make NetworkGraphArgument nonnullable

Author: arik-so

ci/LDKSwift/Sources/LDKSwift/batteries/ChannelManagerConstructor.swift

@@ -118,7 +118,7 @@ public class ChannelManagerConstructor: NativeTypeWrapper {
     public private(set) var channel_monitors: [(ChannelMonitor, [UInt8])]
 
 
-    public init(channelManagerSerialized: [UInt8], channelMonitorsSerialized: [[UInt8]], networkGraph: NetworkGraphArgument?, filter: Filter?, params: ChannelManagerConstructionParameters) throws {
+    public init(channelManagerSerialized: [UInt8], channelMonitorsSerialized: [[UInt8]], networkGraph: NetworkGraphArgument, filter: Filter?, params: ChannelManagerConstructionParameters) throws {
 
         self.constructionParameters = params
 
@@ -150,18 +150,15 @@ public class ChannelManagerConstructor: NativeTypeWrapper {
 
         print("Collected channel monitors, reading channel manager")
 
-        if let netGraph = networkGraph {
-            switch netGraph {
-            case .instance(let graph):
-                self.netGraph = graph
-            case .serialized(let serializedNetworkGraph):
-                let netGraphResult = NetworkGraph.read(ser: serializedNetworkGraph, arg: params.logger)
-                if !netGraphResult.isOk(){
-                    throw InvalidSerializedDataError.invalidSerializedNetworkGraph
-                }
-                self.netGraph = netGraphResult.getValue()
+        switch networkGraph {
+        case .instance(let graph):
+            self.netGraph = graph
+        case .serialized(let serializedNetworkGraph):
+            let netGraphResult = NetworkGraph.read(ser: serializedNetworkGraph, arg: params.logger)
+            if !netGraphResult.isOk(){
+                throw InvalidSerializedDataError.invalidSerializedNetworkGraph
             }
-            
+            self.netGraph = netGraphResult.getValue()
         }
 
         // TODO: figure out better way to obtain a router

ci/LDKSwift/Tests/LDKSwiftTests/LDKSwiftTests.swift

@@ -70,7 +70,9 @@ class LDKSwiftTests: XCTestCase {
             txBroadcaster: broadcaster,
             logger: logger
         )
-        let channelManagerConstructor = try ChannelManagerConstructor(channelManagerSerialized: serialized_channel_manager, channelMonitorsSerialized: serializedChannelMonitors, networkGraph: nil, filter: filter, params: constructionParameters)
+        
+        let networkGraph = NetworkGraph(network: .Regtest, logger: logger)
+        let channelManagerConstructor = try ChannelManagerConstructor(channelManagerSerialized: serialized_channel_manager, channelMonitorsSerialized: serializedChannelMonitors, networkGraph: NetworkGraphArgument.instance(networkGraph), filter: filter, params: constructionParameters)
 
         let channelManager = channelManagerConstructor.channelManager;
         let cmPersister = TestChannelManagerPersister(channelManager: channelManager)

ci/LDKSwift/Tests/LDKSwiftTests/TestChannelManagerPersister.swift

@@ -30,6 +30,10 @@ class TestChannelManagerPersister : Persister, ExtendedChannelManagerPersister {
     override func persistScorer(scorer: Bindings.WriteableScore) -> Bindings.Result_NoneErrorZ {
         .initWithOk()
     }
+    
+    override func persistGraph(networkGraph: Bindings.NetworkGraph) -> Bindings.Result_NoneErrorZ {
+        .initWithOk()
+    }
 }
 
 class FloatingChannelManagerPersister : Persister{