Fix #6, testsuite implemented.

lib/nbt/Stream.dart

@@ -155,16 +155,20 @@ class ByteLayer {
 
   void writeFloat(double value) {
     _ensureCapacity(4);
+    // Round the float to 8 decimal places before writing
+    value = double.parse(value.toStringAsFixed(8));
     _byteBuffer.buffer.asByteData().setFloat32(_position, value, Endian.big);
-    _position += 2;
+    _position += 4;
   }
 
   double readFloat() {
     final value =
         _byteBuffer.buffer.asByteData().getFloat32(_position, Endian.big);
 
-    _position += 2;
-    return value;
+    _position += 4;
+
+    // Round the float to 8 decimal places after reading
+    return double.parse(value.toStringAsFixed(8));
   }
 
   void writeTagName(String name) {
@@ -234,4 +238,49 @@ class ByteLayer {
     _position += 8;
     return value;
   }
+
+  void writeVarLongNoZigZag(int value) {
+    while (true) {
+      if ((value & ~0x7F) == 0) {
+        writeByte(value);
+        return;
+      }
+      writeByte((value & 0x7F) | 0x80);
+      value = value >> 7;
+    }
+  }
+
+  void writeVarLongZigZag(int value) {
+    value = (value << 1) ^ (value >> 63);
+    writeVarLongNoZigZag(value);
+  }
+
+  void writeLongZigZag(int value) {
+    value = (value << 1) & (value >> 63);
+    _byteBuffer.buffer.asByteData().setInt64(_position, value, Endian.big);
+  }
+
+  int readVarLongNoZigZag() {
+    int result = 0;
+    int shift = 0;
+    int b;
+
+    do {
+      b = readByte();
+      result |= (b & 0x7F) << shift;
+      shift += 7;
+    } while ((b & 0x80) != 0);
+
+    return result;
+  }
+
+  int readVarLongZigZag() {
+    int result = readVarLongNoZigZag();
+    return (result >> 1) ^ -(result & 1);
+  }
+
+  int readLongZigZag() {
+    int value = readLong();
+    return (value >> 1) ^ (-(value & 1));
+  }
 }