token/clients/js/test/_setup.ts

import {
  Address,
  Commitment,
  CompilableTransactionMessage,
  Rpc,
  RpcSubscriptions,
  SolanaRpcApi,
  SolanaRpcSubscriptionsApi,
  TransactionMessageWithBlockhashLifetime,
  TransactionSigner,
  airdropFactory,
  appendTransactionMessageInstructions,
  createSolanaRpc,
  createSolanaRpcSubscriptions,
  createTransactionMessage,
  generateKeyPairSigner,
  getSignatureFromTransaction,
  lamports,
  pipe,
  sendAndConfirmTransactionFactory,
  setTransactionMessageFeePayerSigner,
  setTransactionMessageLifetimeUsingBlockhash,
  signTransactionMessageWithSigners,
} from '@solana/web3.js';
import {
  TOKEN_PROGRAM_ADDRESS,
  getInitializeMintInstruction,
  getMintSize,
} from '../src/index.js';
import { getCreateAccountInstruction } from '@solana-program/system';

type Client = {
  rpc: Rpc<SolanaRpcApi>;
  rpcSubscriptions: RpcSubscriptions<SolanaRpcSubscriptionsApi>;
};

export const createDefaultSolanaClient = (): Client => {
  const rpc = createSolanaRpc('http://127.0.0.1:8899');
  const rpcSubscriptions = createSolanaRpcSubscriptions('ws://127.0.0.1:8900');
  return { rpc, rpcSubscriptions };
};

export const generateKeyPairSignerWithSol = async (
  client: Client,
  putativeLamports: bigint = 1_000_000_000n
) => {
  const signer = await generateKeyPairSigner();
  await airdropFactory(client)({
    recipientAddress: signer.address,
    lamports: lamports(putativeLamports),
    commitment: 'confirmed',
  });
  return signer;
};

export const createDefaultTransaction = async (
  client: Client,
  feePayer: TransactionSigner
) => {
  const { value: latestBlockhash } = await client.rpc
    .getLatestBlockhash()
    .send();
  return pipe(
    createTransactionMessage({ version: 0 }),
    (tx) => setTransactionMessageFeePayerSigner(feePayer, tx),
    (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx)
  );
};

export const signAndSendTransaction = async (
  client: Client,
  transactionMessage: CompilableTransactionMessage &
    TransactionMessageWithBlockhashLifetime,
  commitment: Commitment = 'confirmed'
) => {
  const signedTransaction =
    await signTransactionMessageWithSigners(transactionMessage);
  const signature = getSignatureFromTransaction(signedTransaction);
  await sendAndConfirmTransactionFactory(client)(signedTransaction, {
    commitment,
  });
  return signature;
};

export const getBalance = async (client: Client, address: Address) =>
  (await client.rpc.getBalance(address, { commitment: 'confirmed' }).send())
    .value;

export const createMint = async (
  client: Client,
  authority: TransactionSigner
): Promise<Address> => {
  const space = BigInt(getMintSize());
  const [transactionMessage, rent, mint] = await Promise.all([
    createDefaultTransaction(client, authority),
    client.rpc.getMinimumBalanceForRentExemption(space).send(),
    generateKeyPairSigner(),
  ]);
  const instructions = [
    getCreateAccountInstruction({
      payer: authority,
      newAccount: mint,
      lamports: rent,
      space,
      programAddress: TOKEN_PROGRAM_ADDRESS,
    }),
    getInitializeMintInstruction({
      mint: mint.address,
      decimals: 2,
      mintAuthority: authority.address,
    }),
  ];
  await pipe(
    transactionMessage,
    (tx) => appendTransactionMessageInstructions(instructions, tx),
    (tx) => signAndSendTransaction(client, tx)
  );

  return mint.address;
};