This is a typescript test for the Anchor program demonstrating a way how to return rent to the original payer on Solana

rent_return.ts

import * as anchor from "@coral-xyz/anchor";
import { Program } from "@coral-xyz/anchor";
import { RentReturn } from "../target/types/rent_return";
import { expect } from "chai";

const { SystemProgram, PublicKey } = anchor.web3;

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

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

  it("Rent is returned", async () => {
    const myAccount = PublicKey.findProgramAddressSync([Buffer.from("acc")], program.programId)[0];
    const startBalance = await provider.connection.getBalance(provider.wallet.publicKey);
    // Create account
    const tx = await program.methods.initialize().accounts({
      acc: myAccount,
      feePayer: provider.wallet.publicKey,
      systemProgram: SystemProgram.programId,
    }).rpc();
    console.log("Account creation transaction signature: ", tx);
    const accountCreationFee = startBalance - await provider.connection.getBalance(provider.wallet.publicKey);
    console.log("Paid for the account creation: ", accountCreationFee);

    // Close account
    const tx2 = await program.methods.close().accounts({
      acc: myAccount,
      destination: provider.wallet.publicKey,
    }).rpc();
    console.log("Account close transaction signature: ", tx2);
    const totalPaid = startBalance - await provider.connection.getBalance(provider.wallet.publicKey)
    console.log("Total fees  paid:", totalPaid);
    expect(totalPaid).to.be.lessThan(accountCreationFee);
  });
});