[Implement] Buffer.readUInt8

Author: RedDwarfian

assembly/buffer/index.ts

@@ -22,4 +22,14 @@ export class Buffer extends Uint8Array {
  result.dataLength = size;
  return result;
  }
+
+ readInt8(offset: i32 = 0): i8 {
+ if(<u32>offset >= this.dataLength) throw new RangeError(E_INDEXOUTOFRANGE);
+ return load<i8>(this.dataStart + usize(offset));
+ }
+
+ readUInt8(offset: i32 = 0): u8 {
+ if(<u32>offset > this.dataLength) throw new RangeError(E_INDEXOUTOFRANGE);
+ return load<u8>(this.dataStart + usize(offset));
+ }
 }

assembly/node.d.ts

@@ -3,4 +3,7 @@ declare class Buffer extends Uint8Array {
  static alloc(size: i32): Buffer;
  /** This method allocates a new Buffer of indicated size. This is unsafe because the data is not zeroed. */
  static allocUnsafe(size: i32): Buffer;
+ /** Reads a signed integer at the designated offset. */
+ readInt8(offset?: i32): i8;
+ readUInt8(offset?: i32): u8;
 }

tests/buffer.spec.ts

@@ -42,4 +42,35 @@ describe("buffer", () => {
  // TODO: expectFn(() => { Buffer.allocUnsafe(-1); }).toThrow();
  // TODO: expectFn(() => { Buffer.allocUnsafe(BLOCK_MAXSIZE + 1); }).toThrow();
  });
+
+ test("#readInt8", () => {
+ let buff = new Buffer(10);
+ buff[0] = 5;
+ buff[9] = 255;
+ expect<i8>(buff.readInt8(0)).toBe(5);
+ expect<i8>(buff.readInt8()).toBe(5);
+ // Testing offset, and casting between u8 and i8.
+ expect<i8>(buff.readInt8(9)).toBe(-1);
+ // TODO:
+ // expectFn(() => { 
+ // let newBuff = new Buffer(1);
+ // newBuff.readInt8(5);
+ // }).toThrow();
+ });
+
+ test("#readUInt8", () => {
+ let buff = new Buffer(10);
+ buff[0] = -2;
+ buff[9] = 47;
+ // Testing casting between u8 and i8.
+ expect<u8>(buff.readUInt8(0)).toBe(254);
+ expect<u8>(buff.readUInt8()).toBe(254);
+ // Testing offset
+ expect<u8>(buff.readUInt8(9)).toBe(47);
+ // TODO:
+ // expectFn(() => { 
+ // let newBuff = new Buffer(1);
+ // newBuff.readUInt8(5);
+ // }).toThrow(); 
+ });
 });