Added Buffer to BNLike type, PrefixedHexString in types, use BNLike for ecrecover v and chainId input, added type tests

Author: holgerd77

src/bytes.ts

@@ -1,6 +1,6 @@
 import BN from 'bn.js'
 import { intToBuffer, stripHexPrefix, padToEven, isHexString, isHexPrefixed } from 'ethjs-util'
-import { TransformableToArray, TransformableToBuffer } from './types'
+import { PrefixedHexString, TransformableToArray, TransformableToBuffer } from './types'
 import { assertIsBuffer, assertIsArray, assertIsHexString } from './helpers'
 
 /**
@@ -112,7 +112,7 @@ export const unpadHexString = function(a: string): string {
  */
 export const toBuffer = function(
   v:
-    | string
+    | PrefixedHexString
     | number
     | BN
     | Buffer

src/signature.ts

@@ -3,6 +3,7 @@ import BN from 'bn.js'
 import { toBuffer, setLengthLeft, bufferToHex, bufferToInt } from './bytes'
 import { keccak } from './hash'
 import { assertIsBuffer } from './helpers'
+import { BNLike } from './types'
 
 export interface ECDSASignature {
   v: number
@@ -30,7 +31,7 @@ export const ecsign = function(
   return ret
 }
 
-function calculateSigRecovery(v: number | BN | Buffer, chainId?: number | BN | Buffer): BN {
+function calculateSigRecovery(v: BNLike, chainId?: BNLike): BN {
   const vBN = new BN(toBuffer(v))
   const chainIdBN = chainId ? new BN(toBuffer(chainId)) : undefined
   return chainIdBN ? vBN.sub(chainIdBN.muln(2).addn(35)) : vBN.subn(27)
@@ -47,10 +48,10 @@ function isValidSigRecovery(recovery: number | BN): boolean {
  */
 export const ecrecover = function(
   msgHash: Buffer,
-  v: number | BN | Buffer,
+  v: BNLike,
   r: Buffer,
   s: Buffer,
-  chainId?: number | BN | Buffer
+  chainId?: BNLike
 ): Buffer {
   const signature = Buffer.concat([setLengthLeft(r, 32), setLengthLeft(s, 32)], 64)
   const recovery = calculateSigRecovery(v, chainId)

src/types.ts

@@ -5,7 +5,7 @@ import { unpadBuffer } from './bytes'
 /*
  * A type that represents a BNLike input that can be converted to a BN.
  */
-export type BNLike = BN | string | number
+export type BNLike = BN | PrefixedHexString | number | Buffer
 
 /*
  * A type that represents a BufferLike input that can be converted to a Buffer.
@@ -28,7 +28,7 @@ export type PrefixedHexString = string
  * A type that represents an Address-like value.
  * To convert to address, use `new Address(toBuffer(value))`
  */
-export type AddressLike = Address | Buffer | string
+export type AddressLike = Address | Buffer | PrefixedHexString
 
 /*
  * A type that represents an object that has a `toArray()` method.

test/signature.spec.ts

@@ -129,14 +129,27 @@ describe('ecrecover', function() {
       '8ae8cb685a7a9f29494b07b287c3f6a103b73fa178419d10d1184861a40f6afe',
       'hex'
     )
-    const v = Buffer.from('f2ded8deec6714', 'hex')
+
     const r = Buffer.from('ec212841e0b7aaffc3b3e33a08adf32fa07159e856ef23db85175a4f6d71dc0f', 'hex')
     const s = Buffer.from('4b8e02b96b94064a5aa2f8d72bd0040616ba8e482a5dd96422e38c9a4611f8d5', 'hex')
-    const chainID = Buffer.from('796f6c6f763378', 'hex')
-    const sender = ecrecover(msgHash, v, r, s, chainID)
-    assert.ok(sender.equals(senderPubKey), 'sender pubkey correct')
-    const chainIDNumber = parseInt(chainID.toString('hex'), 16)
-    const vNumber = parseInt(v.toString('hex'), 16)
+
+    const vBuffer = Buffer.from('f2ded8deec6714', 'hex')
+    const chainIDBuffer = Buffer.from('796f6c6f763378', 'hex')
+    let sender = ecrecover(msgHash, vBuffer, r, s, chainIDBuffer)
+    assert.ok(sender.equals(senderPubKey), 'sender pubkey correct (Buffer)')
+
+    const vBN = new BN(vBuffer)
+    const chainIDBN = new BN(chainIDBuffer)
+    sender = ecrecover(msgHash, vBN, r, s, chainIDBN)
+    assert.ok(sender.equals(senderPubKey), 'sender pubkey correct (BN)')
+
+    const vHexString = '0xf2ded8deec6714'
+    const chainIDHexString = '0x796f6c6f763378'
+    sender = ecrecover(msgHash, vHexString, r, s, chainIDHexString)
+    assert.ok(sender.equals(senderPubKey), 'sender pubkey correct (HexString)')
+
+    const chainIDNumber = parseInt(chainIDBuffer.toString('hex'), 16)
+    const vNumber = parseInt(vBuffer.toString('hex'), 16)
     assert.throws(() => {
       // If we would use numbers for the `v` and `chainId` parameters, then it should throw.
       // (The numbers are too high to perform arithmetic on)