fmt

package.json

@@ -57,4 +57,4 @@
   "dependencies": {
     "@protobufjs/utf8": "^1.1.0"
   }
-}
+}

src/__tests__/index.test.ts

@@ -335,6 +335,21 @@ describe("number", () => {
     expect(deserialized.a).toEqual(3);
   });
 
+  test("u8 max", () => {
+    class Struct {
+      @field({ type: "u8" })
+      public a: number;
+
+      constructor(a: number) {
+        this.a = a;
+      }
+    }
+    const instance = new Struct(255);
+    const buf = serialize(instance);
+    const deserialized = deserialize(buf, Struct);
+    expect(deserialized.a).toEqual(255);
+  });
+
   test("u16", () => {
     class Struct {
       @field({ type: "u16" })

src/bigint.ts

@@ -94,7 +94,7 @@ export const readUInt16LE = (buffer: Uint8Array, offset: number) => {
 
 
 
-const checkInt = (value: number, min: number | bigint, max: number | bigint, byteLength: number) => {
+export const checkInt = (value: number, min: number | bigint, max: number | bigint, byteLength: number) => {
     if (value > max || value < min) {
         const n = typeof min === 'bigint' ? 'n' : '';
         let range;

src/binary.ts

@@ -1,4 +1,4 @@
-import { toBigIntLE, writeBufferLEBigInt, writeUInt32LE, readUInt32LE, readUInt16LE, writeUInt16LE, readBigUInt64LE, readUIntLE } from './bigint.js';
+import { toBigIntLE, writeBufferLEBigInt, writeUInt32LE, readUInt32LE, readUInt16LE, writeUInt16LE, readBigUInt64LE, readUIntLE, checkInt } from './bigint.js';
 import { BorshError } from "./error.js";
 import utf8 from '@protobufjs/utf8';
 
@@ -29,6 +29,7 @@ export class BinaryWriter {
 
   public u8(value: number) {
     this.maybeResize(1);
+    checkInt(value, 0, 255, 1);
     this._buf[this._length] = value;
     this._length += 1;
   }