Added a test case for issue #25.

NRedisGraph.Tests/Issues/Number25.cs

@@ -0,0 +1,85 @@
+using System.Collections.Generic;
+using StackExchange.Redis;
+using Xunit;
+
+namespace NRedisGraph.Tests.Issues;
+
+public class Number25 : BaseTest
+{
+    private ConnectionMultiplexer _readWriteMultiplexer;
+    private ConnectionMultiplexer _readonlyMultiplexer;
+
+    private RedisGraph _readonlyApi;
+    private RedisGraph _readWriteApi;
+
+    protected override void BeforeTest()
+    {
+        // Setup the multiplexers.
+        _readonlyMultiplexer = ConnectionMultiplexer.Connect("tombaserver.local:10000,tombaserver.local:10001");
+        _readWriteMultiplexer = ConnectionMultiplexer.Connect("tombaserver.local:10000,tombaserver.local:10001");
+
+        // Setup RedisGraph API...
+        _readonlyApi = new RedisGraph(_readonlyMultiplexer.GetDatabase(0));
+        _readWriteApi = new RedisGraph(_readWriteMultiplexer.GetDatabase(0));
+
+        // Setup the data.
+        _readWriteApi.GraphQuery("issue25", "CREATE (:Person {username: 'John', age: 20})");
+        _readWriteApi.GraphQuery("issue25", "CREATE (:Person {username: 'Peter', age: 23})");
+        _readWriteApi.GraphQuery("issue25", "CREATE (:Person {username: 'Steven', age: 30})");        
+    }
+
+    protected override void AfterTest()
+    {
+        _readWriteApi.DeleteGraph("issue25");
+        _readWriteMultiplexer.Dispose();
+
+        _readonlyMultiplexer.Dispose();
+    }
+
+    [Fact(Skip="Need a read only node...")]
+    public void IssueReproduction()
+    {
+        // Read from the read-only replica
+        string readQuery = "MATCH x=(p:Person) RETURN nodes(x) as nodes";
+
+        ResultSet records = _readonlyApi.GraphReadOnlyQuery("issue25", readQuery);
+
+        var result = new List<Person>();
+
+        foreach (Record record in records) // Here it throws the exception (On the iteration)
+        {
+            var nodes = record.GetValue<object[]>("nodes");
+
+            foreach (var node in nodes)
+            {
+                if (node is Node castedNode)
+                {
+                    Person person = GetPersonInfo(castedNode);
+
+                    result.Add(new Person(person.Name, person.Age));
+                }
+            }
+        }
+    }
+
+    private static Person GetPersonInfo(Node node)
+    {
+        var name = node.PropertyMap["username"];
+        var age = node.PropertyMap["age"];
+
+        return new Person(name.Value.ToString(), (long)age.Value);
+    }
+}
+
+public class Person
+{
+    public string Name { get; }
+
+    public long Age { get; }
+
+    public Person(string name, long age)
+    {
+        Name = name;
+        Age = age;
+    }
+}