Add a BigInt package for browsers that do not support BigInt

package.json

@@ -1,6 +1,6 @@
 {
   "name": "boa-sdk-ts",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "The TypeScript BOA SDK libary",
   "main": "lib/index.js",
   "types": "lib/index.d.ts",
@@ -29,6 +29,7 @@
     "@ctrl/ts-base32": "^1.2.1",
     "axios": "^0.19.2",
     "crc": "^3.8.0",
+    "jsbi": "^3.1.3",
     "lodash": "^4.17.19",
     "randombytes": "^2.1.0",
     "sodium-javascript": "^0.6.1",

src/index.ts

@@ -21,3 +21,7 @@ export { Signature } from './modules/data/Signature';
 export { Validator } from './modules/data/Validator';
 
 export { BOAClient } from './modules/net/BOAClient';
+
+// For BinInt
+import { default as JSBInt } from 'jsbi';
+export { JSBInt };

src/modules/data/Hash.ts

@@ -13,6 +13,7 @@
 
 import * as sodium from 'sodium-javascript'
 import {readFromString, writeToString} from "../utils/buffer"
+import JSBI from 'jsbi';
 
 /**
  * The Class for creating hash
@@ -91,27 +92,42 @@ export function hashMulti (source1: Buffer, source2: Buffer): Hash
 
 /**
  * Makes a UTXOKey
- * @param h Hash of transaction
- * @param index Index of the output
+ * @param h {Hash} Hash of transaction
+ * @param index {number | string} Index of the output
  * @returns Instance of Hash
  * See_Also https://github.com/bpfkorea/agora/blob/v0.x.x/source/agora/consensus/data/UTXOSetValue.d#L50-L53
  */
-export function makeUTXOKey (h: Hash, index: bigint): Hash
+export function makeUTXOKey (h: Hash, index: number | string | object): Hash
 {
     let buf = Buffer.alloc(8);
 
     // See https://github.com/nodejs/node/blob/
     // 88fb5a5c7933022de750745e51e5dc0996a1e2c4/lib/internal/buffer.js#L573-L592
-    let lo = Number(index & BigInt(0xffffffff));
+    let lo = 
+            JSBI.toNumber(
+                JSBI.bitwiseAnd(
+                    JSBI.BigInt(index), 
+                    JSBI.BigInt(0xffffffff)
+                )
+            );
     buf[0] = lo;
     lo = lo >> 8;
     buf[1] = lo;
     lo = lo >> 8;
     buf[2] = lo;
     lo = lo >> 8;
     buf[3] = lo;
-
-    let hi = Number(index >> BigInt(32) & BigInt(0xffffffff));
+
+    let hi = 
+            JSBI.toNumber(
+                JSBI.bitwiseAnd(
+                    JSBI.signedRightShift(
+                        JSBI.BigInt(index), 
+                        JSBI.BigInt(32)
+                    ), 
+                    JSBI.BigInt(0xffffffff)
+                )
+            );
     buf[4] = hi;
     hi = hi >> 8;
     buf[5] = hi;

tests/Hash.test.ts

@@ -13,6 +13,7 @@
 
 import * as assert from 'assert';
 import * as boasdk from '../lib';
+import { default as JSBI } from 'jsbi';
 
 describe('Hash', () => {
     // Buffer has the same content. However, when printed with hex strings,
@@ -61,7 +62,8 @@ describe('Hash', () => {
         let tx_hash = new boasdk.Hash();
         tx_hash.fromString('0x5d7f6a7a30f7ff591c8649f61eb8a35d034824ed5cd252c2c6f10cdbd223671' +
             '3dc369ef2a44b62ba113814a9d819a276ff61582874c9aee9c98efa2aa1f10d73');
-        let hash = boasdk.makeUTXOKey(tx_hash, BigInt(1));
+        //let hash = boasdk.makeUTXOKey(tx_hash, JSBI.BigInt(1));
+        let hash = boasdk.makeUTXOKey(tx_hash, boasdk.JSBInt.BigInt(1));
         assert.equal(hash,
             '0x7c95c29b184e47fbd32e58e5abd42c6e22e8bd5a7e934ab049d21df545e09c2' +
             'e33bb2b89df2e59ee01eb2519b1508284b577f66a76d42546b65a6813e592bb84');