feat(batch2): verify memstore remainder features

dotnet/src/ZB.MOM.NatsNet.Server/JetStream/MemStore.cs

@@ -103,6 +103,23 @@ public sealed class JetStreamMemStore : IStreamStore
             _scheduling = new MsgScheduling(RunMsgScheduling);
     }
 
+    /// <summary>
+    /// Factory that mirrors Go <c>newMemStore</c> mapping semantics.
+    /// </summary>
+    public static JetStreamMemStore NewMemStore(StreamConfig cfg)
+    {
+        var ms = new JetStreamMemStore(cfg);
+
+        if (cfg.FirstSeq > 0)
+        {
+            var (_, err) = ms.PurgeInternal(cfg.FirstSeq);
+            if (err != null)
+                throw err;
+        }
+
+        return ms;
+    }
+
     // -----------------------------------------------------------------------
     // IStreamStore — store / load
     // -----------------------------------------------------------------------
@@ -1133,17 +1150,7 @@ public sealed class JetStreamMemStore : IStreamStore
         _mu.EnterReadLock();
         try
         {
-            if (_msgs == null || _msgs.Count == 0) return (Array.Empty<ulong>(), null);
+            return AllLastSeqsLocked();
-            var seqs = new List<ulong>(_fss.Size());
-            _fss.IterFast((subj, ss) =>
-            {
-                if (ss.LastNeedsUpdate)
-                    RecalculateForSubj(Encoding.UTF8.GetString(subj), ss);
-                seqs.Add(ss.Last);
-                return true;
-            });
-            seqs.Sort();
-            return (seqs.ToArray(), null);
         }
         finally
         {
@@ -1151,6 +1158,27 @@ public sealed class JetStreamMemStore : IStreamStore
         }
     }
 
+    /// <summary>
+    /// Returns sorted per-subject last sequences without taking locks.
+    /// Mirrors Go <c>allLastSeqsLocked</c>.
+    /// </summary>
+    private (ulong[] Seqs, Exception? Error) AllLastSeqsLocked()
+    {
+        if (_msgs == null || _msgs.Count == 0) return (Array.Empty<ulong>(), null);
+
+        var seqs = new List<ulong>(_fss.Size());
+        _fss.IterFast((subj, ss) =>
+        {
+            if (ss.LastNeedsUpdate)
+                RecalculateForSubj(Encoding.UTF8.GetString(subj), ss);
+            seqs.Add(ss.Last);
+            return true;
+        });
+
+        seqs.Sort();
+        return (seqs.ToArray(), null);
+    }
+
     /// <inheritdoc/>
     public (ulong[] Seqs, Exception? Error) MultiLastSeqs(string[] filters, ulong maxSeq, int maxAllowed)
     {

dotnet/tests/ZB.MOM.NatsNet.Server.Tests/JetStream/JetStreamMemoryStoreTests.cs

@@ -32,7 +32,7 @@ public class JetStreamMemoryStoreTests
     private static JetStreamMemStore NewMemStore(StreamConfig? cfg = null)
     {
         cfg ??= new StreamConfig { Storage = StorageType.MemoryStorage, Name = "test" };
-        return new JetStreamMemStore(cfg);
+        return JetStreamMemStore.NewMemStore(cfg);
     }
 
     private static byte[] Bytes(string s) => Encoding.UTF8.GetBytes(s);
@@ -41,6 +41,71 @@ public class JetStreamMemoryStoreTests
     private static ulong MsgSize(string subj, byte[]? hdr, byte[]? msg)
         => (ulong)(subj.Length + (hdr?.Length ?? 0) + (msg?.Length ?? 0) + 16);
 
+    [Fact]
+    public void NewMemStore_FactoryMethod_InitializesFirstSequence()
+    {
+        var method = typeof(JetStreamMemStore).GetMethod(
+            "NewMemStore",
+            System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.NonPublic);
+        method.ShouldNotBeNull();
+
+        var cfg = new StreamConfig
+        {
+            Name = "factory-init",
+            Storage = StorageType.MemoryStorage,
+            FirstSeq = 1000,
+        };
+
+        var created = method!.Invoke(null, new object?[] { cfg });
+        created.ShouldBeOfType<JetStreamMemStore>();
+
+        var ms = (JetStreamMemStore)created!;
+        var state = ms.State();
+        state.FirstSeq.ShouldBe(1000UL);
+        state.LastSeq.ShouldBe(999UL);
+        ms.Stop();
+    }
+
+    [Fact]
+    public void AllLastSeqsLocked_MatchesPublicAllLastSeqsOrdering()
+    {
+        var cfg = new StreamConfig
+        {
+            Name = "locked-all-last-seqs",
+            Subjects = new[] { "*.*" },
+            MaxMsgsPer = 50,
+            Storage = StorageType.MemoryStorage,
+        };
+        var ms = NewMemStore(cfg);
+
+        var subjs = new[] { "foo.foo", "foo.bar", "foo.baz", "bar.foo", "bar.bar", "bar.baz" };
+        var msg = Bytes("abc");
+        var rng = new Random(11);
+
+        for (var i = 0; i < 1_000; i++)
+        {
+            var subj = subjs[rng.Next(subjs.Length)];
+            ms.StoreMsg(subj, null, msg, 0);
+        }
+
+        var method = typeof(JetStreamMemStore).GetMethod(
+            "AllLastSeqsLocked",
+            System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic);
+        method.ShouldNotBeNull();
+
+        var result = method!.Invoke(ms, Array.Empty<object>());
+        result.ShouldNotBeNull();
+        var (lockedSeqs, lockedErr) = ((ValueTuple<ulong[], Exception?>)result!);
+
+        var (publicSeqs, publicErr) = ms.AllLastSeqs();
+
+        lockedErr.ShouldBeNull();
+        publicErr.ShouldBeNull();
+        lockedSeqs.SequenceEqual(publicSeqs).ShouldBeTrue();
+
+        ms.Stop();
+    }
+
     // -----------------------------------------------------------------------
     // TestMemStoreBasics (T:2023)
     // -----------------------------------------------------------------------

dotnet/tests/ZB.MOM.NatsNet.Server.Tests/JetStream/StorageEngineTests.cs

@@ -33,7 +33,7 @@ public class StorageEngineTests
     private static JetStreamMemStore NewMemStore(StreamConfig cfg)
     {
         cfg.Storage = StorageType.MemoryStorage;
-        return new JetStreamMemStore(cfg);
+        return JetStreamMemStore.NewMemStore(cfg);
     }
 
     private static byte[] Bytes(string s) => Encoding.UTF8.GetBytes(s);

reports/current.md

@@ -1,6 +1,6 @@
 # NATS .NET Porting Status Report
 
-Generated: 2026-02-28 12:11:43 UTC
+Generated: 2026-02-28 12:17:02 UTC
 
 ## Modules (12 total)
 
@@ -12,10 +12,10 @@ Generated: 2026-02-28 12:11:43 UTC
 
 | Status | Count |
 |--------|-------|
-| deferred | 2361 |
+| deferred | 2359 |
 | n_a | 24 |
 | stub | 1 |
-| verified | 1287 |
+| verified | 1289 |
 
 ## Unit Tests (3257 total)
 
@@ -34,4 +34,4 @@ Generated: 2026-02-28 12:11:43 UTC
 
 ## Overall Progress
 
-**2489/6942 items complete (35.9%)**
+**2491/6942 items complete (35.9%)**

reports/report_1a0ac59.md

@@ -0,0 +1,37 @@
+# NATS .NET Porting Status Report
+
+Generated: 2026-02-28 12:17:02 UTC
+
+## Modules (12 total)
+
+| Status | Count |
+|--------|-------|
+| verified | 12 |
+
+## Features (3673 total)
+
+| Status | Count |
+|--------|-------|
+| deferred | 2359 |
+| n_a | 24 |
+| stub | 1 |
+| verified | 1289 |
+
+## Unit Tests (3257 total)
+
+| Status | Count |
+|--------|-------|
+| deferred | 2091 |
+| n_a | 187 |
+| verified | 979 |
+
+## Library Mappings (36 total)
+
+| Status | Count |
+|--------|-------|
+| mapped | 36 |
+
+
+## Overall Progress
+
+**2491/6942 items complete (35.9%)**