Buffer management bug fix. Fixes #3.

Author: CXuesong

Luaon.NET/LuaTableTextReader.cs

@@ -228,18 +228,20 @@ private bool EnsureBuffer(int length = 0)
             {
                 // Shift unread chars to the left; reduce buffer length.
                 Array.Copy(buffer, bufferPos, buffer, 0, bufferLength - bufferPos);
-                bufferLength = bufferLength - bufferPos;
+                bufferLength -= bufferPos;
                 bufferPos = 0;
             }
             // Read from where the current loaded buffer ends.
             var charsRead = Reader.ReadBlock(buffer, bufferLength, charsNeeded);
             bufferLength += charsRead;
             if (charsRead < charsNeeded)
             {
+                // Reader must have reached EOF.
+                Debug.Assert(Reader.Peek() < 0);
                 readerEof = true;
                 return false;
             }
-            return false;
+            return true;
         }
 
         private bool LookAhead(char c)

XUnitTestProject1/Tests/RegressionTests.cs

@@ -35,5 +35,29 @@ public void Issue1(string seed, int repeat)
             Assert.Equal(bigTable.ToString(), bigTable2.ToString());
         }
 
+        /// <summary>
+        /// LUA table key being truncated by reader buffer boundary.
+        /// </summary>
+        [Theory]
+        [InlineData("0123456789ABCDEF", 3)]
+        [InlineData("0123456789ABCDEF", 10)]
+        [InlineData("0123456789ABCDEF", 64)]
+        [InlineData("0123456789ABCDEF", 100)]
+        public void Issue3(string seed, int repeat)
+        {
+            var bigTable = new LTable
+            {
+                ["Field1"] = 12345,
+                ["Field2"] = "Test",
+            };
+            for (var i = 0; i < repeat; i++)
+                bigTable["TestField" + i] = seed + i;
+            var serialized = bigTable.ToString(Formatting.Prettified);
+            Assert.Contains("12345", serialized);
+            Assert.Contains("Test", serialized);
+            var bigTable2 = LToken.Parse(serialized);
+            Assert.Equal(bigTable.ToString(), bigTable2.ToString());
+        }
+
     }
 }