cargo add --dev litesvm

cargo add --dev solana-sdk

mkdir tests

use litesvm::LiteSVM;
use solana_sdk::signature::{Keypair, Signer};

#[test]
fn create_account() {
    // Create the test environment
    let mut svm = LiteSVM::new();

    // Create a test account
    let user = Keypair::new();

    // Fund the account with SOL
    svm.airdrop(&user.pubkey(), 1_000_000_000).unwrap();

    // Check the balance
    let balance = svm.get_balance(&user.pubkey()).unwrap();
    assert_eq!(balance, 1_000_000_000);

    println!("Account funded with {} SOL", balance as f64 / 1e9);
}

cargo test create_account -- --show-output

running 1 test
test create_account ... ok

successes:

---- create_account stdout ----
Account funded with 1 SOL

successes:
    create_account

use litesvm::LiteSVM;
use solana_sdk::{
    signature::{Keypair, Signer},
    system_instruction,
    transaction::Transaction,
};

#[test]
fn test_transfer() {
    let mut svm = LiteSVM::new();

    // Create two accounts
    let alice = Keypair::new();
    let bob = Keypair::new();

    // Fund Alice
    svm.airdrop(&alice.pubkey(), 2_000_000_000).unwrap();

    // Create transfer instruction
    let transfer = system_instruction::transfer(
        &alice.pubkey(),
        &bob.pubkey(),
        1_000_000_000, // 1 SOL
    );

    // Build and sign transaction
    let tx = Transaction::new_signed_with_payer(
        &[transfer],
        Some(&alice.pubkey()),
        &[&alice],
        svm.latest_blockhash(),
    );

    // Send it (execution happens immediately)
    svm.send_transaction(tx).unwrap();

    // Check new balances
    assert_eq!(svm.get_balance(&bob.pubkey()).unwrap(), 1_000_000_000);
    assert!(svm.get_balance(&alice.pubkey()).unwrap() < 1_000_000_000);

    println!("Transfer successful!");
}

cargo test -- --show-output

running 1 test
test create_account ... ok

successes:

---- create_account stdout ----
Account funded with 1 SOL

successes:
    create_account

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.04s

     Running tests/test_transfer.rs (target/debug/deps/test_transfer-f174954e7483f36b)

running 1 test
test test_transfer ... ok

successes:

---- test_transfer stdout ----
Transfer successful!

successes:
    test_transfer

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.04s