Fix bigint encoding

Author: lxsmnsyc

packages/seroval/src/binary/deserializer.ts

@@ -185,7 +185,7 @@ async function deserializeRef(
 ) {
   const ref = await deserializeUint(ctx);
   if (expected != null) {
-    const marker = ctx.marker.get(expected);
+    const marker = ctx.marker.get(ref);
     if (marker == null) {
       throw new SerovalMalformedBinaryTypeError(type);
     }
@@ -225,6 +225,7 @@ async function deserializeString(ctx: DeserializerContext) {
 
 async function deserializeBigint(ctx: DeserializerContext) {
   const id = await deserializeId(ctx, SerovalBinaryType.BigInt);
+  const sign = await deserializeByte(ctx);
   // Check if the value exists
   const current = (
     await deserializeRef(
@@ -233,7 +234,8 @@ async function deserializeBigint(ctx: DeserializerContext) {
       SerovalBinaryType.String,
     )
   ).value;
-  upsert(ctx, id, decodeBigint(current as string));
+  const value = decodeBigint(current as string);
+  upsert(ctx, id, sign ? -value : value);
 }
 
 async function deserializeWKSymbol(ctx: DeserializerContext) {

packages/seroval/src/binary/encoder.ts

@@ -98,7 +98,7 @@ export function decodeBigint(value: string): bigint {
   let hex = '';
   for (let i = 0, len = value.length; i < len; i++) {
     const code = value.charCodeAt(i);
-    hex += code.toString(16);
+    hex += code.toString(16).padStart(2, '0');
   }
   return BigInt('0x' + hex);
 }

packages/seroval/src/binary/nodes.ts

@@ -118,6 +118,7 @@ export type SerovalStringNode = [
 export type SerovalBigintNode = [
   type: SerovalBinaryType.BigInt,
   id: Uint8Array,
+  isNegative: number,
   // value ref
   value: Uint8Array,
 ];

packages/seroval/src/binary/serializer.ts

@@ -177,7 +177,8 @@ function serializeBigInt(ctx: SerializerContext, value: bigint) {
   onSerialize(ctx, [
     SerovalBinaryType.BigInt,
     id,
-    serialize(ctx, encodeBigint(value)),
+    value < 0 ? 1 : 0,
+    serialize(ctx, encodeBigint(value < 0 ? -value : value)),
   ]);
   return id;
 }