Merge pull request #16 from solana-developers/make-keypairs

add: makeKeypairs()

README.md

@@ -6,6 +6,8 @@ Eventually most of these will end up in `@solana/web3.js`.
 
 ## What can I do with this module?
 
+[Make multiple keypairs at once](#makekeypairs-amount)
+
 [Resolve a custom error message](#getcustomerrormessageprogramerrors-errormessage)
 
 [Get an airdrop, and wait until it's confirmed](#requestandconfirmairdropconnection-publickey-lamports)
@@ -28,6 +30,14 @@ npm i @solana-developers/helpers
 
 ## helpers for the browser and node.js
 
+### makeKeypairs(amount)
+
+In some situations - like making tests for your on-chain programs - you might need to make lots of keypairs at once. You can use `makeKeypairs()` combined with JS destructuring to quickly create multiple variables with distinct keypairs.
+
+```typescript
+const [sender, recipient] = makeKeypairs(2);
+```
+
 ### getCustomErrorMessage(programErrors, errorMessage)
 
 Sometimes Solana libaries return an error like:

src/index.test.ts

@@ -7,6 +7,7 @@ import {
   requestAndConfirmAirdrop,
   requestAndConfirmAirdropIfRequired,
   getExplorerLink,
+  makeKeypairs,
 } from "./index";
 import { Connection, Keypair, LAMPORTS_PER_SOL } from "@solana/web3.js";
 import assert from "node:assert/strict";
@@ -286,3 +287,10 @@ describe("getExplorerLink", () => {
     assert.equal(link, "https://explorer.solana.com/block/241889720");
   });
 });
+
+describe("makeKeypairs", () => {
+  test("makeKeypairs() creates the correct number of keypairs", () => {
+    const keypairs = makeKeypairs(3);
+    assert.equal(keypairs.length, 3);
+  });
+});

src/index.ts

@@ -182,3 +182,8 @@ export const requestAndConfirmAirdropIfRequired = async (
   }
   return balance;
 };
+
+// Shout out to deanmlittle for this technique
+export const makeKeypairs = (amount: number): Array<Keypair> => {
+  return Array.from({ length: amount }, () => Keypair.generate());
+};