solana-program-examples/basics/counter/seahorse/tests/counter_seahorse.ts

import * as anchor from "@project-serum/anchor";
import { Program } from "@project-serum/anchor";
import {
  Keypair,
  PublicKey,
  SystemProgram
} from '@solana/web3.js';
import { assert } from "chai";
import { CounterSeahorse } from "../target/types/counter_seahorse";

describe("counter_seahorse", () => {
  // Configure the client to use the local cluster.
  anchor.setProvider(anchor.AnchorProvider.env());

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

  it("Increment counter", async () => {
    const seed = 69;
    const counter = PublicKey.findProgramAddressSync(
      [Buffer.from([0x45])],
      program.programId
    )[0];

    // Initialize counter
    await program.methods
      .initializeCounter(seed)
      .accounts({
        payer: program.provider.publicKey,
      })
      .rpc();

    // Increment counter
    await program.methods
      .increment()
      .accounts({
        counter
      })
      .rpc();

    const count = (await program.account.counter.fetch(counter)).count.toNumber();
    assert(count === 1, "Expected count to be 1");
  });
});