
       "test_discv5_encoding",
+      "test_discv51_encoding",
       "test_routing_table"
     ]:
     runTest("tests/p2p/" & filename)
 
+proc runDiscv51Test() =
+  let path = "tests/p2p/test_discoveryv5"
+  echo "\nRunning: ", path
+  exec "nim c -r -d:UseDiscv51=true -d:release -d:chronicles_log_level=ERROR --verbosity:0 --hints:off " & path
+  rmFile path
+
 task test_p2p, "run p2p tests":
   runP2pTests()
+  runDiscv51Test()
 
 proc runRlpTests() =
   runTest("tests/rlp/all_tests")

eth/p2p/discoveryv5/dcli.nim

@@ -2,7 +2,16 @@ import
   std/[options, strutils],
   chronos, chronicles, chronicles/topics_registry, confutils, metrics,
   stew/byteutils, confutils/std/net,
-  eth/keys, eth/net/nat, protocol, enr, node
+  eth/keys, eth/net/nat, enr, node
+
+### This is all just temporary to be compatible with both versions
+const UseDiscv51* {.booldefine.} = false
+
+when UseDiscv51:
+  import protocolv1
+else:
+  import protocol
+###
 
 type
   DiscoveryCmd* = enum
@@ -166,7 +175,10 @@ proc run(config: DiscoveryConf) =
     else:
       echo "No Pong message returned"
   of findnode:
-    let nodes = waitFor d.findNode(config.findNodeTarget, config.distance)
+    when UseDiscv51:
+      let nodes = waitFor d.findNode(config.findNodeTarget, @[config.distance])
+    else:
+      let nodes = waitFor d.findNode(config.findNodeTarget, config.distance)
     if nodes.isOk():
       echo "Received valid records:"
       for node in nodes[]: