feat(dcl): BrowseNext continuation paging + StubOpcUaClient canned browse (T15)

tests/ZB.MOM.WW.ScadaBridge.DataConnectionLayer.Tests/Actors/DataConnectionManagerBrowseHandlerTests.cs

@@ -105,7 +105,7 @@ public class DataConnectionManagerBrowseHandlerTests : TestKit
             new BrowseNode("ns=2;s=B", "B", BrowseNodeClass.Object,   HasChildren: true),
         };
         ((IBrowsableDataConnection)adapter)
-            .BrowseChildrenAsync(null, Arg.Any<CancellationToken>())
+            .BrowseChildrenAsync(null, Arg.Any<string?>(), Arg.Any<CancellationToken>())
             .Returns(new BrowseChildrenResult(children, Truncated: false));
 
         _factory.Create("OpcUa", Arg.Any<IDictionary<string, string>>())
@@ -139,7 +139,7 @@ public class DataConnectionManagerBrowseHandlerTests : TestKit
         ((IDataConnection)adapter).Status.Returns(ConnectionHealth.Connected);
 
         ((IBrowsableDataConnection)adapter)
-            .BrowseChildrenAsync(Arg.Any<string?>(), Arg.Any<CancellationToken>())
+            .BrowseChildrenAsync(Arg.Any<string?>(), Arg.Any<string?>(), Arg.Any<CancellationToken>())
             .Returns(Task.FromException<BrowseChildrenResult>(
                 new ConnectionNotConnectedException("OPC UA session is not connected.")));
 
@@ -183,7 +183,7 @@ public class DataConnectionManagerBrowseHandlerTests : TestKit
         ((IDataConnection)adapter).Status.Returns(ConnectionHealth.Connected);
 
         ((IBrowsableDataConnection)adapter)
-            .BrowseChildrenAsync(Arg.Any<string?>(), Arg.Any<CancellationToken>())
+            .BrowseChildrenAsync(Arg.Any<string?>(), Arg.Any<string?>(), Arg.Any<CancellationToken>())
             .Returns(Task.FromException<BrowseChildrenResult>(new NotSupportedException(reason)));
 
         _factory.Create("MxGateway", Arg.Any<IDictionary<string, string>>())
@@ -226,7 +226,7 @@ public class DataConnectionManagerBrowseHandlerTests : TestKit
             .Returns(Task.CompletedTask);
         ((IDataConnection)adapter).Status.Returns(ConnectionHealth.Connected);
         ((IBrowsableDataConnection)adapter)
-            .BrowseChildrenAsync(null, Arg.Any<CancellationToken>())
+            .BrowseChildrenAsync(null, Arg.Any<string?>(), Arg.Any<CancellationToken>())
             .Returns(new BrowseChildrenResult(bigList, Truncated: false));
 
         _factory.Create("OpcUa", Arg.Any<IDictionary<string, string>>())

tests/ZB.MOM.WW.ScadaBridge.DataConnectionLayer.Tests/Adapters/OpcUaDataConnectionBrowseTests.cs

@@ -25,7 +25,7 @@ public class OpcUaDataConnectionBrowseTests
         var expected = new BrowseChildrenResult(
             new[] { new BrowseNode("ns=2;s=X", "X", BrowseNodeClass.Variable, false) },
             Truncated: false);
-        client.BrowseChildrenAsync("ns=2;s=Parent", Arg.Any<CancellationToken>())
+        client.BrowseChildrenAsync("ns=2;s=Parent", Arg.Any<string?>(), Arg.Any<CancellationToken>())
             .Returns(expected);
 
         var adapter = new OpcUaDataConnection(factory, NullLogger<OpcUaDataConnection>.Instance);
@@ -36,6 +36,6 @@ public class OpcUaDataConnectionBrowseTests
         var actual = await adapter.BrowseChildrenAsync("ns=2;s=Parent");
 
         Assert.Same(expected, actual);
-        await client.Received(1).BrowseChildrenAsync("ns=2;s=Parent", Arg.Any<CancellationToken>());
+        await client.Received(1).BrowseChildrenAsync("ns=2;s=Parent", Arg.Any<string?>(), Arg.Any<CancellationToken>());
     }
 }

tests/ZB.MOM.WW.ScadaBridge.DataConnectionLayer.Tests/StubOpcUaClientBrowseTests.cs

@@ -0,0 +1,92 @@
+using ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Protocol;
+using ZB.MOM.WW.ScadaBridge.DataConnectionLayer.Adapters;
+
+namespace ZB.MOM.WW.ScadaBridge.DataConnectionLayer.Tests;
+
+/// <summary>
+/// M7-B2 (T15): <see cref="StubOpcUaClient"/> serves a small canned address-space
+/// tree so DCL browse/paging flows can be exercised without a live OPC UA server.
+/// The stub also fakes BrowseNext continuation paging on <c>Folder1</c> so the
+/// continuation-token round-trip is testable end-to-end against the contract.
+/// </summary>
+public class StubOpcUaClientBrowseTests
+{
+    // StubOpcUaClient is internal; reached here via InternalsVisibleTo on the
+    // DataConnectionLayer assembly (the test project is already a friend, since
+    // other tests in this project new up internal adapter types).
+    private static async Task<IOpcUaClient> ConnectedStubAsync()
+    {
+        var client = new StubOpcUaClient();
+        await client.ConnectAsync("opc.tcp://stub", null, CancellationToken.None);
+        return client;
+    }
+
+    [Fact]
+    public async Task BrowseRoot_ReturnsTwoFolders_NoContinuation()
+    {
+        await using var client = (StubOpcUaClient)await ConnectedStubAsync();
+
+        var result = await client.BrowseChildrenAsync(parentNodeId: null);
+
+        Assert.False(result.Truncated);
+        Assert.Null(result.ContinuationToken);
+        Assert.Collection(
+            result.Children,
+            n =>
+            {
+                Assert.Equal("Folder1", n.DisplayName);
+                Assert.Equal(BrowseNodeClass.Object, n.NodeClass);
+                Assert.True(n.HasChildren);
+            },
+            n =>
+            {
+                Assert.Equal("Folder2", n.DisplayName);
+                Assert.Equal(BrowseNodeClass.Object, n.NodeClass);
+                Assert.False(n.HasChildren);
+            });
+    }
+
+    [Fact]
+    public async Task BrowseFolder1_NoToken_ReturnsTag1_AndContinuationToken()
+    {
+        await using var client = (StubOpcUaClient)await ConnectedStubAsync();
+
+        var result = await client.BrowseChildrenAsync(parentNodeId: "Folder1");
+
+        Assert.True(result.Truncated);
+        Assert.Equal("STUB_PAGE2", result.ContinuationToken);
+        var only = Assert.Single(result.Children);
+        Assert.Equal("Tag1", only.DisplayName);
+        Assert.Equal(BrowseNodeClass.Variable, only.NodeClass);
+        Assert.False(only.HasChildren);
+    }
+
+    [Fact]
+    public async Task BrowseFolder1_WithContinuationToken_ReturnsTag2_AndNoFurtherContinuation()
+    {
+        await using var client = (StubOpcUaClient)await ConnectedStubAsync();
+
+        var result = await client.BrowseChildrenAsync(
+            parentNodeId: "Folder1",
+            continuationToken: "STUB_PAGE2");
+
+        Assert.False(result.Truncated);
+        Assert.Null(result.ContinuationToken);
+        var only = Assert.Single(result.Children);
+        Assert.Equal("Tag2", only.DisplayName);
+        Assert.Equal(BrowseNodeClass.Variable, only.NodeClass);
+        Assert.False(only.HasChildren);
+    }
+
+    [Fact]
+    public async Task BrowseLeaf_ReturnsEmpty_NoContinuation()
+    {
+        await using var client = (StubOpcUaClient)await ConnectedStubAsync();
+
+        var result = await client.BrowseChildrenAsync(parentNodeId: "Folder2");
+
+        Assert.False(result.Truncated);
+        Assert.Null(result.ContinuationToken);
+        Assert.Empty(result.Children);
+    }
+}