xmpp: Add test for negotiation behaviour

lib/xmpp/connection.dart

@@ -23,6 +23,7 @@ import "package:moxxyv2/xmpp/xeps/xep_0030/cachemanager.dart";
 import "package:moxxyv2/xmpp/xeps/xep_0352.dart";
 import "package:moxxyv2/xmpp/xeps/xep_0198/xep_0198.dart";
 
+import "package:meta/meta.dart";
 import "package:uuid/uuid.dart";
 import "package:synchronized/synchronized.dart";
 import "package:logging/logging.dart";
@@ -166,6 +167,11 @@ class XmppConnection {
 
   List<String> get serverFeatures => _serverFeatures;
 
+  /// Return the registered feature negotiator that has id [id]. Returns null if
+  /// none can be found.
+  @visibleForTesting
+  XmppFeatureNegotiatorBase? getNegotiatorById(String id) => _featureNegotiators[id];
+  
   /// Registers an [XmppManagerBase] sub-class as a manager on this connection.
   /// [sortHandlers] should NOT be touched. It specified if the handler priorities
   /// should be set up. The only time this should be false is when called via
@@ -183,7 +189,7 @@ class XmppConnection {
         getFullJID: () => _connectionSettings.jid.withResource(_resource),
         getSocket: () => _socket,
         getConnection: () => this,
-        getNegotiatorById: (id) => _featureNegotiators[id],
+        getNegotiatorById: getNegotiatorById,
     ));
 
     final id = manager.getId();
@@ -571,12 +577,13 @@ class XmppConnection {
   /// Returns true if we can still negotiate. Returns false if no negotiator is
   /// matching and ready.
   bool _isNegotiationPossible(List<XMLNode> features) {
-    return _getNextNegotiator(features, log: false) != null;
+    return getNextNegotiator(features, log: false) != null;
   }
 
   /// Returns the next negotiator that matches [features]. Returns null if none can be
   /// picked. If [log] is true, then the list of matching negotiators will be logged.
-  XmppFeatureNegotiatorBase? _getNextNegotiator(List<XMLNode> features, {bool log = true}) {
+  @visibleForTesting
+  XmppFeatureNegotiatorBase? getNextNegotiator(List<XMLNode> features, {bool log = true}) {
     final matchingNegotiators = _featureNegotiators.values
       .where(
         (XmppFeatureNegotiatorBase negotiator) {
@@ -627,7 +634,7 @@ class XmppConnection {
 
           await _onNegotiationsDone();
         } else {
-          _currentNegotiator = _getNextNegotiator(_streamFeatures);
+          _currentNegotiator = getNextNegotiator(_streamFeatures);
           _log.finest("Chose ${_currentNegotiator!.id} as next negotiator");
 
           final fakeStanza = XMLNode(
@@ -650,7 +657,7 @@ class XmppConnection {
         await _onNegotiationsDone();
       } else {
         _log.finest('Picking new negotiator...');
-        _currentNegotiator = _getNextNegotiator(_streamFeatures);
+        _currentNegotiator = getNextNegotiator(_streamFeatures);
         _log.finest("Chose $_currentNegotiator as next negotiator");
         final fakeStanza = XMLNode(
           tag: "stream:features",
@@ -663,7 +670,7 @@ class XmppConnection {
   }
   
   /// Called whenever we receive data that has been parsed as XML.
-  void handleXmlStream(XMLNode node) async {
+  Future<void> handleXmlStream(XMLNode node) async {
     switch (_routingState) {
       case RoutingState.negotiating:
         if (_currentNegotiator != null) {
@@ -682,7 +689,7 @@ class XmppConnection {
             // Mandatory features are done but can we still negotiate more?
             if (_isNegotiationPossible(node.children)) {// We can still negotiate features, so do that.
               _log.finest('All required stream features done! Continuing negotiation');
-              _currentNegotiator = _getNextNegotiator(node.children);
+              _currentNegotiator = getNextNegotiator(node.children);
               _log.finest("Chose $_currentNegotiator as next negotiator");
               await _currentNegotiator!.negotiate(node);
               await _checkCurrentNegotiator();
@@ -697,7 +704,7 @@ class XmppConnection {
               return;
             }
 
-            _currentNegotiator = _getNextNegotiator(node.children);
+            _currentNegotiator = getNextNegotiator(node.children);
             _log.finest("Chose $_currentNegotiator as next negotiator");
             await _currentNegotiator!.negotiate(node);
             await _checkCurrentNegotiator();

test/negotiator_test.dart

@@ -0,0 +1,68 @@
+import "package:test/test.dart";
+import "package:moxxyv2/xmpp/stringxml.dart";
+import "package:moxxyv2/xmpp/connection.dart";
+import "package:moxxyv2/xmpp/reconnect.dart";
+import "package:moxxyv2/xmpp/presence.dart";
+import "package:moxxyv2/xmpp/negotiators/negotiator.dart";
+
+import "helpers/logging.dart";
+
+const exampleXmlns1 = "im:moxxy:example1";
+const exampleNamespace1 = "im.moxxy.test.example1";
+const exampleXmlns2 = "im:moxxy:example2";
+const exampleNamespace2 = "im.moxxy.test.example2";
+
+class StubNegotiator1 extends XmppFeatureNegotiatorBase {
+  StubNegotiator1() : called = false, super(1, false, exampleXmlns1, exampleNamespace1);
+
+  bool called;
+  
+  @override
+  Future<void> negotiate(XMLNode nonza) async {
+    state = NegotiatorState.done;
+  }
+}
+
+class StubNegotiator2 extends XmppFeatureNegotiatorBase {
+  StubNegotiator2() : called = false, super(10, false, exampleXmlns2, exampleNamespace2);
+
+  bool called;
+  
+  @override
+  Future<void> negotiate(XMLNode nonza) async {
+    called = true;
+    state = NegotiatorState.done;
+  }
+}
+
+void main() {
+  initLogger();
+
+  final connection = XmppConnection(TestingReconnectionPolicy())
+    ..registerFeatureNegotiators([
+      StubNegotiator1(),
+      StubNegotiator2(),
+    ])
+    ..registerManagers([
+      PresenceManager(),
+    ]);
+  final features = [
+    XMLNode.xmlns(tag: "example1", xmlns: exampleXmlns1),
+    XMLNode.xmlns(tag: "example2", xmlns: exampleXmlns2),
+  ];
+
+  test("Test the priority system", () {
+    expect(connection.getNextNegotiator(features)?.id, exampleNamespace2);
+  });
+
+  test("Test negotiating features with no stream restarts", () async {
+    // TODO: Use a simple connection setup to test this
+    final streamFeatures = XMLNode(tag: "stream:features", children: features);
+    await connection.handleXmlStream(streamFeatures);
+
+    final negotiator1 = connection.getNegotiatorById(exampleNamespace1) as StubNegotiator1?;
+    final negotiator2 = connection.getNegotiatorById(exampleNamespace2) as StubNegotiator2?;
+    expect(negotiator1?.called, true);
+    expect(negotiator2?.called, true);
+  });
+}