Update docs

test/helpers/create.js

@@ -0,0 +1,22 @@
+const RLP = require('rlp');
+
+function computeCreateAddress(deployer, nonce) {
+  return web3.utils.toChecksumAddress(web3.utils.sha3(RLP.encode([deployer.address ?? deployer, nonce])).slice(-40));
+}
+
+function computeCreate2Address(saltHex, bytecode, deployer) {
+  return web3.utils.toChecksumAddress(
+    web3.utils
+      .sha3(
+        `0x${['ff', deployer.address ?? deployer, saltHex, web3.utils.soliditySha3(bytecode)]
+          .map(x => x.replace(/0x/, ''))
+          .join('')}`,
+      )
+      .slice(-40),
+  );
+}
+
+module.exports = {
+  computeCreateAddress,
+  computeCreate2Address,
+};