Account Management
Methods for managing accounts, balances, and rent
airdrop
pub fn airdrop(&mut self, pubkey: &Pubkey, lamports: u64) -> TransactionResult
Where TransactionResult
is Result<TransactionMetadata, FailedTransactionMetadata>
.
Fund an account with lamports. Returns transaction metadata on success.
let keypair = Keypair::new();
// Option 1: Ignore result if you don't care about tx details
svm.airdrop(&keypair.pubkey(), 10_000_000_000).unwrap();
// Option 2: Check transaction metadata
match svm.airdrop(&keypair.pubkey(), 10_000_000_000) {
Ok(meta) => {
println!("Airdrop successful");
println!("Compute units: {}", meta.compute_units_consumed);
}
Err(e) => {
println!("Airdrop failed: {:?}", e.err);
}
}
get_account
pub fn get_account(&self, pubkey: &Pubkey) -> Option<Account>
Retrieve account data.
let account = svm.get_account(&pubkey)?;
println!("Lamports: {}", account.lamports);
println!("Owner: {}", account.owner);
println!("Data length: {}", account.data.len());
set_account
pub fn set_account(&mut self, pubkey: Pubkey, account: Account) -> Result<(), LiteSVMError>
Directly set account state.
use solana_sdk::account::Account;
svm.set_account(pubkey, Account {
lamports: 1_000_000,
data: vec![0; 100],
owner: program_id,
executable: false,
rent_epoch: 0,
}).unwrap();
get_balance
pub fn get_balance(&self, pubkey: &Pubkey) -> Option<u64>
Get account lamport balance. Returns None
if account doesn't exist.
// Check if account exists and get balance
if let Some(balance) = svm.get_balance(&pubkey) {
println!("Balance: {} lamports", balance);
} else {
println!("Account doesn't exist");
}
// Or use unwrap_or for default
let balance = svm.get_balance(&pubkey).unwrap_or(0);
println!("Balance: {} lamports", balance);
minimum_balance_for_rent_exemption
pub fn minimum_balance_for_rent_exemption(&self, data_len: usize) -> u64
Calculate minimum lamports needed for rent exemption.
let data_len = 100;
let min_balance = svm.minimum_balance_for_rent_exemption(data_len);
svm.set_account(pubkey, Account {
lamports: min_balance,
data: vec![0; data_len],
owner: program_id,
executable: false,
rent_epoch: 0,
}).unwrap();
Performance Tips
Batch Account Creation
// Slow - individual operations
for i in 0..100 {
let account = Keypair::new();
svm.airdrop(&account.pubkey(), 1_000_000_000).unwrap();
}
// Fast - batch with set_account
let accounts: Vec<_> = (0..100)
.map(|_| {
let keypair = Keypair::new();
svm.set_account(keypair.pubkey(), Account {
lamports: 1_000_000_000,
data: vec![],
owner: solana_sdk::system_program::id(),
executable: false,
rent_epoch: 0,
}).unwrap();
keypair
})
.collect();
Account State Inspection
// Before transaction
let before = svm.get_account(&pubkey).unwrap();
// Execute
svm.send_transaction(tx).unwrap();
// After transaction
let after = svm.get_account(&pubkey).unwrap();
// Compare
assert_ne!(before.lamports, after.lamports);
assert_ne!(before.data, after.data);