solana-program-examples/basics/counter/anchor/tests/counter_anchor.ts

import * as anchor from '@coral-xyz/anchor';
import type { Program } from '@coral-xyz/anchor';
import { Keypair } from '@solana/web3.js';
import { assert } from 'chai';
import type { CounterAnchor } from '../target/types/counter_anchor';

describe('counter_anchor', () => {
  // Configure the client to use the local cluster.
  const provider = anchor.AnchorProvider.env();
  anchor.setProvider(provider);
  const payer = provider.wallet as anchor.Wallet;

  const program = anchor.workspace.CounterAnchor as Program<CounterAnchor>;

  // Generate a new keypair for the counter account
  const counterKeypair = new Keypair();

  it('Initialize Counter', async () => {
    await program.methods
      .initializeCounter()
      .accounts({
        counter: counterKeypair.publicKey,
        payer: payer.publicKey,
      })
      .signers([counterKeypair])
      .rpc();

    const currentCount = await program.account.counter.fetch(counterKeypair.publicKey);

    assert(currentCount.count.toNumber() === 0, 'Expected initialized count to be 0');
  });

  it('Increment Counter', async () => {
    await program.methods.increment().accounts({ counter: counterKeypair.publicKey }).rpc();

    const currentCount = await program.account.counter.fetch(counterKeypair.publicKey);

    assert(currentCount.count.toNumber() === 1, 'Expected  count to be 1');
  });

  it('Increment Counter Again', async () => {
    await program.methods.increment().accounts({ counter: counterKeypair.publicKey }).rpc();

    const currentCount = await program.account.counter.fetch(counterKeypair.publicKey);

    assert(currentCount.count.toNumber() === 2, 'Expected  count to be 2');
  });
});