Use browser friendly hexToBytes, bytesToHex methods

src/blst/privateKey.ts

@@ -1,5 +1,5 @@
 import * as blst from "@chainsafe/blst";
-import {bytesToHex, hexToBytes, randomBytes} from "../helpers/utils";
+import {bytesToHex, hexToBytes, randomBytes} from "../helpers";
 import {SECRET_KEY_LENGTH} from "../constants";
 import {IPrivateKey} from "../interface";
 import {PublicKey} from "./publicKey";

src/blst/publicKey.ts

@@ -1,5 +1,5 @@
 import * as blst from "@chainsafe/blst";
-import {bytesToHex, hexToBytes} from "../helpers/utils";
+import {bytesToHex, hexToBytes} from "../helpers";
 import {IPublicKey} from "../interface";
 import {Signature} from "./signature";
 

src/blst/signature.ts

@@ -1,5 +1,5 @@
 import * as blst from "@chainsafe/blst";
-import {bytesToHex, hexToBytes} from "../helpers/utils";
+import {bytesToHex, hexToBytes} from "../helpers";
 import {ISignature} from "../interface";
 import {PublicKey} from "./publicKey";
 

src/helpers/hex.ts

@@ -0,0 +1,38 @@
+/**
+ * Browser compatible fromHex method
+ * From https://github.com/herumi/bls-eth-wasm/blob/04eedb77aa96e66b4f65a0ab477228adf8090c36/src/bls.js#L62
+ */
+export function hexToBytes(hex: string): Uint8Array {
+  if (hex.startsWith("0x")) {
+    hex = hex.slice(2);
+  }
+
+  if (hex.length & 1) {
+    throw Error("hexToBytes:length must be even " + hex.length);
+  }
+
+  const n = hex.length / 2;
+  const a = new Uint8Array(n);
+
+  for (let i = 0; i < n; i++) {
+    a[i] = parseInt(hex.slice(i * 2, i * 2 + 2), 16);
+  }
+
+  return a;
+}
+
+/**
+ * Browser compatible toHex method
+ * From https://github.com/herumi/bls-eth-wasm/blob/04eedb77aa96e66b4f65a0ab477228adf8090c36/src/bls.js#L50
+ */
+export function bytesToHex(bytes: Uint8Array): string {
+  // return "0x" + Buffer.from(bytes).toString("hex");
+  let s = "";
+  const n = bytes.length;
+
+  for (let i = 0; i < n; i++) {
+    s += ("0" + bytes[i].toString(16)).slice(-2);
+  }
+
+  return "0x" + s;
+}

src/helpers/index.ts

@@ -1 +1,2 @@
+export * from "./hex";
 export * from "./utils";

src/helpers/utils.ts

@@ -9,14 +9,6 @@ export function assert(condition: unknown, message = "Assertion failed"): assert
   }
 }
 
-export function hexToBytes(hex: string): Uint8Array {
-  return Buffer.from(hex.replace("0x", ""), "hex");
-}
-
-export function bytesToHex(bytes: Uint8Array): string {
-  return "0x" + Buffer.from(bytes).toString("hex");
-}
-
 export function isEqualBytes(a: Buffer | Uint8Array, b: Buffer | Uint8Array): boolean {
   return toBuffer(a).equals(toBuffer(b));
 }

src/herumi/privateKey.ts

@@ -5,7 +5,7 @@ import {SECRET_KEY_LENGTH} from "../constants";
 import {getContext} from "./context";
 import {PublicKey} from "./publicKey";
 import {Signature} from "./signature";
-import {bytesToHex, hexToBytes} from "../helpers/utils";
+import {bytesToHex, hexToBytes} from "../helpers";
 import {IPrivateKey} from "../interface";
 
 export class PrivateKey implements IPrivateKey {

src/herumi/publicKey.ts

@@ -2,7 +2,7 @@ import {PublicKeyType} from "bls-eth-wasm";
 import {getContext} from "./context";
 import {EMPTY_PUBLIC_KEY} from "../constants";
 import {Signature} from "./signature";
-import {bytesToHex, hexToBytes, isEqualBytes} from "../helpers/utils";
+import {bytesToHex, hexToBytes, isEqualBytes} from "../helpers";
 import {IPublicKey} from "../interface";
 
 export class PublicKey implements IPublicKey {

src/herumi/signature.ts

@@ -3,7 +3,7 @@ import {SIGNATURE_LENGTH, EMPTY_SIGNATURE} from "../constants";
 import {SignatureType} from "bls-eth-wasm";
 import {getContext} from "./context";
 import {PublicKey} from "./publicKey";
-import {bytesToHex, hexToBytes, isEqualBytes} from "../helpers/utils";
+import {bytesToHex, hexToBytes, isEqualBytes} from "../helpers";
 import {ISignature} from "../interface";
 
 export class Signature implements ISignature {

test/spec/aggregate_sigs.test.ts

@@ -1,6 +1,6 @@
 import path from "path";
 import {describeDirectorySpecTest, InputType} from "@chainsafe/lodestar-spec-test-util";
-import {bytesToHex, hexToBytes} from "../../src/helpers/utils";
+import {bytesToHex, hexToBytes} from "../../src/helpers";
 import {SPEC_TESTS_DIR} from "../params";
 import {describeForAllImplementations} from "../switch";
 

test/spec/aggregate_sigs_verify.test.ts

@@ -1,6 +1,6 @@
 import path from "path";
 import {describeDirectorySpecTest, InputType} from "@chainsafe/lodestar-spec-test-util";
-import {hexToBytes} from "../../src/helpers/utils";
+import {hexToBytes} from "../../src/helpers";
 import {SPEC_TESTS_DIR} from "../params";
 import {describeForAllImplementations} from "../switch";
 

test/spec/fast_aggregate_verify.test.ts

@@ -1,6 +1,6 @@
 import path from "path";
 import {describeDirectorySpecTest, InputType} from "@chainsafe/lodestar-spec-test-util";
-import {hexToBytes} from "../../src/helpers/utils";
+import {hexToBytes} from "../../src/helpers";
 import {SPEC_TESTS_DIR} from "../params";
 import {describeForAllImplementations} from "../switch";
 

test/spec/sign.test.ts

@@ -1,6 +1,6 @@
 import path from "path";
 import {describeDirectorySpecTest, InputType} from "@chainsafe/lodestar-spec-test-util";
-import {bytesToHex, hexToBytes} from "../../src/helpers/utils";
+import {bytesToHex, hexToBytes} from "../../src/helpers";
 import {SPEC_TESTS_DIR} from "../params";
 import {describeForAllImplementations} from "../switch";
 

test/spec/verify.test.ts

@@ -1,6 +1,6 @@
 import path from "path";
 import {describeDirectorySpecTest, InputType} from "@chainsafe/lodestar-spec-test-util";
-import {hexToBytes} from "../../src/helpers/utils";
+import {hexToBytes} from "../../src/helpers";
 import {SPEC_TESTS_DIR} from "../params";
 import {describeForAllImplementations} from "../switch";
 

test/unit/helpers/hex.test.ts

@@ -0,0 +1,29 @@
+import {expect} from "chai";
+import {hexToBytes, bytesToHex} from "../../../src/helpers/hex";
+
+describe("helpers / hex", () => {
+  const testCases: {id: string; hex: string}[] = [
+    {
+      id: "pubkey",
+      hex: "0xb6f21199594b56d77670564bf422cb331d5281ca2c1f9a45588a56881d8287ef8619efa6456d6cd2ef61306aa5b21311",
+    },
+  ];
+
+  for (const {id, hex} of testCases) {
+    it(`${id} hexToBytes`, () => {
+      const expectedBytes = hexToBytesNode(hex);
+      const bytes = hexToBytes(hex);
+      expect(expectedBytes.equals(bytes)).to.be.true;
+    });
+
+    it(`${id} bytesToHex`, () => {
+      const bytes = hexToBytesNode(hex);
+      const _hex = bytesToHex(bytes);
+      expect(_hex).to.equal(hex);
+    });
+  }
+});
+
+function hexToBytesNode(hex: string): Buffer {
+  return Buffer.from(hex.replace("0x", ""), "hex");
+}

test/unit/privateKey.test.ts

@@ -16,7 +16,7 @@ export function runPrivateKeyTests(bls: IBls): void {
     });
 
     it("should export private key to hex string from non-prefixed hex", () => {
-      expect(bls.PrivateKey.fromHex(privateKey.replace("0x", "")).toHex()).to.be.equal(privateKey);
+      expect(bls.PrivateKey.fromHex(privateKey).toHex()).to.be.equal(privateKey);
     });
 
     it("should not accept too short private key", () => {

test/unit/publicKey.test.ts

@@ -11,7 +11,7 @@ export function runPublicKeyTests(bls: IBls): void {
     });
 
     it("should export public key to hex string from non-prefixed hex", () => {
-      expect(bls.PublicKey.fromHex(publicKey.replace("0x", "")).toHex()).to.be.equal(publicKey);
+      expect(bls.PublicKey.fromHex(publicKey).toHex()).to.be.equal(publicKey);
     });
 
     it("from private key", () => {

test/util.ts

@@ -1,13 +1,5 @@
 import {randomBytes} from "../src/helpers";
 
-export function fromHexString(hex: string): Uint8Array {
-  return Buffer.from(hex.replace("0x", ""), "hex");
-}
-
-export function toHexString(bytes: Buffer | Uint8Array): string {
-  return `0x${Buffer.from(bytes).toString("hex")}`;
-}
-
 export function randomMessage(): Uint8Array {
   return randomBytes(32);
 }