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LiteSVM (NodeJS)

This is the NodeJS wrapper for LiteSVM. It brings best-in-class Solana testing to NodeJS, giving you a powerful, fast and ergonomic way to test Solana programs in TS/JS.

For a standard testing workflow, LiteSVM offers an experience superior to solana-test-validator (slow, unwieldy) and bankrun (reasonably fast and powerful, but inherits a lot of warts from solana-program-test).

Minimal example

This example just transfers lamports from Alice to Bob without loading any programs of our own. It uses the Node.js test runner.

import { test } from "node:test";
import assert from "node:assert/strict";
import { FailedTransactionMetadata, LiteSVM } from "litesvm";
import { getTransferSolInstruction } from "@solana-program/system";
import {
	appendTransactionMessageInstruction,
	createTransactionMessage,
	generateKeyPairSigner,
	lamports,
	pipe,
	setTransactionMessageFeePayerSigner,
	setTransactionMessageLifetimeUsingBlockhash,
	signTransactionMessageWithSigners,
} from "@solana/kit";

test("it transfers SOL from one wallet to another", async () => {
	// Given a payer with 2 SOL and a recipient with 0 SOL.
	const svm = new LiteSVM();
	const payer = await generateKeyPairSigner();
	const recipient = await generateKeyPairSigner();
	svm.airdrop(payer.address, lamports(2_000_000_000n));

	// When we send 1 SOL from the payer to the recipient.
	const instruction = getTransferSolInstruction({
		source: payer,
		destination: recipient.address,
		amount: lamports(1_000_000_000n),
	});
	const transaction = await pipe(
		createTransactionMessage({ version: 0 }),
		(tx) => setTransactionMessageFeePayerSigner(payer, tx),
		(tx) => svm.setTransactionMessageLifetimeUsingLatestBlockhash(tx),
		(tx) => appendTransactionMessageInstruction(instruction, tx),
		(tx) => signTransactionMessageWithSigners(tx),
	);

	const result = svm.sendTransaction(transaction);
	if (result instanceof FailedTransactionMetadata) {
		throw new Error(`Transaction failed: ${result.err()}`);
	}

	// Then we expect the accounts to have the correct balances.
  const payerBalance = svm.getBalance(payer.address);

  assert.strictEqual(
		svm.getBalance(recipient.address),
    lamports(1_000_000_000n),
  );
  assert(payerBalance !== null);
  assert(payerBalance < lamports(1_000_000_000n));
});

Note: by default the LiteSVM instance includes some core programs such as the System Program and SPL Token.

Installation

yarn add litesvm

Contributing

Make sure you have Yarn and the Rust toolchain installed.

Then run yarn to install deps, run yarn build to build the binary and yarn test to run the tests.