Hasher would not recognize internal references if it encounters the reference before the target node

CHANGELOG.md

@@ -52,6 +52,7 @@ and this project adheres _loosely_ to [Semantic Versioning](https://semver.org/s
 * During deserialization, `ModelMigrator` would add a feature to the wrong language if the node's concept is from a 
   different language as the feature.
 * `Comparer` didn't recognize internal references to nodes that are children in single containments.
+* `Hasher` would not recognize internal references if it encounters the reference before the target node. 
 ### Changed
 ### Removed
 ### Deprecated

src/LionWeb.Core/Core/Utilities/Hasher.cs

@@ -184,7 +184,7 @@ private void RegisterNode(IReadableNode node)
     {
         if (_referenceIndices.TryGetValue(node.GetId(), out var index))
         {
-            index.Internal = true;
+            _referenceIndices[node.GetId()] = index with { Internal = true };
             return;
         }
 
@@ -197,7 +197,7 @@ private int LookupReferenceIndex(IReadableNode node)
         {
             if (index.Index == _indexUnset)
             {
-                index.Index = ++_nextReferenceIndex;
+                _referenceIndices[node.GetId()] = index with { Index = ++_nextReferenceIndex };
             }
 
             return index.Index;
@@ -240,9 +240,9 @@ public interface IHash : IEquatable<IHash>;
     /// <param name="Hash">Hash code.</param>
     public ByteArrayHash(string Algorithm, byte[] Hash)
     {
-        if(Hash.Length < 4)
+        if (Hash.Length < 4)
             throw new ArgumentException("Hash must contain at least 4 bytes.");
-        
+
         this.Algorithm = Algorithm;
         this.Hash = Hash;
     }

test/LionWeb.Core.Test/Utilities/Hasher/HasherTests.cs

@@ -293,6 +293,17 @@ public void Reference_Internal_Equal_After()
         Assert.AreEqual(hashA, hashB);
     }
 
+    [TestMethod]
+    public void Reference_Internal_Equal_After_OtherId()
+    {
+        var targetA = new Line("Ta");
+        var hashA = new Hasher([new OffsetDuplicate("A") { Source = targetA }, targetA]).Hash();
+        var targetB = new Line("Tb");
+        var hashB = new Hasher([new OffsetDuplicate("B") { Source = targetB }, targetB]).Hash();
+
+        Assert.AreEqual(hashA, hashB);
+    }
+
     [TestMethod]
     public void Reference_Internal_Different_Before()
     {