From b0cde17bcea7b953f4f5d0c531c7c0998379a2c0 Mon Sep 17 00:00:00 2001
From: William Cory <williamcory@Williams-MacBook-Pro.local>
Date: Wed, 8 May 2024 11:56:34 -0700
Subject: [PATCH] feat: Make Address.toString() checksum

---
 packages/util/src/address.ts                    | 17 ++++++++++++++++-
 packages/util/test/address.spec.ts              | 11 ++++++-----
 .../util/test/testdata/eip1014Examples.json     | 12 ++++++------
 3 files changed, 28 insertions(+), 12 deletions(-)

diff --git a/packages/util/src/address.ts b/packages/util/src/address.ts
index 5fdf192df4..c1267f32ed 100644
--- a/packages/util/src/address.ts
+++ b/packages/util/src/address.ts
@@ -1,3 +1,5 @@
+import { keccak256 } from 'ethereum-cryptography/keccak.js'
+
 import {
   generateAddress,
   generateAddress2,
@@ -129,7 +131,20 @@ export class Address {
    * Returns hex encoding of address.
    */
   toString(): PrefixedHexString {
-    return bytesToHex(this.bytes)
+    const unprefixedString = bytesToHex(this.bytes).substring(2).split('')
+
+    const hash = keccak256(this.bytes)
+
+    for (let i = 0; i < 40; i += 2) {
+      if (hash[i >> 1] >> 4 >= 8 && unprefixedString[i]) {
+        unprefixedString[i] = unprefixedString[i].toUpperCase()
+      }
+      if ((hash[i >> 1] & 0x0f) >= 8 && unprefixedString[i + 1]) {
+        unprefixedString[i + 1] = unprefixedString[i + 1].toUpperCase()
+      }
+    }
+
+    return `0x${unprefixedString.join('')}`
   }
 
   /**
diff --git a/packages/util/test/address.spec.ts b/packages/util/test/address.spec.ts
index c0fc0b0e76..58abf28054 100644
--- a/packages/util/test/address.spec.ts
+++ b/packages/util/test/address.spec.ts
@@ -40,7 +40,7 @@ describe('Address', () => {
     const pubKey = hexToBytes(
       '0x3a443d8381a6798a70c6ff9304bdc8cb0163c23211d11628fae52ef9e0dca11a001cf066d56a8156fc201cd5df8a36ef694eecd258903fca7086c1fae7441e1d'
     )
-    const str = '0x2f015c60e0be116b1f0cd534704db9c92118fb6a'
+    const str = '0x2f015c60E0BE116b1f0cd534704Db9c92118FB6a'
     const addr = Address.fromPublicKey(pubKey)
     assert.equal(addr.toString(), str)
   })
@@ -55,7 +55,7 @@ describe('Address', () => {
   it('should instantiate from private key', () => {
     // prettier-ignore
     const privateKey = Uint8Array.from([234, 84, 189, 197, 45, 22, 63, 136, 201, 58, 176, 97, 87, 130, 207, 113, 138, 46, 251, 158, 81, 167, 152, 154, 171, 27, 8, 6, 126, 156, 28, 95])
-    const str = '0x2f015c60e0be116b1f0cd534704db9c92118fb6a'
+    const str = '0x2f015c60E0BE116b1f0cd534704Db9c92118FB6a'
     const addr = Address.fromPrivateKey(privateKey)
     assert.equal(addr.toString(), str)
   })
@@ -63,10 +63,10 @@ describe('Address', () => {
   it('should generate address for created contract', () => {
     const from = Address.fromString('0x990ccf8a0de58091c028d6ff76bb235ee67c1c39')
     const addr = Address.generate(from, BigInt(14))
-    assert.equal(addr.toString(), '0xd658a4b8247c14868f3c512fa5cbb6e458e4a989')
+    assert.equal(addr.toString(), '0xd658a4b8247C14868F3c512fa5cBB6e458e4A989')
 
     const addr2 = Address.generate(from, BigInt(0))
-    assert.equal(addr2.toString(), '0xbfa69ba91385206bfdd2d8b9c1a5d6c10097a85b')
+    assert.equal(addr2.toString(), '0xbFA69bA91385206BFdD2D8B9c1a5d6C10097a85b')
   })
 
   it('should provide correct precompile check', () => {
@@ -94,10 +94,11 @@ describe('Address', () => {
 
   it('should provide a Uint8Array that does not mutate the original address', () => {
     const str = '0x2f015c60e0be116b1f0cd534704db9c92118fb6a'
+    const checksumStr = '0x2f015c60E0BE116b1f0cd534704Db9c92118FB6a'
     const address = Address.fromString(str)
     const addressBytes = address.toBytes()
     addressBytes.fill(0)
-    assert.equal(address.toString(), str)
+    assert.equal(address.toString(), checksumStr)
   })
 
   it('should compare equality properly', () => {
diff --git a/packages/util/test/testdata/eip1014Examples.json b/packages/util/test/testdata/eip1014Examples.json
index 18779b0509..d611abcdf0 100644
--- a/packages/util/test/testdata/eip1014Examples.json
+++ b/packages/util/test/testdata/eip1014Examples.json
@@ -13,7 +13,7 @@
     "salt": "0x0000000000000000000000000000000000000000000000000000000000000000",
     "initCode": "0x00",
     "gas": "32006",
-    "result": "0xb928f69bb1d91cd65274e3c79d8986362984fda3"
+    "result": "0xB928F69Bb1D91cD65274e3C79D8986362984FdA3"
   },
   {
     "comment": "Example 2",
@@ -21,7 +21,7 @@
     "salt": "0x000000000000000000000000feed000000000000000000000000000000000000",
     "initCode": "0x00",
     "gas": "32006",
-    "result": "0xd04116cdd17bebe565eb2422f2497e06cc1c9833"
+    "result": "0xD04116CdD17BEBE565EB2422F2497E06cc1c9833"
   },
   {
     "comment": "Example 3",
@@ -29,7 +29,7 @@
     "salt": "0x0000000000000000000000000000000000000000000000000000000000000000",
     "initCode": "0xdeadbeef",
     "gas": "32006",
-    "result": "0x70f2b2914a2a4b783faefb75f459a580616fcb5e"
+    "result": "0x70f2B2914A2a4b783FAEfb75f459a580616fCb5e"
   },
   {
     "comment": "Example 4",
@@ -37,7 +37,7 @@
     "salt": "0x00000000000000000000000000000000000000000000000000000000cafebabe",
     "initCode": "0xdeadbeef",
     "gas": "32006",
-    "result": "0x60f3f640a8508fc6a86d45df051962668e1e8ac7"
+    "result": "0x60f3F640a8508Fc6a86D45dF051962668e1e8ac7"
   },
   {
     "comment": "Example 5",
@@ -45,7 +45,7 @@
     "salt": "0x00000000000000000000000000000000000000000000000000000000cafebabe",
     "initCode": "0xdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef",
     "gas": "32012",
-    "result": "0x1d8bfdc5d46dc4f61d6b6115972536ebe6a8854c"
+    "result": "0x1D8BfDC5d46Dc4f61d6b6115972536ebe6A8854c"
   },
   {
     "comment": "Example 6",
@@ -53,6 +53,6 @@
     "salt": "0x0000000000000000000000000000000000000000000000000000000000000000",
     "initCode": "0x",
     "gas": "32000",
-    "result": "0xe33c0c7f7df4809055c3eba6c09cfe4baf1bd9e0"
+    "result": "0xE33c0c7F7Df4809055C3Eba6c09cfe4baF1BD9E0"
   }
 ]