fix: StoreSlice must copy bits and refs

Author: justdmitry

TonLibDotNet.Tests/Cells/CellBuilderTests.cs

@@ -226,5 +226,24 @@ public void WritesStringChunkedOk()
 
             slice.EndRead();
         }
+
+        [Fact]
+        public void StoreSliceStoresBitsAndRefs()
+        {
+            var original = new CellBuilder()
+                .StoreUInt(11, 32)
+                .StoreUInt(12, 32)
+                .StoreRef(new CellBuilder().StoreBit(true))
+                .StoreRef(new CellBuilder().StoreBit(false))
+                .Build()
+                .BeginRead();
+
+            Assert.Equal((uint)11, original.LoadUInt(32));
+            Assert.True(original.LoadRef().BeginRead().LoadBit());
+
+            var slice = new CellBuilder().StoreSlice(original).Build().BeginRead();
+            Assert.Equal((uint)12, slice.LoadUInt(32));
+            Assert.False(slice.LoadRef().BeginRead().LoadBit());
+        }
     }
 }

TonLibDotNet/Cells/CellBuilder.cs

@@ -58,9 +58,18 @@ public CellBuilder StoreBits(ReadOnlySpan<bool> values)
 
         public CellBuilder StoreSlice(Slice value)
         {
-            EnsureCanStore(value.Length);
-            value.LoadBitsTo(data.AsSpan(Length, value.Length));
-            Length += value.Length;
+            var len = value.Length;
+            EnsureCanStore(len);
+            value.LoadBitsTo(data.AsSpan(Length, len));
+            Length += len;
+
+            var rf = value.TryLoadRef();
+            while (rf != null)
+            {
+                StoreRef(rf);
+                rf = value.TryLoadRef();
+            }
+
             return this;
         }